#WNV in #humans, the European Region, Weekly #Report (ECDC, July 17 '26): #Italy (21), #Greece (7), North #Macedonia (2), #Romania (2) & #Spain (2) cases so far

 

{Excerpt}

Week 29, 2026 | Produced on 17 July 2026 at 08:30, based on data submitted up until and including 15 July 2026.

Current situation

    ° Since the beginning of the 2026 transmission season, and as at 15 July, 28 areas affected by West Nile virus (WNV) have been identified in five countries across Europe {1}.

    ° These areas are located in: 

        § Italy (17), 

        § Greece (five), 

        § North Macedonia (two), 

       § Romania (two) and 

        § Spain (two).

    ° The five countries have reported 34 locally acquired {2} human cases of WNV infection: 

        § Italy has reported 21, 

        § Greece seven,     

        § North Macedonia two, 

        § Romania two and 

        § Spain two cases.

    ° This week, 17 areas are reported as affected for the first time this season. The affected areas identified as at 15 July 2026 are listed in Table 1 and shown in Map 1 below.

(...)

Table 1. Areas affected by West Nile virus during the 2026 transmission season at 15 July, by country and NUTS3 or GAUL1 area

{Click on Images to Enlarge}

__

* ‘First reported this week’ indicates that the affected area was not included in the previous weekly overview.

(...)

Source: 

Link: https://wnv-weekly.ecdc.europa.eu/

____

Seasonal #surveillance in #humans in 2026 for #WNV - Update (ECDC, July 10 '26): #Italy reported 6 cases, #Macedonia 2, #Romania 2, #Greece 1, #Spain 1

 

Week 28, 2026 | Produced on 9 July 2026 at 08:45, based on data submitted up to 8 July 2026.

Current situation

    ° Since the beginning of the 2026 transmission season, and as of 8 July, 11 areas affected by West Nile virus (WNV) have been identified in five countries across Europe {1}.

    ° These areas are located in: 

        - Italy (five), 

        - North Macedonia (two), 

        - Romania (two), 

        - Greece (one) and 

        - Spain (one).

    ° The five countries have reported 12 locally acquired {2} human cases of WNV infection: 

        - Italy has reported six, 

        - North Macedonia two, 

        - Romania two, 

        - Greece one and 

        - Spain one case.

    ° This week, five areas are reported as affected for the first time this season. 

(...)

Table 1. Areas affected by West Nile virus during the 2026 transmission season as of 8 July, by country and NUTS3 or GAUL1 area

{Click on Image to Enlarge}

(...)

__

{*} ‘First reported this week’ indicates that the affected area was not included in the previous weekly overview.

{1} European Union/European Economic Area countries and selected EU-neighbouring countries (Albania, Bosnia and Herzegovina, Kosovo**, Montenegro, North Macedonia, Serbia and Türkiye).

{**} This designation is without prejudice to positions on status and is in line with UNSCR 1244/1999 and the ICJ Opinion on the Kosovo declaration of independence.↩︎

{2} Cases acquired within the reporting country.↩︎

(...)

Source: 

Link: https://www.ecdc.europa.eu/en/west-nile-fever/surveillance-and-disease-data/disease-data-ecdc

____

#Taiwan CDC: The #WMO predicts a strong #ElNiño event this year, which is conducive to spread of #arboviral diseases (July 7 '26)

 

    The latest forecast from the World Meteorological Organization (WMO) indicates that El Niño may intensify further in the coming months, potentially developing into a strong El Niño. 

    El Niño could further raise global temperatures and alter atmospheric circulation and rainfall patterns, increasing the risk of extreme weather events. 

    Some regions may face disasters such as short-duration heavy rainfall, torrential rain, and flooding due to more concentrated rainfall, while other regions may experience drought and water shortages. 

    International research shows that the high temperatures, warm winter, and abnormal rainfall brought about by El Niño may affect the growth and reproduction of disease-carrying mosquitoes, increasing the risk of dengue fever transmission. 

    Rising temperatures may shorten the growth cycle of disease-carrying mosquitoes, accelerating their reproduction rate; high temperatures may also shorten the time required for the dengue virus to multiply in mosquitoes to become infectious, increasing the chances of virus transmission. 

    On the other hand, after heavy rainfall, torrential rain, or continuous rainfall, various types of stagnant water environments easily form both indoors and outdoors, increasing the breeding opportunities for disease-carrying mosquitoes. 

    Due to the El Niño phenomenon facilitating dengue fever transmission and the ongoing international outbreaks of dengue fever and other mosquito-borne infectious diseases, coupled with the peak summer travel season, the public is urged to take mosquito prevention measures while traveling abroad and seek medical attention immediately if they experience any symptoms upon returning home, in order to jointly prevent dengue fever.

    Data from the Centers for Disease Control and Prevention (CDC) shows that as of July 6th this year, there have been a total of 83 confirmed dengue fever cases, including 7 local cases, all residing in Kaohsiung City; and 76 imported cases, all from Southeast and South Asian countries, with Indonesia (21 cases) being the most numerous, followed by the Maldives (14 cases) and Vietnam (11 cases). 

    The cumulative number of cases this year is lower than the same period last year (2025) (91 cases). 

    The global dengue fever outbreak remains severe, with over 1.44 million cases reported as of May this year. 

    The majority of cases are in the Americas, with Brazil having the highest number, followed by Bolivia and Colombia. 

    Neighboring Asian countries such as Vietnam, Malaysia, Sri Lanka, Cambodia, Bangladesh, and Laos have recently seen an increase in cases, with many exceeding the number from the same period last year, and showing a trend of co-circulation of multiple serotypes (DENV). 

    Given the current rainy season in Southeast Asia, the overall outbreak is expected to remain at its peak. 

    Health authorities are closely monitoring mosquito density in communities and strengthening patrols and prevention efforts in high-risk areas.

    The Centers for Disease Control (CDC) explained that with recent persistent high temperatures and frequent afternoon thunderstorms across Taiwan, post-rain environmental cleanup is crucial for dengue fever prevention. 

    Residents should proactively inspect their homes and surrounding areas, thoroughly removing water-collecting containers such as flowerpot saucers, discarded tires, and other stacked items. 

    Unused containers should be turned upside down or properly stored. A second inspection should be conducted after rain to ensure thorough cleaning and prevent mosquitoes from laying eggs and breeding.

    The Taiwan Centers for Disease Control (CDC) reminds the public that the current climate is suitable for mosquito breeding and activity. 

    When engaging in outdoor activities, the public is advised to wear light-colored long-sleeved clothing and use government-approved mosquito repellents containing effective ingredients such as DEET, Picaridin, or Imamectin (IR-3535). 

    If you experience symptoms resembling dengue fever, such as fever, headache, retro-orbital pain, or muscle and joint pain, please seek medical attention immediately and inform your doctor of your travel history. 

    Medical institutions are also urged to be vigilant, implement TOCC (travel, occupation, contact, and social contact) inquiries, use the dengue NS1 rapid test kit to aid diagnosis, and report cases promptly to facilitate timely prevention and control measures by health authorities. 

    Furthermore, given the ongoing international dengue fever outbreak, if you experience symptoms resembling dengue fever, such as fever, headache, muscle and joint pain, or rash upon arrival in Taiwan, please inform airport quarantine personnel. 

    For information related to dengue fever, please visit the Taiwan Centers for Disease Control website (https://www.cdc.gov.tw) or call the toll-free epidemic prevention hotline 1922 (0800-001922).

Source: 

Link: https://www.cdc.gov.tw/Bulletin/Detail/iheCGS59dCugdGfswWuh5Q?typeid=9

____

Surveillance for West NileVirus Infections in Humans in Europe, Weekly Report: Week 26, 2026 (ECDC, summary)

 

{Excerpt}

Epidemiological summary

    Since the beginning of 2026, and as of 24 June, two countries in Europe reported three human cases{1} of West Nile virus (WNV) infection: Italy (two cases) and North Macedonia (one case).

    The current report in Table 1 includes the number of probable and confirmed cases of WNV infections per NUTS3 region. However, these figures are preliminary and should be interpreted with caution as they may be revised by the countries as more information becomes available. For further details on case numbers, please refer to the joint monthly report, which offers a more detailed analysis.

    Please note: The table and map in this report contain countries and areas where human West Nile virus infection cases were reported to EpiPulse Cases.

(...)

#) Country

    ° Affected area*

        § Newly affected area**

            - Number of probable cases - Number of confirmed cases - Total cases 

1) Italy

    ° Caserta

        § No

            - 0 / 1 /1 

    ° Firenze

         § No

            - 0 / 1 /1 

2) North Macedonia

    ° Vardarski

        § No

            - 0 / 1 / 1

__

{*} An ‘affected area’ or ‘risk area’ is defined as ‘a risk area with ongoing transmission of WNV to humans’. This means that at least one autochthonous human case of WNV has been reported as a result of local transmission in the area according to the agreed, standardised and disease-specific case definition. In exceptional circumstances, a probable case can be used to determine transmission, however, this should only apply in specific and agreed situations when a case cannot be confirmed within a reasonable time.

{**} Compared to the previous weekly report.

(...)

Source: 

Link: https://wnv-weekly.ecdc.europa.eu/

____

Yellow #fever - #Global (WHO, D.O.N., June 24 '26, summary)

 

Situation at a glance

    Yellow fever is a viral disease found in areas of Africa and the Americas, spread by infected mosquitoes. 

    Following an increase of cases in the Americas in 2025, transmission activity remained into 2026. 

    From 1 January to 26 May 2026, six countries reported a total of 79 human infections along with multiple epizootics, indicating active sylvatic circulation. 

    In Africa, sustained activity continued across parts of the region, affecting 13 high-risk countries (as per classification in the Eliminate Yellow fever Epidemics (EYE) Strategy). 

    From January to May 2026, three countries in Africa reported 16 confirmed human cases, with an additional 32 suspected cases under investigation in five other countries. 

    The recent rapid risk assessment assessed geographical variations in vaccination coverage, evidence of viral circulation, and the presence of competent vectors, concluding that unvaccinated populations in countries or areas with a history of yellow fever transmission remain at greatest risk. 

    Transmission dynamics are further influenced by seasonal ecological factors, particularly rainfall, temperature, and mosquito abundance. 

    Outbreaks reported from October 2025 through May 2026 in countries or areas with a history of yellow fever transmission were generally consistent with seasonal patterns or reflected gaps in immunization coverage. 

    In contrast, cases detected in previously unaffected areas suggest viral introduction and an increased risk of urban transmission. 

    No imported cases were detected outside the two affected WHO regions, but expanding vector suitability, rapid urbanization, climate shifts, and increased mobility continue to create conditions conducive to international spread. 

    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 programmes and preventive vaccination campaigns to enhance population immunity and reduce the risk of outbreaks.

(...)

Source: 

Link: https://www.who.int/emergencies/disease-outbreak-news/item/2026-DON610

____

#Surveillance of West Nile Virus {#WNV} #Human #Infections in #Europe, Weekly Report (ECDC, Jun. 18 '26): First two cases reported in #Italy

 

Epidemiological summary

    Since the beginning of 2026, and as of 17 June, 2 countries in Europe reported 3 human cases of West Nile virus infection: Italy and North Macedonia.

    The current report in Table 1 includes the number of probable and confirmed cases of WNV infections per NUTS region. 

    However, these figures are preliminary and should be interpreted with caution as they may be revised by the countries as more information becomes available. 

    Consequently, no totals are provided. 

    For further details on case numbers, please refer to the joint monthly report, which offers a more detailed analysis.

    Please note: The table and map in this report contain countries and areas where human West Nile virus infection cases were reported to EpiPulse Cases.

Introduction

    The European Centre for Disease Prevention and Control (ECDC) provides a weekly overview of human cases of West Nile virus (WNV) infection to support the competent authorities responsible for blood safety. 

    This overview can aid decisions on the deferral or testing of blood donors who may have been exposed to the virus, in accordance with Commission Directives 2004/33/EC and 2014/110/EU.

    West Nile virus infection in humans is a notifiable disease at the EU level and cases are reported in accordance with the EU case definition. 

    The table and map in this report show the countries and areas where human cases of WNV infection have been reported to the European surveillance portal for infectious diseases (EpiPulse Cases).

    More information on the occurrence of WNV infection among humans in Europe, as well as WNV outbreaks among equids and birds, is available in the joint monthly report produced by ECDC and the European Food Safety Authority (EFSA).

    Here we present the weekly report as of 17 June 2026.

Overview of West Nile virus cases in EU/EEA and EU-neighbouring countries

Table 1. Countries and regions with locally acquired human cases of West Nile virus infections in 2026 as of 17 June.

[Country

    ° Affected Region

        § Newly Affected Region

           * No. of Probable / Confirmed / Total Cases]

Italy

    ° Caserta

        § Yes

            * 0 / 1 / 1

    ° Firenze

        § Yes

            * 0 / 1 / 1

Macedonia

    ° Vardarski

        § No

            * 0 / 1 / 1

(...)

Source: 

 Link: https://wnv-weekly.ecdc.europa.eu/

____

Yellow Fever - Global Rapid #Risk #Assessment (WHO, June 17 '26, summary)

 

{Summary}

Overall Risk Statement 

    This rapid risk assessment (RRA) aims to assess the overall public health risk at the global level associated with the increase in yellow fever (YF) transmission in the Region of the Americas alongside ongoing YF activity reported in the WHO African Region, documented from the fourth quarter of 2025 through 2026 to date.  

    Together these events involve 13 out of the 40 countries with areas at high risk for YF transmission globally (currently 27 in Africa and 13 in the Americas under the Global Strategy to Eliminate Yellow Fever Epidemics (EYE) classification). 

    For this risk assessment, the WHO Secretariat considered the public health impact of YF, the risk of geographical spread to other WHO regions, and the risk associated with insufficient control capacities. 

    This RRA also provides an assessment of the overall risk in regions with a history of YF transmission, and other regions where the primary vector for urban YF transmission (Aedes aegypti) is present. 

    The overall public health risk also incorporates differences in vaccination status and the availability of epidemiological evidence of YF or arboviral circulation. 

    Unvaccinated populations in at-risk areas constitute the highest risk group; vaccinated populations in the same areas are considered low risk; and populations in areas with no available evidence of YF or indicative arboviral circulation are classified as low risk, albeit with low confidence due to limited surveillance data. 

    The assessment further integrates seasonal ecological dynamics, recognizing that although YF virus transmission can occur year-round in certain ecological zones, marked intra-annual variability exists. 

    In addition, the RRA assesses the risk to countries who do not have competent vectors, as well as the risk to travellers, considering their YF vaccination status. 

    YF outbreaks must be interpreted within their epidemiological and geographic context, as the dynamics of transmission, population immunity, and public health implications differ markedly between high risk and non- risk areas for YF transmission. 

    In high-risk areas, where the virus circulates continuously and population immunity varies, outbreaks may reflect seasonal patterns, gaps in routine immunization, or fluctuations in vector populations. 

    In contrast, outbreaks occurring in areas with no evidence available for YF—where population immunity is typically low and YF virus is not expected to circulate—raise additional concerns regarding viral introduction, the potential for rapid urban transmission, and the need for immediate vaccination and vector control measures, especially in urban settings, to prevent wider spread. 

    Understanding these contextual differences is essential for interpreting the epidemiology, identifying risk factors for severe disease, and determining the relevance and effectiveness of prevention and control strategies. 

(...)

Source: 

Link: https://www.who.int/publications/m/item/who-rapid-risk-assessment--yellow-fever--global-v.1

____

#Surveillance of West Nile Virus #WNV #infections in #human in #Europe, Weekly Report (ECDC, June 12 '26)

 

Week 24, 2026

Produced on 11 June 2026 at 08:15 based on data submitted up to 10 June 2026

Epidemiological summary

    Since the beginning of 2026, and as of 10 June, 1 country in Europe reported 1 human case of West Nile virus infection: North Macedonia.

    The current report in Table 1 includes the number of probable and confirmed cases of WNV infections per NUTS3 region. However, these figures are preliminary and should be interpreted with caution as they may be revised by the countries as more information becomes available. Consequently, no totals are provided. For further details on case numbers, please refer to the joint monthly report, which offers a more detailed analysis.

    Please note: The table and map in this report contain countries and areas where human West Nile virus infection cases were reported to EpiPulse Cases.

Introduction

    The European Centre for Disease Prevention and Control (ECDC) provides a weekly overview of human cases of West Nile virus (WNV) infection to support the competent authorities responsible for blood safety. This overview can aid decisions on the deferral or testing of blood donors who may have been exposed to the virus, in accordance with Commission Directives 2004/33/EC and 2014/110/EU.

    West Nile virus infection in humans is a notifiable disease at the EU level and cases are reported in accordance with the EU case definition. The table and map in this report show the countries and areas where human cases of WNV infection have been reported to the European surveillance portal for infectious diseases (EpiPulse Cases).

    More information on the occurrence of WNV infection among humans in Europe, as well as WNV outbreaks among equids and birds, is available in the joint monthly report produced by ECDC and the European Food Safety Authority (EFSA).

    Here we present the weekly report as of 10 June 2026.

Overview of West Nile virus cases in EU/EEA and EU-neighbouring countries

{Country - Affected Region - Probable - Confirmed - Total Cases}

    ° North Macedonia - Vardarski - 0 - 1 - 1

(...)

Source: 

Link: https://wnv-weekly.ecdc.europa.eu/

____

Susceptibility of wild and domestic #songbirds to #Usutu virus

Abstract

Usutu virus (USUV) is an emerging mosquito-borne orthoflavivirus that can cause neuroinvasive disease in humans and wild birds. USUV clusters phylogenetically within the Japanese encephalitis virus serocomplex, sharing antigenic and ecological similarity with West Nile virus (WNV). USUV is maintained in an enzootic cycle primarily involving passerine birds and Culex spp. mosquitoes. USUV was first isolated in South Africa in 1959 and has since spread throughout Africa and Europe, causing mortality and disease in several wild bird populations, specifically the Eurasian blackbird (Turdus merula). To understand transmission and pathogenesis of USUV in birds, we sought to develop passerine bird models of infection using wild-caught house finches (Haemorhous mexicanus), wild-caught American robins (Turdus migratorius), domestic canaries (Serinus canaria domestica), and captive-bred zebra finches (Taeniopygia guttata). Birds were inoculated with one or two isolates of USUV and viremia was measured. House finches, American robins, and canaries were susceptible to USUV, with 100% of inoculated birds developing viremia. These avian species reach viremias that have the potential to infect Cx. quinquefasciatus mosquitoes. Clinical disease and histopathological evidence of disease were severe in American robins and moderate to severe in canaries, with limited disease in house finches. However, zebra finches inoculated with one isolate of USUV did not develop detectable viremia. These findings provide additional tools for studying USUV enzootic transmission and pathogenesis in passerine birds.

Source: 

Link: https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0014213

____

#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

____

#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

____

An ultrapotent #human #antibody neutralizes all maturation states of #Zika virus

 

Significance

Zika virus causes microcephaly in fetuses and no vaccines or therapeutics currently exist against it. Mature and immature flavivirus particles are infectious. Here, we showed the cryoelectron microscopy (cryoEM) structures of an ultrapotent A9E human antibody, complexed with both mature (mZIKV) and immature (immZIKV) Zika virus, and the antibody neutralization mechanism. One important characteristic is that Fab A9E can distort both mZIKV and ImmZIKV particle structures. Additionally, Fab A9E or IgG A9E LALA mutant can abolish or reduce the overall infection to myeloid cells when added to other infection enhancing antibody DV62.5:immZIKV complexes. Thus, antibody A9E represents a promising potential prophylactic and therapeutic candidate, as it is effective against all maturation states of Zika virus.

Abstract

Zika virus (ZIKV), a flavivirus, causes a range of clinical complications including microcephaly in human fetuses. Currently, there is no treatment or vaccine. Different maturation states (mature and immature forms) of flavivirus particles have been observed to be released from infected cells and are infectious. To understand how an ultrapotent human antibody (HMAb) A9E can neutralize these Zika particles, we determined the cryoEM structures of the A9E Fab fragment complexed with mature (mZIKV) and immature (immZIKV) ZIKV to 2.8Å and 7.5Å, respectively. A9E binds to an epitope spanning Domain I (EDI), EDIII, and their linker in an E protein protomer in both immZIKV and mZIKV particles. A9E generally inhibited prior to or during virus attachment to cells, via virus aggregation, distortion of virus particles and inhibition of receptor binding. ImmZIKV is particularly sensitive to structural distortion by Fab A9E. The primary mode of infection used by ImmZIKV is via antibody-dependent enhancement of infection (ADE)—the formation of virus complex with nonneutralizing or subneutralizing concentrations of antibodies, that leads to enhanced infection of Fcγ positive myeloid cells. IgG A9E, by itself displays poor ADE activity. When IgG LALA mutant or Fab A9E is added to other enhancing antibody (DV62.5):virus complexes, they can strongly reduce the overall ADE activity. This is likely due to their ability to distort virus particle structure, suggesting that HMAb A9E could be a potential prophylactic and therapeutic candidate against all maturation states of ZIKV.

Source: 

Link: https://www.pnas.org/doi/abs/10.1073/pnas.2502522122?af=R

____

#Kyasanur Forest #disease: an emerging #arboviral #threat

 

Summary

Kyasanur Forest disease is a neglected tick-borne viral haemorrhagic fever endemic to India's Western Ghats, caused by the Kyasanur Forest disease virus, a flavivirus transmitted by Haemaphysalis spinigera ticks. The virus circulates in a sylvatic cycle among monkeys, rodents, shrews, birds, and ixodid ticks, and is transmitted to humans incidentally via tick bites. Since its discovery in 1957 in Karnataka, Kyasanur Forest disease has spread to other Indian states, driven by deforestation, forest fragmentation, and increased human incursion into wildlife habitats. Clinically, the disease manifests in a biphasic pattern, with haemorrhagic and neurotropic presentations. Although a formalin-inactivated vaccine is available, its efficacy is not promising, and no antivirals have been approved to date. Field reports indicate that mortality in monkeys might serve as an early indicator of forthcoming human outbreaks. The transmission dynamics of Kyasanur Forest disease, diagnostic gap, and ecological complexities present substantial public health challenges. In this Review, we provide an update on Kyasanur Forest disease virus, covering its epidemiology, transmission dynamics, molecular virology, virus–host interactions, immunological responses, animal models, and potential antiviral therapies and vaccines.

Source: Lancet Infectious Diseases, https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00589-4/abstract?rss=yes

____

#Italy, #WNV & #USUV Integrated #Surveillance - Weekly Bulletin No. 16 - 30 October 2025 (Summary)

 

{Summary}

-- During current epidemiological week (from 23 to 29 Oct. 2025), two new human cases of infection with West Nile Virus have been reported. 

-- The cumulative number of confirmed cases this season so far rose to 773 (they were 771 last week), of these: 

- 367 were West Nile Neuroinvasive Disease (WNND): 17 in Piedmont, 56 Lombardy, 35 Veneto, 4 Friuli-Venezia Giulia, 1 Liguria, 30 Emilia-Romagna, 11 Tuscany, 1 Marche, 87 Latium, 2 Molise, 83 Campania, 2 Apulia, 2 Basilicata, 5 Calabria, 3 Sicily, 28 Sardinia, 

- 56 were asymptomatic cases detected in blood donors, 

- 339 were West Nile Fever cases (of which: 1 imported from Kenya, 1  from Egypt and 1 from Maldives), 

- 3 asymptomatic cases, 

- 8 unspecified cases. 

-- Among confirmed cases, 72 fatalities have been recorded: 7 in Piedmont, 9 Lombardy, 1 Veneto, 2 Emilia-Romagna, 1 Marche, 19 Latium, 29 Campania, 2 Calabria, 1 Sicily, 1 Sardinia. 

- The Case-Fatality Rate in WNND cases is 19.6% (it was 20% in 2018, 14% in 2024). 

-- Since the start of the epidemic season, 11 confirmed human cases of Usutu virus infection were reported: 2 in Piedmont, 3 Lombardy, 2 Veneto, 1 Tuscany, 3 Latium.

(...)

Source: High Institute of Health, https://www.epicentro.iss.it/westnile/bollettino/Bollettino_WND_2025_16.pdf

____

Detection of #WNV, #USUV and #Insect-Specific #Bunyaviruses in #Culex spp. Mosquitoes, #Greece, 2024

 

Abstract

Greece is one of the countries in Europe most affected by West Nile virus (WNV), and since 2010, when the virus caused a large outbreak with 197 human neuroinvasive cases, outbreaks occur almost every year. Mosquito surveillance is an indirect sign of virus circulation; therefore, the purpose of the study was the molecular detection of WNV in 45,988 C. pipiens s.l. mosquitoes collected during 2024 in four Regions of Greece and the genetic characterization of the virus strains. WNV was detected in 41 of 1316 (3.12%) Culex spp. mosquito pools. Next-generation sequencing was applied to the WNV-positive samples that had a high viral load. All WNV sequences belong to Cluster B of the sub-lineage Europe WNV-2A presenting a temporal clustering. The WNV infection rates varied highly across the Regions, regional units and months, being higher in Thessaly and Central Macedonia Regions, especially in July and September. All mosquito pools were also tested for Usutu virus (USUV), and one pool was found positive, with sequence clustering into the EU-2 lineage. A subset of mosquitoes (737 pools) was tested for additional viruses, and bunya-like viruses were detected in 6 pools with sequences clustering into four distinct subclades. The prompt detection of pathogenic viruses is helpful for the design of control measures, while the detection of insect-specific viruses provides insights into viral diversity and evolution.

Source: Viruses, https://www.mdpi.com/1999-4915/17/11/1414

____

#Italy, #WNV & #USUV Integrated #Surveillance - Weekly Bulletin No. 14, 15 Ocotber 2025 (ISS, edited)

 

{Summary}

-- New human cases of West Nile Virus infection continue to be reported albeit with reduced intensity. 

-- During current epidemiological week (from 9 to 15 October 2025) 26 new confirmed cases have been reported. 

-- The total number of cases so far is 767 (they were 740 last week), of these: 

- 366 were West Nile Neuroinvasive Disease (WNND): 17 in Piedmont, 56 Lombardy, 34 Veneto, 4 Friuli-Venezia Giulia, 1 Liguria, 32 Emilia-Romagna, 10 Tuscany, 1 Marche, 86 Latium, 2 Molise, 83 Campania, 2 Apulia, 2 Basilicata, 5 Calabria, 3 Sicily, 28 Sardinia, 

- 57 were asymptomatic cases among blood donors, 

- 333 were West Nile Fever cases (of which 1 imported from Kenya, 1 from Egypt and 1 from Maldive), 

- 3 asymptomatic cases, 

- eight unspecified cases. 

-- Among confirmed cases, 69 fatalities have been reported: 7 in Piedmont, 9 Lombardy, 2 Emilia-Romagna, 18 Latium, 29 Campania, 2 Calabria, 1 Sicily, 1 Sardinia. 

-- The case-fatality rate in WNND cases stands at 18.8% (in 2018 it was 20%, in 2024 it was 14%). 

-- So far this season, 10 cases of Usutu virus infection have been recorded: 2 in Piedmont, 3 Lombardy, 2 Veneto, 3 Latium.

(...)

Source: High Institute of Health, https://www.epicentro.iss.it/westnile/bollettino/Bollettino_WND_2025_14.pdf

____

#Italy, Integrated #WNV & #USUV #Surveillance - Weekly Bulletin No. 13, 9 October 2025 (Summary): 22 new confirmed cases

{Summary}

-- During current epidemiological week, a rise in the West Nile Virus human cases has been observed although with reduced intensity compared most recent weeks. 

-- Twenty-two new confirmed human cases have been reported during surveillance week from 2 to 8 October 2025. 

-- The cumulative number of cases rose to 740 (they were 718 last week), of these: 

- 354 were West Nile Neuroinvasive Disease (WNND): 16 in Piedmont, 53 Lombardy, 33 Veneto, 4 Friuli-Venezia Giulia, 1 Liguria, 30 Emilia-Romagna, 11 Tuscany, 1 Marche, 84 Latium, 2 Molise, 81 Campania, 2 Apulia, 2 Basilicata, 5 Calabria, 3 Sicily, 26 Sardinia,

- 57 were asymptomatic cases in blood donors, 

- 318 were West Nile Fever cases, of which 1 imported from Kenya, 1 from Egypt and 1 from Maldives, 

- 4 asymptomatic cases, 

- 7 unspecified cases. 

-- Among confirmed cases there were 68 fatalities: 7 in Piedmont, 9 Lombardy, 2 Emilia-Romagna, 18 Latium, 28 Campania, 2 Calabria, 1 Sicily, 1 Sardinia. 

- The Case-Fatality Rate in WNND cases is now at 19.2% (it was 20% in 2018 and 14% in 2024). 

-- During current epidemic season, ten Usutu Virus human cases have been confirmed: 2 in Piedmont, 3 Lombardy, 2 Veneto, 3 Latium.

(...)

Source: High Institute of Health, https://www.epicentro.iss.it/westnile/bollettino/Bollettino_WND_2025_13.pdf

____

#Italy, Integrated #WNV & #USUV #Surveillance - Weekly Bulletin No. 12, 2 October 2025: 38 new confirmed cases (Summary)

 

{Summary}

-- During current epidemiological week (from 25 September to 1rst October 2025), 38 new confirmed human infection with West Nile Virus have been reported. 

-- Since the beginning of the epidemic season, 718 confirmed cases have been recorded in Italy (they were 680 in the last bulletin), of these: 

- 341 were West Nile Neuroinvasive Disease (WNND): 15 in Piedmont, 51 Lombardy, 30 Veneto, 4 Friuli-Venezia Giulia, 1 Liguria, 27 Emilia-Romagna, 11 Tuscany, 1 Marche, 84 Latium, 2 Molise, 79 Campania, 2 Apulia, 2 Basilicata, 5 Calabria, 2 Sicily, 25 Sardinia, 

- 57 were asymptomatic cases in blood donors, 

- 309 were West Nile Fever cases (1 imported from Kenya, 1 Egypt, and one Maldives), 

- 4 asymptomatic cases, 

- 7 unspecified cases. 

-- Among confirmed cases, there have been 49 fatalities: 7 in Piedmont, 5 Lombardy, 2 Emilia-Romagna, 18 Latium, 14 Campania, 2 Calabria, 1 Sardinia. 

- The Case-Fatality Rate in WNND cases was 14.4% (it was 20% in 2018 and 14% in 2024. 

-- This season 10 confirmed Usutu virus human infections have been recorded: 2 in Piedmont, 3 Lombardy, 2 Veneto, 3 Latium.

(...)

Source: High Institute of Health, https://www.epicentro.iss.it/westnile/bollettino/Bollettino_WND_2025_12.pdf

____

#Italy, Integrated #WNV & #USUV #Surveillance - Weekly Bulletin No. 11, September 25 '25 (ISS, Summary)

 

{Summary}

-- During current surveillance week (from 18 to 24 Sept. '25), 33 new confirmed human cases of West Nile Virus have been detected. 

-- Since the beginning of the epidemic season, there have been 680 cases in total, (they were 647 last week); of these: 

- 321 were West Nile Neuroinvasive Disease (WNND): 15 in Piedmont, 44 Lombardy, 27 Veneto, 2 Friuli-Venezia Giulia, 1 Liguria, 25 Emilia-Romagna, 8 Tuscany, 1 Marche, 83 Latium, 2 Molise, 79 Campania, 2 Apulia, 2 Basilicata, 5 Calabria, 1 Sicily, 24 Sardinia), 

- 54 were asymptomatic cases in blood donors, 

- 296 were West Nile Fever cases (1 imported from Kenya, 1 Egypt and 1 Maldives), 

- 3 asymptomatic cases,  

- 6 unspecified cases. 

-- Among confirmed cases, there were 48 deaths: 7 in Piedmont, 5 Lombardy, 2 Emilia-Romagna, 17 Latium, 14 Campania, 2 Calabria, 1 Sardinia. 

- The Case-Fatality Rate among WNND cases was 14.9% (it was 20% in 2018 and 14% in 2024). 

-- During current surveillance week, nine new confirmed human cases of Usutu virus have been confirmed: 2 in Piedmont, 2 Lombardy, 2 Veneto, 3 Latium).

(...)

Source: High Institute of Health, https://www.epicentro.iss.it/westnile/bollettino/Bollettino_WND_2025_11.pdf

____

#Italy, Integrated #Surveillance for #WNV & #USUV - Weekly Bulletin No. 10, 18 September '25 (Summary)

 

{Summary}

-- During current epidemiological week (11– 17 September 2025), 65 new confirmed human cases of infection with West Nile Virus have been reported. 

-- The total number of confirmed cases, since the beginning of the epidemic season, has thus risen to 647 (it was 582 last week), of these: 

- 300 were West Nile Neuroinvasive Disease (WNND): 15 in Piedmont, 39 Lombardy, 24 Veneto, 2 Friuli-Venezia Giulia, 1 Liguria, 23 Emilia-Romagna, 5 Tuscany, 83 Latium, 2 Molise, 77 Campania, 2 Apulia, 2 Basilicata, 5 Calabria, 1 Sicily, 19 Sardinia, 

- 54 were asymptomatic cases detected among blood donors, 

- 284 were West Nile Fever cases (one imported from Kenya), 

- 3 asymptomatic cases and 

- 6 unspecified casese. 

-- Among confirmed cases, there were 47 death cases: 7 in Piedmont, 5 Lombardy, 1 Emilia-Romagna, 16 Latium, 15 Campania, 2 Calabria, 1 Sardinia. 

- The Case-Fatality Rate in WNND cases was 15.8% (it was 20% in 2018 and  14% in 2024). 

-- This week nine confirmed cases of Usutu Virus infection have been reported: 2 in Piedmont, 2 Lombardy, 2 Veneto, 3 Latium.

(...)

Source: High Institute of Health, https://www.epicentro.iss.it/westnile/bollettino/Bollettino_WND_2025_10.pdf

____