#Influenza at human-animal interface - Summary & #risk #assessment (23 Jan. - 31 March 2026) (WHO, Apr. 29 '26): #H5N1, #H9N2, #H10N3, #H1N1v, #H3N2v cases reported

 

New human cases {2}: 

-- From 23 January to 31 March 2026, based on reporting date, detections of  influenza A(H5N1) in four humans, influenza A(H9N2) in five humans, influenza A(H10N3) in one human, an influenza A(H1N1) variant ((H1N1)v) virus in one human, an influenza A(H1N2)v virus in one human, and influenza A(H3N2)v virus in one human were reported officially. 

Circulation of influenza viruses with zoonotic potential in animals: 

-- High pathogenicity avian influenza (HPAI) events in poultry and non-poultry animal species continue to be reported to the World Organisation for Animal Health (WOAH).{3} 

-- The Food and Agriculture Organization of the United Nations (FAO) also provides a global update on avian influenza viruses with pandemic potential.{4} 

-- Additionally, low pathogenicity avian influenza viruses as well as swine influenza viruses continue to circulate in animal populations. 

Risk assessment {5}: 

-- Sustained human to human transmission has not been reported associated with the above-mentioned human infection events. 

-- Based on information available at the time of this risk assessment update, the overall public health risk from currently known influenza A viruses detected at the human-animal interface has not changed and remains low. 

-- The occurrence of sustained human-to-human transmission of these viruses is currently considered unlikely. 

-- Although human infections with viruses of animal origin are infrequent, they are not unexpected at the human-animal interface.  

Risk management: 

-- Candidate vaccine viruses (CVVs) for zoonotic influenza viruses for pandemic preparedness purposes were reviewed and updated at the February 2026 WHO consultation on influenza vaccine composition for use in the northern hemisphere 2026-2027 influenza season. 

-- A detailed summary of zoonotic influenza viruses characterized since September 2025 is published here and updated CVVs lists are published here.  

IHR compliance {6}: 

-- This includes any influenza A virus that has demonstrated the capacity to infect a human and its haemagglutinin (HA) gene (or protein) is not a mutated form of those, i.e. A(H1) or A(H3), circulating widely in the human population. 

-- Information from these notifications is critical to inform risk assessments for influenza at the human-animal interface.  

Avian influenza viruses in humans -  Current situation:  

-- Since the last risk assessment of 22 January 2026, four laboratory-confirmed human cases of A(H5N1) infection were detected in Bangladesh (one case) and Cambodia (three cases).  

-- A(H5N1), Bangladesh  

- On 9 February 2026, the National International Health Regulations Focal Point of Bangladesh notified WHO of a laboratory-confirmed human case of avian influenza A(H5) infection in a child from Chattogram Division. 

- The patient, with no known comorbidities, developed symptoms on 21 January 2026 and was admitted to hospital on 28 January.  

- A nasopharyngeal swab was collected on 29 January as part of the Hospital-based Influenza Surveillance (HBIS) platform for influenza-like illness (ILI) and severe acute respiratory infection (SARI) sentinel surveillance in Bangladesh. 

- The patient was referred to a specialized private hospital and admitted to intensive care on 31 January. 

- The patient died on 1 February.  

- On 7 February, the Institute of Epidemiology, Disease Control and Research (IEDCR), serving as the National Influenza Centre (NIC), received and tested the sample, confirming influenza A(H5) by realtime reverse transcription polymerase chain reaction (RT-PCR) on the same day. 

- Virus characterization and whole genome sequencing was conducted at International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), which confirmed that the A(H5N1) virus belongs to clade 2.3.2.1a of highly pathogenic avian influenza A(H5N1) virus (Gs/GD lineage), similar to the clade of viruses circulating in local poultry since around 2011. 

- Genetic sequence data are available in GISAID (EPI_ISL_20367262; submission date 19 Feb 2026; Institute of Epidemiology, Disease Control & Research (IEDCR)). 

- The case had exposure to household poultry, with two ducks and one chicken reportedly dying shortly before the case’s illness onset. 

- Animal and environmental samples were collected and tested with RT-PCR and serology by the zoonotic investigation team of icddr,b. 

- Two samples from ducks in the community and two samples from chicken meat in the freezer of household tested positive for influenza A(H5). 

- Samples from symptomatic close human contacts tested negative for influenza.  

- This is the first confirmed human case of avian influenza A(H5) reported in Bangladesh in 2026. 

- In 2025, four human cases of avian influenza A(H5) were reported.  

- According to reports received by WOAH, various influenza A(H5) subtypes continue to be detected in wild and domestic birds in Africa, the Americas, Asia and Europe. 

- Infections in non-human mammals are also reported, including in marine and land mammals.{7} 

- A list of bird and mammalian species affected by HPAI A(H5) viruses is maintained by FAO.{8}   

-- A(H5N1), Cambodia 

- Between 15 February and 31 March 2026, Cambodia notified WHO of three laboratory-confirmed cases of A(H5N1) virus infection. 

(...)

- All cases above had exposure to sick or dead backyard poultry. 

- The first case was detected through SARI surveillance. 

- The other two cases were detected following the detection of A(H5N1) in sick and dead poultry which initiated deployment of rapid response teams from the public health sector and active case finding. 

- The last case was identified as having had exposure to sick and dead poultry, sampled and then developed ILI symptoms. 

- Three human infections with A(H5N1) viruses have been confirmed in Cambodia in 2026 and none have been fatal. 

- Influenza A(H5N1) viruses continue to be detected in domestic birds in Cambodia in 2026, including in areas where human cases have been detected.{9} 

- Where the information is available, the genetic sequence data from the viruses from the human cases closely matches that from recent local animal viruses and are identified as clade 2.3.2.1e viruses. 

- From the information available thus far on these recent human cases, there is no indication of human-to-human transmission of the A(H5N1) viruses.   

-- A(H9N2), China  

- Between 9 February and 20 March 2026, China notified WHO of four laboratory-confirmed cases of A(H9N2) virus infection. 

(...)

-- A(H9N2), Italy, ex-Senegal {10} 

- On 21 March 2026, Italy notified WHO of the detection of A(H9N2) virus in an adult male. 

- The case had travelled to Senegal for more than six months and returned to Italy in mid-March 2026. 

- Upon arrival in Italy, the case sought medical care, presenting with fever and persistent cough that had been present since mid-January. 

- Laboratory investigations conducted on a bronchoalveolar lavage specimen on 16 March showed a positive Mycobacterium tuberculosis result, as well as detection of an un-subtypeable influenza A virus. 

- The case was admitted to an isolation room under airborne precautions in a negative-pressure room and received antitubercular and antiviral treatment. 

- As of 24 March, the patient was clinically stable and improving.  

- On 20 March 2026, the regional reference laboratory confirmed the A(H9) subtype, and on 21 March, influenza A(H9N2) was confirmed by next-generation sequencing. 

- Initial genetic findings suggest the infection was likely acquired from an avian source linked to Senegal. 

- Additional samples have been sent to Italy’s National Influenza Center, where further characterization confirmed virus subtype Influenza A(H9N2), with close genetic similarity to strains previously identified in poultry in Senegal. 

- No direct exposure to animals, wildlife or rural environments was identified. 

- There was also no reported contact with symptomatic or confirmed human cases. 

- Further epidemiological investigations on the source of exposure are ongoing. 

- Contacts identified in Senegal were asymptomatic. 

- All identified and traced contacts in Italy have tested negative for influenza and completed the period of active monitoring for the onset of symptoms and the quarantine required by national guidelines. 

- Human infections with influenza A(H9) viruses have been reported from countries in Africa and Asia, where these viruses are also detected in poultry. 

- This is the first imported human case of avian influenza A(H9N2) reported in the European Region. 

-- Risk Assessment for avian influenza A(H9N2):  

- 1. What is the global public health risk of additional human cases of infection with avian influenza A(H9N2) viruses?  

Most human cases follow exposure to the A(H9N2) virus through contact with infected poultry or contaminated environments. 

Most human infections of A(H9N2) to date have resulted in mild clinical illness. 

Since the virus is endemic in poultry in multiple countries in Africa and Asia, additional human cases associated with exposure to infected poultry or contaminated environments are expected but remain unusual. 

The impact to public health if additional sporadic cases are detected is minimal. 

The overall global public health risk is low.  

- 2. What is the likelihood of sustained human-to-human transmission of avian influenza A(H9N2) viruses related to these events?  

At the present time, no sustained human-to-human transmission has been identified associated with the recently reported human infections with A(H9N2) viruses. 

Current evidence suggests that A(H9N2) viruses from these cases did not acquire the ability of sustained transmission among humans, therefore sustained human-to-human transmission is thus currently considered unlikely.  

- 3. What is the likelihood of international spread of avian influenza A(H9N2) virus by travellers?  

Should infected individuals from affected areas travel internationally, their infection may be detected in another country during travel or after arrival, such as in the case reported by Italy. 

If this were to occur, further community level spread is considered unlikely as current evidence suggests the A(H9N2) virus subtype has not acquired the ability to transmit easily among humans.  

-- A(H10N3), China  

- On 9 February 2026, China notified WHO of one laboratory-confirmed case of human infection with an avian influenza A(H10N3) virus in a 34-year-old man from Guangdong province who developed symptoms on 29 December 2025. 

- On 1 January 2026, he was admitted to hospital and diagnosed with severe pneumonia, severe acute respiratory distress syndrome (ARDS) and sepsis. 

- Oseltamivir treatment was initiated on 3 January. 

- The patient's condition was stable at the time of reporting. 

- On 12 January, the sample was sent to the provincial laboratory for testing. 

- The result was positive for A(H10N3). On 14 January, the National Influenza Center confirmed the positive result.    

- The patient works near two establishments that keep live poultry on the premises and chickens are present at the household. 

- Environmental samples collected from sites related to likely poultry exposure, including the patient's home, the workplace and a nearby poultry market tested negative for A(H10N3) influenza virus. 

- No further cases were detected among contacts of these cases.   

- A total of 98 close contacts of the patient were traced.  

- Since 2021, a total of seven cases of human avian influenza A(H10N3) virus infection have been reported globally and all were from China.   

-- Risk Assessment for avian influenza A(H10N3):   

- 1. What is the global public health risk of additional human cases of infection with avian influenza  A(H10N3) viruses?   

Human infections with avian influenza A(H10) viruses have been detected and reported previously.   

The circulation and epidemiology of these viruses in birds have been previously reported.{12} 

Avian influenza A(H10N3) viruses with different genetic characteristics have been detected previously in wild birds since the 1970s and more recently spilled over to poultry in some countries. 

As long as the virus continues to circulate in birds, further human cases can be expected but remain unusual. 

The impact to public health if additional sporadic cases are detected is minimal. 

The overall global public health risk of additional sporadic human cases is low.    

- 2. What is the likelihood of sustained human-to-human transmission of avian influenza A(H10N3)   viruses?   

No sustained human-to-human transmission has been identified associated with the event described above or past events with human cases of influenza A(H10N3) viruses. 

Current epidemiologic and virologic evidence suggests that contemporary influenza A(H10N3) viruses assessed by the Global Influenza Surveillance and response System (GISRS) have not acquired the ability of sustained transmission among humans, therefore sustained human-to-human transmission is thus currently considered unlikely.    

- 3. What is the likelihood of international spread of avian influenza A(H10N3) virus by travellers?   

Should infected individuals from affected areas travel internationally, their infection may be   detected in another country during travel or after arrival. 

If this were to occur, further community   level spread is considered unlikely based on current limited evidence.  

Swine influenza viruses in humans  

-- Influenza A(H1N1)v, China  

- On 20 March 2026, China notified WHO of a laboratory-confirmed case of A(H1N1)v influenza virus infection in a child from Yunnan province. 

- The patient had onset of illness on 30 January 2026, was hospitalized on 2 February with pneumonia, and recovered in a few days. 

- The patient had reported exposure to domestic pigs prior to illness onset.  

-- Influenza A(H1N2)v, China 

- On 3 February 2026, China notified WHO of a laboratory-confirmed case of A(H1N2)v influenza virus infection in a child from Yunnan province. 

- The patient had onset of mild illness on 20 January 2026, and the infection was laboratory-confirmed on 2 February 2026. 

- The patient had reported exposure to domestic pigs prior to illness onset. This case and the one above are not epidemiologically linked.  

-- Influenza A(H3N2)v, Brazil 

- On 26 January 2026, Brazil notified WHO of a laboratory-confirmed case of A(H3N2)v influenza virus infection. 

- On 1 September 2025, a male child residing in the state of Mato Grosso do Sul presented with ILI symptoms and was taken to a health unit on 2 September. 

- The patient had no reported comorbidities or recent travel history and reported being vaccinated against seasonal influenza in the last campaign. 

- On 9 September, a respiratory sample was collected at the health unit, which is a sentinel unit for ILI. 

- On 12 September, the Central Public Health Laboratory of Mato Grosso do Sul (Lacen/MS) reported that the RT-qPCR test for influenza A virus subtyping amplified the influenza A marker along with the H3 marker, indicating a swine-origin variant of the influenza H3 virus. 

- The sample was sent to the National Influenza Center (NIC) of the Adolfo Lutz Institute, where the A(H3N2)v was confirmed by molecular tests and genomic sequencing. 

- The sequences were entered into GISAID on 1 October. 

- The sample was also shared with the WHO Collaborating Centre at the US Centers for Disease Control and Prevention (CDC), where it was genomically and antigenically characterized. 

- An epidemiological investigation was conducted, which identified the case as a student at an agricultural school where pigs and laying hens are raised, although the institution's coordinators reported that the students had not had direct contact with pigs recently. 

- It was reported that the case had contact with classmates who presented ILI symptoms during this period. 

- All household contacts were vaccinated against seasonal influenza in the 2025 season, except for the patient's mother. 

- To date, no other human cases of infection with the A(H3N2)v virus have been detected in association with this case. 

-- Risk Assessment:   

- 1. What is the public health risk of additional human cases of infection with swine influenza viruses?   

Swine influenza viruses circulate in swine populations in many regions of the world. 

Depending on geographic location, the genetic characteristics of these viruses differ. 

Most human cases are exposed to swine influenza viruses through contact with infected animals or contaminated environments. 

Human infection tends to result in mild clinical illness in most cases. 

Since these viruses continue to be detected in swine populations, further human cases are expected. 

The impact to public health if additional sporadic cases are detected is minimal. 

The overall risk of additional sporadic human cases is low.   

- 2. What is the likelihood of sustained human-to-human transmission of swine influenza viruses?    

No sustained human-to-human transmission was identified associated with the events described above. 

Current evidence suggests that contemporary swine influenza viruses have not acquired the ability of sustained transmission among humans, therefore sustained human-to-human transmission is thus currently considered unlikely.  

- 3. What is the likelihood of international spread of swine influenza viruses by travelers?    

Should infected individuals from affected areas travel internationally, their infection may be detected in another country during travel or after arrival. 

If this were to occur, further community level spread is considered unlikely as current evidence suggests that these viruses have not acquired the ability to transmit easily among humans.  

For more information on zoonotic influenza viruses, see the report from the WHO Consultation on the Composition of Influenza Virus Vaccines for Use in the 2026-2027 Northern Hemisphere Influenza Season that was held on 23-26 February 2026 at this link.  

Overall risk management recommendations: 

Surveillance and investigations 

• Due to the constantly evolving nature of influenza viruses, WHO continues to stress the importance of global strategic surveillance in animals and humans to detect virologic, epidemiologic and clinical changes associated with circulating influenza viruses that may affect human (or animal) health. 

- Continued vigilance is needed within affected and neighbouring areas to detect infections in animals and humans. 

- Close collaboration with the animal health and environment sectors is essential to understand the extent of the risk of human exposure and to prevent and control the spread of animal influenza. 

- WHO has published guidance on surveillance for human infections with avian influenza A(H5) viruses. 

• As the extent of influenza virus circulation in animals is not clear, epidemiologic and virologic surveillance and the follow-up of suspected human cases should continue systematically. 

- Guidance on investigation of non-seasonal influenza and other emerging acute respiratory diseases has been published on the WHO website. 

• Countries should: 

- increase avian influenza surveillance in domestic and wild birds, 

- enhance surveillance for early detection in cattle populations in countries where HPAI is known to be circulating, include HPAI as a differential diagnosis in non-avian species, including cattle and other livestock populations, with high risk of exposure to HPAI viruses; 

- monitor and investigate cases in non-avian species, including livestock, report cases of HPAI in all animal species, including unusual hosts, to WOAH and other international organizations, 

- share genetic sequences of avian influenza viruses in publicly available databases, 

- implement preventive and early response measures to break the HPAI transmission cycle among animals through movement restrictions of infected livestock holdings and strict biosecurity measures in all holdings, 

- employ good production and hygiene practices when handing animal products, and 

- protect persons in contact with suspected/infected animals.{11} 

- More guidance can be found from WOAH and FAO. 

• When there has been human exposure to a known outbreak of an influenza A virus in domestic poultry, wild birds or other animals – or when there has been an identified human case of infection with such a virus – enhanced surveillance in potentially exposed human populations becomes necessary. 

- Enhanced surveillance should consider the health care seeking behaviour of the population, and could include a range of active and passive health care and/or communitybased approaches, including: 

* enhanced surveillance in local influenza-like illness (ILI)/SARI systems, 

* active screening in hospitals and of groups that may be at higher occupational risk of exposure, and 

* inclusion of other sources such as traditional healers, private practitioners and private diagnostic laboratories. 

• Vigilance for the emergence of novel influenza viruses with pandemic potential should be maintained at all times including during a non-influenza emergency. 

- In the context of the cocirculation of SARS-CoV-2 and influenza viruses, WHO has updated and published practical guidance for integrated surveillance. 

Notifying WHO 

• All human infections caused by a new subtype of influenza virus are notifiable under the International Health Regulations (IHR, 2005).{12,13} 

- State Parties to the IHR (2005) are required to immediately notify WHO of any laboratory-confirmed{14} case of a recent human infection caused by an influenza A virus with the potential to cause a pandemic{15}. 

- Evidence of illness is not required for this report. Evidence of illness is not required for this report. 

• WHO published the case definition for human infections with avian influenza A(H5) virus requiring notification under IHR (2005): https://www.who.int/teams/global-influenzaprogramme/avian-influenza/case-definitions. 

Virus sharing and risk assessment 

• It is critical that these influenza viruses from animals or from humans are fully characterized in appropriate animal or human health influenza reference laboratories. 

- Under WHO’s Pandemic Influenza Preparedness (PIP) Framework, Member States are expected to share influenza viruses with pandemic potential on a timely basis16 with a WHO Collaborating Centre for influenza of GISRS. 

- The viruses are used by the public health laboratories to assess the risk of pandemic influenza and to develop candidate vaccine viruses.  

• The Tool for Influenza Pandemic Risk Assessment (TIPRA) provides an in-depth assessment of risk associated with some zoonotic influenza viruses – notably the likelihood of the virus gaining human-to-human transmissibility, and the impact should the virus gain such transmissibility. 

- TIPRA maps relative risk amongst viruses assessed using multiple risk elements. 

- The results of TIPRA complement those of the risk assessment provided here, and those of prior TIPRA risk assessments are published at  http://www.who.int/teams/global-influenza-programme/avianinfluenza/tool-for-influenza-pandemic-risk-assessment-(tipra).  

Risk reduction 

• Given the observed extent and frequency of avian influenza in poultry, wild birds and some wild and domestic mammals, the public should avoid contact with animals that are sick or dead from unknown causes, including wild animals, and should report dead birds and mammals or request their removal by contacting local wildlife or veterinary authorities.  

• Eggs, poultry meat and other poultry food products should be properly cooked and properly handled during food preparation. Due to the potential health risks to consumers, raw milk should be avoided. WHO advises consuming pasteurized milk. If pasteurized milk isn’t available, heating raw milk until it boils makes it safer for consumption. 

• WHO has published practical interim guidance to reduce the risk of infection in people exposed to avian influenza viruses. 

Trade and travellers 

• WHO advises that travellers to countries with known outbreaks of animal influenza should avoid farms, contact with animals in live animal markets, entering areas where animals may be slaughtered, or contact with any surfaces that appear to be contaminated with animal excreta. Travelers should also wash their hands often with soap and water. All individuals should follow good food safety and hygiene practices.  

• WHO does not advise special traveller screening at points of entry or restrictions with regards to the current situation of influenza viruses at the human-animal interface. 

- For recommendations on safe trade in animals and related products from countries affected by these influenza viruses, refer to WOAH guidance.  

Links:  

- WHO Human-Animal Interface web page https://www.who.int/teams/global-influenza-programme/avian-influenza 

- WHO Influenza (Avian and other zoonotic) fact sheet https://www.who.int/news-room/fact-sheets/detail/influenza-(avian-and-other-zoonotic) 

- WHO Protocol to investigate non-seasonal influenza and other emerging acute respiratory diseases https://www.who.int/publications/i/item/WHO-WHE-IHM-GIP-2018.2 

- WHO Public health resource pack for countries experiencing outbreaks of influenza in animals:  https://www.who.int/publications/i/item/9789240076884 

- Cumulative Number of Confirmed Human Cases of Avian Influenza A(H5N1) Reported to WHO  https://www.who.int/teams/global-influenza-programme/avian-influenza/avian-a-h5n1-virus 

- Avian Influenza A(H7N9) Information https://www.who.int/teams/global-influenza-programme/avian-influenza/avian-influenza-a-(h7n9)virus 

- World Organisation of Animal Health (WOAH) web page: Avian Influenza  https://www.woah.org/en/home/ 

- Food and Agriculture Organization of the United Nations (FAO) webpage: Avian Influenza https://www.fao.org/animal-health/avian-flu-qa/en/ 

- WOAH/FAO Network of Expertise on Animal Influenza (OFFLU) http://www.offlu.org/ 

___

{1} This summary and assessment covers information confirmed during this period and may include information received outside of this period. 

{2} For epidemiological and virological features of human infections with animal influenza viruses not reported in this assessment, see the reports on human cases of influenza at the human-animal interface published in the Weekly Epidemiological Record here.  

{3} World Organisation for Animal Health (WOAH). Avian influenza. Global situation. Available at: https://www.woah.org/en/disease/avian-influenza/#ui-id-2. 

{4} Food and Agriculture Organization of the United Nations (FAO). Global Avian Influenza Viruses with Zoonotic Potential situation update. Available at: https://www.fao.org/animal-health/situation-updates/global-aiv-withzoonotic-potential. 

{5} World Health Organization (2012). Rapid risk assessment of acute public health events. World Health Organization. Available at: https://iris.who.int/handle/10665/70810. 

{6} World Health Organization. Case definitions for the four diseases requiring notification in all circumstances under the International Health Regulations (2005). Available at: https://www.who.int/publications/m/item/case-definitions-for-the-four-diseases-requiring-notification-towho-in-all-circumstances-under-the-ihr-(2005).  

{7} World Organisation for Animal Health (WOAH). Avian influenza. Global situation. Available at: https://www.woah.org/en/disease/avian-influenza/#ui-id-2. 

{8} Food and Agriculture Organization of the United Nations. Global Avian Influenza Viruses with Zoonotic Potential situation update. Available at: https://www.fao.org/animal-health/situation-updates/global-aiv-withzoonotic-potential/bird-species-affected-by-h5nx-hpai/en. 

{9} World Organisation for Animal Health. WAHIS. https://wahis.woah.org/#/in-review/7409. 

{10} World Health Organization. World Health Organization (10 April 2026). Disease Outbreak News: Avian Influenza A(H9N2) in Italy (https://www/who.int/emergencies/disease-outbreak-news/item/2026-DON597). 

{11} World Organisation for Animal Health. Statement on High Pathogenicity Avian Influenza in Cattle, 6 December 2024 (https://www.woah.org/en/high-pathogenicity-avian-influenza-hpai-in-cattle/). 

{12} World Health Organization. International Health Regulations (2005), as amended through resolutions WHA67.13 (2014), WHA75.12 (2022), and WHA77.17 (2024) (https://apps.who.int/gb/bd/pdf_files/IHR_20142022-2024-en.pdf). 

{13} World Health Organization. Case definitions for the four diseases requiring notification in all circumstances under the International Health Regulations (2005) (https://www.who.int/publications/m/item/casedefinitions-for-the-four-diseases-requiring-notification-to-who-in-all-circumstances-under-the-ihr-(2005)). 

{14} World Health Organization. Manual for the laboratory diagnosis and virological surveillance of influenza (2011) (https://apps.who.int/iris/handle/10665/44518). 

{15} World Health Organization. Pandemic influenza preparedness framework for the sharing of influenza viruses and access to vaccines and other benefits, 2nd edition (https://iris.who.int/handle/10665/341850). 

{16} World Health Organization. Operational guidance on sharing influenza viruses with human pandemic potential (IVPP) under the Pandemic Influenza Preparedness (PIP) Framework (2017) (https://apps.who.int/iris/handle/10665/259402). 

Source: 

Link: https://www.who.int/publications/m/item/influenza-at-the-human-animal-interface-summary-and-assessment--31-march-2026

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Retrospective #Phylogenetic Analysis of #Mayaro Virus, French #Guiana, 1996–2024

 

Abstract

We conducted a retrospective phylogenetic analysis of Mayaro virus (MAYV) detected in French Guiana during 1996–2024. Analysis revealed circulation of MAYV genotype D sublineage 2 and suggested introduction from Brazil and spread to Haiti and Venezuela. Phylogenetic findings support endemic circulation and reinforce the need for MAYV surveillance in the region.

Source: 

Link: https://wwwnc.cdc.gov/eid/article/32/5/25-1435_article

____

#Chikungunya fever: #Brazil is intensifying its response to address health emergency in Dourados (MoH, April 4 '26)

 

{Edited}

The Brazilian government has intensified its response to the emergency situation in Dourados (MS), given the increase in cases of chikungunya, with the mobilization of an interministerial task force that integrates actions in health, assistance, civil defense, and logistical support in the territory. The emergency affects the population of the municipality, with a greater impact on indigenous communities.

As a reinforcement to the response already underway, the Federal Government has guaranteed more than R$ 3.1 million in emergency resources for the municipality. 

Of this total, R$ 1.3 million , authorized by the Ministry of Integration and Regional Development (MIDR) in a decree published this Thursday (2), will be allocated to relief and humanitarian assistance actions, such as direct support to the population and local response structures. 

Also this Thursday, the National Secretariat for Civil Protection and Defense approved a work plan worth R$ 974,100 for restoration actions, including urban cleaning, waste removal and disposal in a licensed sanitary landfill, with resources to be transferred directly to the municipality.

The Ministry of Health has already transferred R$ 855,300 to the municipality to cover the costs of surveillance, assistance, and control actions related to chikungunya in the region.

The federal response has been underway since mid-March, coordinated by the Ministry of Health, which mobilized the National Health System (SUS) Task Force , reinforced healthcare teams, and intensified vector surveillance and control actions across the territory. 

The operation includes actively searching for cases, conducting home visits, eliminating [mosquitoes] breeding sites, and expanding services to the population, with special attention to the most vulnerable areas, including indigenous territories.

The National Health System Task Force has 40 mobilized professionals , with 26 currently working directly, and has already carried out 1,288 clinical consultations , 81 transfers for medium and high complexity care, and 225 home visits . 

The teams operate both in indigenous territories and in the municipalities of Dourados and Itaporã, supporting local management, together with the Mato Grosso do Sul State Health Secretariat, reorganizing care flows, expanding active case finding, and guaranteeing assistance, health education, and psychosocial care.

Fiocruz mobilized the shipment of pain medication, reinforcing its ability to meet local demand due to the epidemic.

To expand response capacity, the Ministry of Health authorized the emergency hiring of 50 Endemic Disease Control Agents (ACEs). Of these, 20 have already been trained and will enter the field this Friday (3), while another 30 will begin training to work from Monday (6).

In the field of vector control, actions were intensified with the mobilization of approximately 95 professionals , including Community Health Agents and Indigenous Sanitation Agents (AISAN). Between March 9 and 16, 4,319 properties were inspected , of which 2,173 received treatment , identifying 1,004 breeding sites of the Aedes aegypti mosquito , mainly in water storage containers, solid waste, and tires.

Actions were also taken to control the spread of insecticide using ultra-low volume (ULV) methods, including three cycles of vehicle-mounted ULV application and backpack spraying in 43 high-traffic areas, such as schools and health units. The volunteer effort to remove breeding sites mobilized approximately 100 people and resulted in the collection of four dump truckloads of waste.

Vector control will be reinforced with support from the Ministry of Defense. Currently, 40 Brazilian Army soldiers and five vehicles are already in the area , expanding the operational capacity of the mosquito control efforts.

The Ministry of Health also sent 1,000 Larvicide Dissemination Stations (LDSs). Of the first 300 units, 150 have already been installed in priority neighborhoods, with expansion planned for other regions of the municipality.

Through Funai (National Indian Foundation), actions are also underway to provide direct support to indigenous communities in Dourados, focusing on food security and access to water. 

The distribution of 6,000 food baskets is planned , in three stages between April and June, in coordination with the Ministry of Social Development (MDS), the National Supply Company (Conab), the Special Secretariat for Indigenous Health (Sesai), and Civil Defense. The expansion of the water supply system in the Jaguapiru and Bororó villages has also been authorized to guarantee access to potable water and improve the sanitary conditions of the indigenous communities.

Epidemiological scenario

The most recent epidemiological surveillance data, referring to April 2nd, indicates that the region has registered 2,812 notifications of chikungunya, with 1,198 confirmed, 430 discarded, and 1,184 still under investigation. The highest concentration of cases is in indigenous villages, where 822 cases were confirmed—68.6% of the total confirmations in the region. 

So far, five deaths have been confirmed in Dourados, all among the indigenous population of the municipality.

To strengthen the coordination of actions, the Ministry of Health established a Situation Room in Brasília on March 25th, with permanent meetings to monitor the situation and integrate decisions between technical teams and managers.

Within the indigenous territory, the work is carried out in a coordinated manner between the Ministries of Health, Indigenous Peoples, Integration and Regional Development, Defense, Social Development, Funai (National Indian Foundation), and the Special Indigenous Health District of Mato Grosso do Sul (DSEI-MS), which has 210 Indigenous Health Agents (AIS) and 150 Indigenous Sanitation Agents (Aisan), in addition to logistical support with 91 pickup trucks, 6 vans, and 1 truck.

The actions also include training for health professionals in the municipal and indigenous networks, aligning clinical protocols for diagnosis and proper management of the disease, as well as health education activities in schools and communities. There are also plans to send prevention messages via WhatsApp to more than 234,000 residents , in Portuguese and with translation into indigenous languages.

The response also includes improving the quality of care, with the implementation of the national chikungunya protocol and training of teams for early identification of severe cases and appropriate clinical management.

Source: 

Link: https://www.gov.br/saude/pt-br/assuntos/noticias/2026/abril/governo-do-brasil-intensifica-resposta-integrada-e-mobiliza-forca-tarefa-para-enfrentar-emergencia-sanitaria-em-dourados-ms-2

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#Oropouche virus #outbreaks in northeast #Brazil between 2024–25 are characterized by sustained #transmission and spread to newly affected areas

 

Abstract

Oropouche virus (OROV) has recently expanded in Brazil, establishing transmission in non-endemic regions. This study aims to integrate epidemiological and molecular data to investigate OROV spread in Northeast (NE) Brazil between 2024 and 2025. OROV cases were analyzed regarding ecological risk factors and geographical clustering. Additionally, we sequenced 65 new OROV genomes from the Northeast states of Pernambuco, Paraíba, and Sergipe to infer the virus’s spatiotemporal dynamics in NE Brazil. A total of 2,806 confirmed cases were reported between March 2024 and April 2025, affecting 170 municipalities across eight out of nine NE states, with highly heterogeneous incidence. An ecological shift was observed, with OROV transmission moving from Atlantic Forest areas in 2024 to humid Caatinga zones in 2025. Phylogenetic reconstruction revealed multiple independent viral introductions in Northeast in 2024, including two in Pernambuco. The first, originating from the central Amazonas, became the main driver of local transmission and subsequently spread to Sergipe and Paraíba, causing outbreaks in 2024 and 2025, respectively. The second introduction remained restricted within Pernambuco. While several Northeast municipalities reported high OROV incidence, Jaqueira (Pernambuco) emerged as a key hub for regional viral spread. OROV showed sustained transmission in the region over a two-year period, characterized by marked spatiotemporal displacement consistent with short-lived, rapidly spreading outbreaks, followed by cryptic transmission and subsequent dissemination to new areas, ultimately driving renewed intense outbreaks.

Source: 

Link: https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0014171

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#Culicoides (Diptera: Ceratopogonidae) in Extra-Amazonian #Oropouche #Outbreak Areas of Minas Gerais, #Brazil: #Ecological Insights into Virus Transmission

 

Abstract

Oropouche fever (OF), caused by Oropouche virus (OROV), has expanded beyond its Amazonian range into Minas Gerais (MG), Brazil, raising concern about transmission in extra-Amazonian Atlantic Forest landscapes. Critical gaps persist regarding Culicoides vector communities, anthropophily, and climate-sensitive transmission risk in these newly affected regions. We conducted targeted entomological surveys outbreak-driven by human OF cases, standardized across five MG communities using CDC light traps and Protected Human Attraction (PHA) to characterize Culicoides composition. Females of Culicoides underwent RT-qPCR for OROV (n = 819) and physiological assessment (n = 312). We developed an entomological alert framework that integrates blood-fed abundance, minimum infection rate (MIR) upper confidence bounds, and environmental drivers (i.e., mean temperature, relative humidity and precipitation) via generalized additive mixed models, which explained 68% of the variability in Culicoides abundance and the alert index across communities. We collected 1171 Culicoides individuals representing five species (C. leopoldoi, C. paraensis, C. pusillus, C. foxi, and C. limai). C. leopoldoi (79.1%) and C. paraensis (20.3%) were the predominant species; notably, C. paraensis is recognized as the primary vector of OROV in the Americas. C. paraensis was documented for the first time in all five outbreak areas and dominated PHA captures (90%), suggesting anthropophily. Although no specimens tested OROV-positive (consistent with expected field infection rates of 0.01–1%), MIR upper bounds reached 132/1000 in low-sample settings and humidity and temperature strongly modulated abundance. This operational baseline and alert index transform virologically negative, sparse surveillance data into prioritized targets for intensified sampling and vector control during early, low-prevalence phases, when containment of OROV’s extra-Amazonian spread is still achievable.

Source: 

Link: https://www.mdpi.com/1999-4915/18/3/361

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#Brazil - #Influenza A #H5N1 viruses of high pathogenicity (Inf. with) (non-poultry including wild birds) (2017-) - Immediate notification

 

The Official Veterinary Service (OVS) of the state of Mato Grosso received a notification of a suspected case influenza A viruses of high pathogenicity in domestic birds from a multi-species backyard, on December 20, 2025. Official Laboratory (LFDA-SP) analysis confirmed the presence of the H5N1 virus, clade 2.3.4.4b. The premises have been placed under quarantine. Birds will be culled, and carcasses, products, and any potentially contaminated materials will be destroyed. The OVS is currently conducting an epidemiological investigation in the surrounding area.

Source: 

Link: https://wahis.woah.org/#/in-review/7147

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#Safety and immunogenicity of a live-attenuated #chikungunya virus #vaccine in #adolescents: final results from a ... phase 3 trial in endemic areas of #Brazil

 

Summary

Background

Chikungunya outbreaks have recurred in Brazil since 2014. Building on earlier 28-day post-vaccination data, we now report 12-month safety and immunogenicity results of the VLA1553 vaccine in Brazilian adolescents.

Methods

In this double-blind, randomised, placebo-controlled, phase 3 trial, generally healthy adolescents aged 12–17 years were recruited at ten sites across Brazil. Individuals were excluded for immune-mediated or chronic arthritis or arthralgia, who are are immunologically compromised, or any recent live vaccines. Random allocation via simple block randomisation in a 2:1 ratio was stratified by baseline IgG and IgM serostatus by ELISA to receive a single intramuscular dose of VLA1553 or placebo. Assessed in the per-protocol population 28 days after vaccination, the primary endpoint was the proportion of baseline seronegative participants with chikungunya virus neutralising antibody levels assessed by a serum dilution achieving a 50% plaque reduction in a micro plaque reduction neutralisation test with a titre of 150 or more, an accepted surrogate of protection. Safety was assessed in all vaccinated participants and covered by several secondary trial endpoints; immunogenicity formed a prespecified subset for analysis. The trial is registered with ClinicalTrials.gov (NCT04650399) and is complete.

Findings

Between Feb 14, 2022, and Feb 16, 2024, 754 participants were vaccinated (502 [67%] with VLA1553 and 252 [33%] with placebo), with a per-protocol population of 351 participants for immunogenicity analyses (303 in the VLA1553 group and 48 in the placebo group). 406 (54%) of all participants were female and 348 (46%) participants were male; the median age was 15·0 years, and the majority of participants were White (245 [33%]), followed by 214 (28%) other and 192 (26%) multiracial. In baseline seronegative participants, VLA1553 induced seroprotective chikungunya virus neutralising antibody levels in 248 of 251 participants (98·8% [95% CI 96·5–99·8]) 28 days after vaccination, which was sustained in 232 of 236 participants (98·3% [95·7–99·5]) at 12 months post-vaccination. VLA1553 was generally well tolerated, with the vast majority (2082 [97%] of 2155) of adverse events of mild or moderate intensity. When compared with placebo, participants exposed to VLA1553 had a significantly higher frequency of related adverse events (352 [70%] of 502 vs 122 [48%] of 252; p<0·0001), mostly headache, injection site pain, myalgia, fever, and fatigue. One serious adverse event of high-grade fever was classified possibly related to VLA1553. Among 81 adverse events of special interest (ie, symptoms suggesting chikungunya-like disease), 16 were classified as related to trial vaccination (15 in the VLA1553 group and one in the placebo group), mostly early onset events usually starting during the first week after vaccination. Late onset adverse events of special interest showed no medically relevant differences between treatment groups. Nine adolescents had short-lived, usually mild recurring episodes of arthralgia (seven with VLA1553 and two with placebo) with a median duration of 1 day (cumulative range 1–7 days). One further participant with a history of chikungunya virus infection experienced recurring arthralgia followed by long-term polyarthralgia in several joints starting 148 days post-vaccination, classified unrelated to VLA1553. None of the recurring events of arthralgia was medically attended.

Interpretation

VLA1553 was generally safe and induced seroprotective titres up to 12 months in nearly all adolescents, with favourable safety data in those who were seropositive. The data support the use of VLA1553 for the prevention of disease caused by the chikungunya virus among adolescents and in endemic regions.

Funding

Coalition for Epidemic Preparedness Innovations and EU Horizon 2020.

Translation

For the Portuguese translation of the abstract see Supplementary Materials section.

Source: 

Link: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00631-0/abstract?rss=yes

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The #epidemiology of #chikungunya virus in #Brazil and the potential #impact of #vaccines: a mathematical modelling study

 

Summary

Background

The first chikungunya virus (CHIKV) vaccine is now licensed in Brazil, the country that reports the most cases of CHIKV globally; however, the optimal use of the vaccine remains unclear owing to a poor understanding of CHIKV epidemiology and population immunity. We aimed to combine the distribution of cases and deaths reported since 2014 with seroprevalence studies to inform mathematical models that estimate the underlying rates of infection by state and year, and the underlying patterns of disease and death by age and sex.

Methods

We quantified the annual CHIKV infection and disease burden between 2014 and 2024 in each of the 27 federative units of Brazil using a mathematical model in a Bayesian framework that integrated serological surveys (n=12) and confirmed CHIKV disease cases (n=488 234) and CHIKV deaths (n=1719) reported between January, 2014, and September, 2024. Using this base, we estimated the potential impact of a vaccine over the period 2025–29 had the population been vaccinated before the 2025 season, evaluating different roll-out strategies.

Findings

We found that 18·3% (95% credible interval 16·5–20·3) of the Brazilian population has been infected since 2014, with the highest risk concentrated in the northeast and southeast. Overall, 1·13% (1·07–1·19) of infections were detected by surveillance systems, with an increasing probability of symptoms with age and greater risk of symptoms in females. Vaccinating 40% of the population older than 12 years (73 million doses), and assuming a vaccine efficacy of 70% against infection and 95% against disease, would avert up to 1·6 million (0·5–3) cases and 198 (61–359) deaths over the next 5 years.

Interpretation

Despite widespread circulation, most of Brazil remains susceptible to infection. CHIKV vaccination has the potential to substantially reduce disease burden.

Funding

CEPI.

Source: 

Link: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00605-X/fulltext?rss=yes

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History of Mass Transportation: A Henschel & Son 1936 Steam Locomotive

 

By Dornicke - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=5162139

Source: Wikipedia, https://en.wikipedia.org/wiki/Henschel_%26_Son

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Genomics insights reveal multi-year maintenance of a new #Deltacoronavirus infecting #Seabirds from Cagarras Island Archipelago Natural Monument, #Brazil

Abstract

Previous studies have identified various pathogens in seabirds, notably coronaviruses (CoVs) and influenza A viruses (IAVs), due to their potential to cause significant morbidity and mortality. The Cagarras Island Archipelago Natural Monument, located near Rio de Janeiro, Brazil, serves as nesting site for two species, the magnificent frigatebird (Fregata magnificens) and the brown booby (Sula leucogaster). Despite its ecological importance, no prior studies have investigated viral infections in these species, which share habitat interfaces with densely populated human areas. To address this gap, we sampled and tested seabirds for CoVs and IAVs from January 2022 to April 2024. Birds were captured and identified by species, age, and sex. Oropharyngeal and cloacal swabs, as well as blood samples, were collected. Viral RNA was extracted using the QIAamp Viral RNA Mini Kit, and the presence of IAVs was screened via real-time RT-PCR, while CoVs were screened using semi-nested RT-PCR. Sanger and metatranscriptomic sequencing were performed to identify viral strains and assess phylogenetic relationships. Of the 153 seabirds sampled, CoVs were detected in 6 individuals (9.1%) of F. magnificens and 16 individuals (18.4%) of S. leucogaster. No IAVs were found in either oropharyngeal or cloacal swabs, and all serum samples were negative for the presence of antibodies against the virus. We recovered two full deltacoronavirus genomes and eight additional draft genomes from S. leucogaster samples obtained from distinct sampling expeditions and additional enteroviruses, passeriviruses, and picornaviruses. Phylogenetic analysis revealed that the detected CoVs are closely related to avian deltacoronaviruses from environmental samples of S. leucogaster in the Sao Pedro and Sao Paulo Archipelago, indicating potential viral exchange between these seabird populations living at these distant islands. Moreover, multiple detections in different individuals at different time points are associated with specific Spike NTD deletions that have been shown to accumulate in immune escape lineages, supporting the long-term maintenance through new infections and reinfection of this virus in these bird populations. This is the first detection of CoVs in F. magnificens, highlighting their circulation in marine ecosystems. Further research is needed to understand the ecological and epidemiological implications, including potential cross-species transmission

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.06.19.660416v1

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#Neuroinvasive #Oropouche virus in a patient with #HIV from extra-Amazonian #Brazil

{Excerpt}

A novel reassortant Oropouche virus (OROV) lineage (with medium [M], large [L], and small [S] RNA segments: M1L2S2) has driven Brazil's largest and most geographically widespread OROV epidemic, expanding beyond the endemic Amazon basin to establish local transmission across multiple Brazilian states and other previously unaffected Latin American countries. The rapid spread of this lineage underscores its evolutionary potential and reinforces its significance as a public health threat.1 Similar to chikungunya and Zika viruses, expanding arboviruses can exhibit unexpected clinical and epidemiological shifts, including vertical transmissions, neuroinvasive effects, and potentially fatal outcomes.2–4 Although OROV typically causes self-limited febrile illness, accumulating clinical and experimental evidence suggests neurotropic potential.5 This Correspondence describes the first confirmed case of neuroinvasive OROV infection caused by the emergent M1L2S2 lineage in extra-Amazonian Brazil, highlighting a potential synergistic mechanism of CNS invasion facilitated by HIV-induced immune dysregulation.

(...)

Source: Lancet Infectious Diseases, https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00352-4/fulltext?rss=yes

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#Brazil’s First #H5N1 #Outbreak in Commercial #Poultry: A #Sentinel Event for Cross-Border #Preparedness

Highlight

Brazil’s first confirmed H5N1 outbreak in commercial poultry marks a critical shift in South America’s avian influenza landscape. The event calls for strengthened coordination between animal and human health sectors, improved border surveillance, and early-warning systems to reduce zoonotic risk in regions with growing poultry production and international connectivity.

Source: Journal of Travel Medicine, https://academic.oup.com/jtm/advance-article-abstract/doi/10.1093/jtm/taaf050/8153894?redirectedFrom=fulltext

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Emergence of #Oropouche Virus in Espírito Santo State, #Brazil, 2024

Abstract

Oropouche virus (OROV), historically endemic to the Amazon, had spread to nearly all Brazil states by 2024; Espírito Santo emerged as a transmission hotspot in the Atlantic Forest biome. We characterized the epidemiologic factors driving OROV spread in nonendemic southeast Brazil, analyzing environmental and agricultural conditions contributing to viral transmission. We tested samples from 29,080 suspected arbovirus-infected patients quantitative reverse transcription PCR for OROV and dengue, chikungunya, Zika, and Mayaro viruses. During March‒June 2024, the state had 339 confirmed OROV cases, demonstrating successful local transmission. Spatial analysis revealed that most cases clustered in municipalities with tropical climates and intensive cacao, robusta coffee, coconut, and pepper cultivation. Phylogenetic analysis identified the Espírito Santo OROV strains as part of the 2022–2024 Amazon lineage. The rapid spread of OROV outside the Amazon highlights its adaptive potential and public health threat, emphasizing the need for enhanced surveillance and targeted control measures.

Source: US Centers for Disease Control and Prevention, https://wwwnc.cdc.gov/eid/article/31/6/24-1946_article

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#Brazil, Ministry of #Health rules out case of {#H5N1} #birdflu virus infection in a #worker from Rio Grande do Sul

The Ministry of Health reports that a suspected case of Avian Influenza has been ruled out in a worker at a farm in the municipality of Montenegro (RS), where an outbreak of the disease was identified in birds. 

On the afternoon of Tuesday (20/05), Fiocruz, the reference laboratory for this type of analysis, confirmed that the test for the disease was negative. At this time, there are no other suspected or under investigation cases in Brazil.

The Ministry of Health, together with the State Health Department of Rio Grande do Sul, is monitoring all people who may have been exposed to the virus through direct contact with infected birds to monitor their health status, start treatment immediately at the first symptoms and preventative surveillance of possible contacts. 

There are no records of transmission of the disease from one person to another worldwide.

The risk of human infection is low and does not occur through the consumption of meat or eggs, but rather through direct contact with sick birds or contaminated environments. Therefore, the most effective preventive measure is to avoid contact with dead or sick birds.

The Ministry of Health is working with the Ministry of Agriculture and Livestock (Mapa) and the State Health Department of Rio Grande do Sul to provide all necessary support for actions related to the first case of bird flu on a commercial farm in the municipality of Montenegro (RS). 

To ensure a rapid response to possible outbreaks, the Ministry of Health launched, in December 2024, the National Contingency Plan for the Health Sector for Avian Influenza, which guides the ministry's actions, including integrated surveillance, laboratory diagnosis, assistance and health communication. 

In this sense, Brazil is working on different fronts to prepare for a possible risk of cases in humans. The Ministry of Health, through the SUS , has the capacity to perform laboratory tests, maintains a stock of the medicine to treat the different types of influenza (Oseltamivir) and, if necessary, has the technology to produce vaccines. 

Understand how the suspected case was ruled out

The investigation into the suspected case began on May 18, when the worker at the Montenegro (RS) farm, who was already being monitored by state surveillance and the Ministry of Health, showed the first symptoms. Treatment began immediately and the sample was sent to Fiocruz, in Rio de Janeiro.

The PCR test was initially performed, which identifies specific genetic material from the influenza virus – if positive, other tests are performed to identify the type of influenza, including avian flu. In the case in question, the initial test was negative for any type of influenza.

For those who work with wild animals, it is recommended to use Personal Protective Equipment (PPE) after identifying infected animals or those with symptoms suggestive of avian influenza, such as gloves, N95 mask or higher and eye protection, in addition to care such as hand hygiene, avoiding touching eyes, mouth and nose and changing clothes after contact with infected animals.

Ministry of Health 

Source: Ministry of Health, https://www.gov.br/saude/pt-br/assuntos/noticias/2025/maio/ministerio-da-saude-descarta-caso-de-gripe-aviaria-em-um-trabalhador-do-rio-grande-do-sul

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#Brazil - #Influenza A #H5N1 viruses of high pathogenicity (Inf. with) (non-poultry including wild birds) (2017-) - Immediate notification

 The Official Veterinary Services (OVS) received a notification of acute mortality and neurological signs in swans in a zoo. Laboratory analysis identified H5N1 virus clade 2.3.4.4b. OVS is conducting an epidemiological investigation of the event.

Source: WOAH, https://wahis.woah.org/#/in-review/6485

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#Brazil - High pathogenicity avian #influenza #H5N1 viruses (#poultry) (Inf. with) - Immediate notification

 

The Official Veterinary Services (OVS) received a notification of acute mortality, neurological and digestive signs in a breeder farm. From the start of the OVS investigation, the premise was quarantined, including suspension of the movement of birds and products. Laboratory analysis identified H5N1 virus clade 2.3.4.4b. OVS is conducting an epidemiological investigation of the event and implementing the restrictions and measures in accordance with the National Contingency Plan for high pathogenicity avian influenza (HPAI).

Source: WOAH, https://wahis.woah.org/#/in-review/6484

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Yellow fever - Region of the #Americas (#WHO D.O.N., May 16 '25)

{Summary}

Situation at a glance

From 29 December 2024 and as of 26 April 2025 (with data for Ecuador updated as of 2 May 2025), a total of 212 confirmed human cases of yellow fever, including 85 deaths, have been reported to WHO by five countries in the Region of the Americas (case fatality rate (CFR) 40%). 

The cases have been reported in the Plurinational State of Bolivia, Brazil, Colombia, Ecuador and Peru. 

The 212 confirmed yellow fever cases reported so far in 2025 represent a threefold increase compared to the 61 confirmed cases reported in 2024. 

WHO is supporting affected countries in implementing coordinated actions to respond to the yellow fever cases and outbreaks. 

This includes: 

- enhancing preventive measures, 

- strengthening surveillance and case management, 

- improving risk communication and community engagement, and 

- implementing immunization activities. 

The current yellow fever situation in the Americas is driven by increased sylvatic transmission cycles. 

The occurrence of yellow fever cases outside of the Amazon basin, combined with high fatality, varying vaccination coverage across affected countries, and limited vaccine supply, contributes to the overall classification of yellow fever risk in the Region of the Americas, especially in endemic countries, as high. 

WHO emphasizes the importance of active surveillance, timely laboratory testing, cross-border coordination, and information sharing. 

Vaccination remains the primary means for the prevention and control of yellow fever. 

WHO continues to support countries in expanding vaccination coverage through routine immunization programs and mass vaccination campaigns to enhance population immunity and reduce the risk of outbreaks.

(...)

Source: World Health Organization, https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON570

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