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Showing posts with the label human

Safety, tolerability, and immunogenicity of INO-4500, a synthetic #DNA-based #vaccine against #Lassa virus, in a phase 1b clinical trial in healthy Ghanaian adults

  Abstract Background :  Lassa fever (LF) is an acute viral hemorrhagic illness endemic to West Africa, with no licensed vaccines or targeted treatments available, highlighting a critical gap in global health preparedness. T cell-mediated immunity plays a central role in viral control and survival. Synthetic DNA vaccines offer a promising strategy to induce both humoral and cellular immunity against LF. Methods :  A Phase 1b, randomized, double-blind, placebo-controlled trial was conducted to assess the safety, tolerability, and immunogenicity of INO-4500 , a DNA vaccine encoding the Lassa virus (Josiah strain) glycoprotein precursor (GPC). A total of 220 healthy adults were randomized to receive either 1 mg or 2 mg of INO-4500 (intervention), or placebo, administered intradermally (ID) followed by electroporation (EP) at Day 0 and Week 4. Safety was evaluated through Week 48. Primary immunogenicity endpoints included humoral and cellular immune responses at multiple time...

Long-term consequences of #monkeypox virus #infection or modified vaccinia virus Ankara #vaccination in #Belgium ...

  Summary Background Given the continued global circulation of monkeypox virus (MPXV), we aimed to assess the long-term clinical consequences of MPXV infection and the continued presence of the virus in saliva, semen, and the anorectum . We also aimed to compare long-term antibody dynamics after MPXV infection with modified vaccinia Ankara–Bavarian Nordic (MVA-BN) vaccination. Methods In this mixed retrospective and prospective cohort study, adults with acute MPXV infection at the Institute of Tropical Medicine (Antwerp, Belgium) were enrolled in a clinical registry (MPX-COHORT) from May 13, 2022, with follow-up at 1 month after infection. On Oct 3, 2022, we initiated a long-term follow-up study (POQS-FU-PLUS) to extend follow-up of people with mpox and to establish a parallel cohort of adults who received MVA-BN vaccination between Aug 3, 2022, and Jan 4, 2023. Participants were eligible for the second cohort if they received two doses of MVA-BN, unless they had previous smallpox ...

An #intranasal adjuvanted, recombinant #influenza A/ #H5 #vaccine primes against diverse #H5N1 clades: a phase I trial

  Abstract Mucosal influenza vaccines may provide improved protection against infection and transmission , but their development is hindered by absence of immune correlates of protection . Here, we report a randomized, controlled phase I trial of a recombinant influenza A/H5 (A/Indonesia/05/2005, clade 2.1) hemagglutinin vaccine formulated with a nanoemulsion adjuvant (W805EC). The vaccine is administered intranasally in two doses 28 days apart at three antigen levels. Controls receive unadjuvanted H5 or placebo. Six months later, participants receive an intramuscular boost with unadjuvanted inactivated A/H5N1 (A/Vietnam/1203/2004, clade 1) vaccine. Primary outcomes are solicited and unsolicited adverse events (AEs), laboratory safety abnormalities, medically-attended AEs, potential immune-mediated conditions, new-onset chronic conditions, and serious AEs. All vaccines are well tolerated. After the intranasal series, hemagglutination inhibition and microneutralization responses are...

Rift Valley #fever [#RVFV] - #Mauritania and #Senegal (#WHO, D.O.N., Nov. 6 '25)

  Situation at a glance Between 20 September and 30 October 2025, a total of 404 confirmed human cases of Rift Valley fever (RVF), including 42 deaths , were reported by national health authorities in two West African countries : Mauritania and Senegal .  RVF is a zoonotic disease , which mainly affects animals, but can also infect humans.  The majority of human infections result from contact with the blood or organs of infected animals, but human infections have also resulted from the bites of infected mosquitoes .  To date, no human-to-human transmission of RVF has been documented.  While RVF often leads to severe illness in animals, its impact in humans varies, ranging from mild flu-like symptoms to severe hemorrhagic fever that can be fatal .  RVF is endemic in both countries, where recurrent outbreaks have been previously reported in both livestock and humans.  The risk of further spread remains high , especially with environmental conditions favo...

Controlled #human #influenza #infection reveals heterogeneous expulsion of infectious virus into #air

  Abstract Influenza virus is transmitted via respiratory expulsions, but detection of infectious virus in such expulsions has been challenging . Here, we describe quantification and genotyping of infectious virus in respiratory particles using a Modular Influenza Sampling Tunnel (MIST). The particles deposit on cell monolayers , enabling culture, quantification, and sequencing of viruses. Concomitantly, water-sensitive paper and fine particle samplers yield respiratory particle counts over a broad size range. Using the MIST, we captured infectious virus from humans experimentally infected with influenza virus on multiple days post-inoculation . The recovered respiratory particles varied in quantity over three orders of magnitude and contained viral genetic variation that was also detected in samples from infected individuals. Expulsion of infectious virus was associated with infectious viral load in saliva and nasopharyngeal swabs and with clinical symptoms . These data reveal the...

#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 diseas...

A #cattle-derived #human #H5N1 isolate suppresses innate #immunity despite efficient #replication in human respiratory #organoids

  Abstract The H5N1 high pathogenicity avian influenza virus (HPAIV) of clade 2.3.4.4b, which spreads globally via wild birds , has become a major public health concern because it can infect a variety of mammals , including humans . In 2024, infection of dairy cattle with H5N1 HPAIV clade 2.3.4.4b was confirmed in the United States , and subsequent human cases were reported. Although these viruses are highly pathogenic in animal models , human infections have generally been mild , revealing a striking discrepancy . Here, we characterized the cattle-derived human H5N1 isolate A/Texas/37/2024 (TX37-H5N1) using three-dimensional human respiratory organoids derived from induced pluripotent stem (iPS) cells. Despite efficient replication , TX37-H5N1 induced minimal interferon and inflammatory cytokine responses . Bulk and single-cell RNA sequencing revealed reduced STAT1-mediated transcriptional activity in TX37-H5N1-infected organoids compared to the historic H5N1 human isolate A/Vietn...

#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 ...

#Asymptomatic #Human #Infections With Avian #Influenza #H5N1 Virus Confirmed by Molecular and Serologic Testing - A Scoping Review

  Key Points -- Question :  Have asymptomatic infections with highly pathogenic avian influenza A(H5N1) virus been reported in humans? -- Findings:  This scoping review of published reports through August 25, 2025, identified 10 reports of 18 cases of asymptomatic infection with A( H5N1 ) virus, including 2 cases with molecular and serologic confirmation and 16 cases with molecular confirmation alone. Symptom ascertainment methods varied among reported cases. -- Meaning:   Asymptomatic human avian influenza A(H5N1) virus infections have been infrequently reported , with most lacking serologic confirmation; prospective surveillance studies with serial respiratory and serum sampling and detailed symptom monitoring for persons with high-risk exposures could provide data to inform future public health responses. Abstract Importance    Since 1997, more than 1000 infections with highly pathogenic avian influenza A(H5N1) virus among humans have been reported globa...

Joint #FAO / #WHO / #WOAH Rapid #Risk #Assessment of Rift Valley fever (#RVF) in #Senegal and #Mauritania: Implications for Public Health and Animal Health (Oct. 24 '25)

  {Excerpt} Risk statement This risk assessment is based on the current epidemiological and epizootic situation of Rift Valley fever (RVF) in Senegal and Mauritania , from 20 September through 8 October 2025. The risk assessment was conducted separately for each country . However, the findings indicate that the level of risk is the same for both countries across all levels, for both human and animal health .   During this period , Senegal reported 119 confirmed human RVF cases , including 16 deaths , resulting in a case fatality rate (CFR) of 13.4% . Cases were recorded across eight health districts in three regions of Senegal, with the majority in Saint-Louis Region with 110 cases (92%) followed by Louga (four cases) and Matam (one case).  The affected districts in Saint-Louis Region : Podor, Richard-Toll, Dagana, and Saint-Louis are located along the northern border with Mauritania along the Senegal River.   The most affected age groups were 15- 35 years ...

#Resurgence of Zoonotic Highly Pathogenic Avian #Influenza #H5N1 Virus in #Cambodia

  {Excerpts} To the Editor : After a decade of no reported human cases, Cambodia faces a resurgence of highly pathogenic avian influenza (HPAI) A(H5N1) virus infections , with an overall mortality of 38%. Cases have occurred primarily in children and adolescents who were exposed to infected poultry (...). From February 2023 through August 2024, a total of 16 infections were detected through the long-standing national influenza-like illness and severe acute respiratory infection surveillance systems, both of which were strengthened by expanded laboratory-testing capacity that was developed during the coronavirus disease 2019 pandemic. All 16 patients reported exposure to sick or dead poultry , and outbreak investigations identified contemporary, genetically similar viruses in poultry collected in or around case households or from active, longitudinal surveillance of live-bird markets . Genomic sequencing revealed an avian origin for all the human infections , and sequences have been...

Cross-Species #Transmission #Risks of a #Quail-Origin #H7N9 #Influenza Virus from #China Between Avian and #Mammalian Hosts

  Abstract The H7N9 influenza viruses, which are capable of causing severe respiratory syndrome in humans , were first discovered to infect humans in 2013 and continue to pose a persistent public health threat . Quail has been proposed as a potential intermediate host that may facilitate the emergence of novel reassorted influenza A viruses with the capacity to infect humans across species barriers; however, information on the biological characterization of quail H7N9 remains limited. In this study, we isolated and identified an avian H7N9 influenza virus from quails , designated as A/quail/Hebei/CH06-07/2018 (H7N9) and abbreviated as CH06-07, in Hebei, China . Phylogenetic analyses revealed that both the HA gene and the NA gene of CH06-07 were clustered in the Eurasian lineage . Furthermore, CH06-07 exhibited binding affinity for both α2,3-linked and α2,6-linked sialic acid receptors and demonstrated high pathogenicity in both quails and mice . Notably, transmission studies reveal...

#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....

#Cambodia notified two additional #human cases of infection with #influenza #H5N1, #Bangladesh one case of #H5, #China four cases of #H9N2 (HK CHP, Nov. 21 '25)

{Excerpt} This Week : [Date of report - Country - Province / Region District / City - Sex - Age - Condition at time of reporting  - Subtype of virus] 1) .../10/2025 - Cambodia - Takeo Province - F - 14 - Hospitalised - H5N1  2) 16/10/2025 - Cambodia - Kampong Speu Province - F - 3 - Under intensive care - H5N1 (...) [Place of occurrence - No. of cases  (No. of deaths) - Details] -- Bangladesh - 1(0)  - Avian influenza A(H5) :  1) Sylhet Division : A boy with onset on July 27, 2025.  -- Chinese Mainland - 4(0)  - Avian influenza A( H9N2 ):  - Guangdong Province :  1) An individual with onset in February 2025. The case was retrospectively reported.  - Guangxi Zhuang Autonomous Region :  2, 3) Two individuals with onset in February 2025. Both cases were retrospectively reported.   - Tianjin Municipality :  4) An individual with onset in February 2025. The case was retrospectively reported.  -- Mexico - 1(0)  - ...

Toddler in western #Cambodia becomes 16th #H5N1 bird #flu virus victim in 2025 (Antara)

  {Excerpt} Phnom Penh (ANTARA) - A 3-year-old girl from Kampong Speu Province, western Cambodia, has been confirmed to have contracted H5N1 bird flu , bringing the number of cases to 16 so far this year, the Cambodian Ministry of Health said in a statement on Thursday (16/10) evening local time. Laboratory results from Cambodia's National Institute of Public Health on October 15 showed the girl tested positive for the H5N1 virus, the statement said. The patient had symptoms of fever, diarrhea, cough, and abdominal pain , and is currently undergoing intensive care with a team of doctors, the statement added. The girl is a resident of Chek Village, Basedth District. Investigations found that chickens and ducks had contracted the disease and died at the girl's home and at her neighbor's about a week before she fell ill, the statement said. (...) Source: Antara,  https://www.antaranews.com/berita/5181569/balita-di-kamboja-barat-jadi-korban-flu-burung-ke-16-pada-2025 ____

#Genetic and Serological Analysis of #H7N3 Avian #Influenza Viruses in #Mexico for #Pandemic #Risk Assessment

  Abstract Avian influenza A viruses pose ongoing threats to human and animal health, with H7 subtypes causing outbreaks globally . In Mexico , highly pathogenic H7N3 viruses have circulated in poultry since 2012, causing sporadic human infections . Here we analyzed genetic markers in hemagglutinin sequences from Mexican H7N3 isolates and conducted serological assays on human populations with poultry exposure . Our results show conserved avian-like receptor binding sites , thus limiting human adaptation , alongside antigenic drift and acquisition of glycosylation sites likely driven by vaccination. Serological testing of 1103 individuals revealed no detectable antibodies against H7N3, indicating a naïve population . Phylogenetic analyses revealed multiple virus clades circulating regionally. These findings suggest that while current H7N3 viruses have limited capacity for sustained human transmission, the lack of population immunity underscores the importance of continued surveillan...

#Influenza at the #human - #animal #interface - Summary and #risk #assessment, from 26 August to 29 September 2025 (#WHO, edited)

  New human cases {1,2}:  -- From 26 August to 29 September 2025 , based on reporting date, the detection of influenza A(H5) in one human , influenza A(H5N1) in one human , influenza A(H9N2) in eight humans and an influenza A(H1N1) variant ((H1N1)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}  Risk assessment {5}:  -- Sustained human to human transmission has not been reported from these events.  -- Based on information available at the time of this risk assessment update , the overall public health risk from currently known influenza A viruses d...