Immune escape #adaptive #mutations in the #H7N9 #avian #influenza #hemagglutinin protein increase virus #replication #fitness and decrease #pandemic #potential (J Virol., abstract)

[Source: Journal of Virology, full page: (LINK). Abstract, edited.]

Immune escape adaptive mutations in the H7N9 avian influenza hemagglutinin protein increase virus replication fitness and decrease pandemic potential

Pengxiang Chang, Joshua E. Sealy, Jean-Remy Sadeyen, Sushant Bhat, Deimante Lukosaityte, Yipeng Sun, Munir Iqbal

DOI: 10.1128/JVI.00216-20



H7N9 avian influenza viruses (AIVs) continue to evolve and remain a huge threat to human health and the poultry industry. Previously, serially passaging the H7N9 A/Anhui/1/2013 virus in the presence of homologous ferret antiserum resulted in immune escape viruses containing amino acid substitutions alanine to threonine at residues 125 (A125T), 151 (A151T) and leucine to glutamine at residue 217 (L217Q) in the hemagglutinin (HA) protein. These HA mutations have also been found in the field isolates in 2019. To investigate the potential threat of the serum escape mutant viruses to humans and poultry, the impact of these HA substitutions, either individually or in combination, on receptor binding, pH of fusion, thermal stability and virus replication were investigated. Our results showed the serum escape mutant formed large plaques in Madin-Darby canine kidney (MDCK) cells and grew robustly in vitro and in ovo. They had a lower pH of fusion and increased thermal stability. Of note, the serum escape mutant completely lost the ability to bind to human-like receptor analogues. Further analysis revealed that N-linked glycosylation, as a result of A125T or A151T substitutions in HA, resulted in reduced receptor binding avidity toward both human and avian-like receptor analogues, and the A125T+A151T mutations completely abolished human-like receptor binding. The L217Q mutation enhanced the H7N9 acid and thermal stability while the A151T mutation dramatically decreased H7N9 HA thermal stability. To conclude, H7N9 AIVs that contain A125T+A151T+L217Q mutations in HA protein might pose a reduced pandemic risk but remain a heightened threat for poultry.



Avian influenza H7N9 viruses have been causing disease outbreaks in poultry and humans. We previously determined that propagation of H7N9 virus in the virus-specific antiserum give rise to mutant viruses carrying mutations A125T+A151T+L217Q in their hemagglutinin protein, enabling the virus to overcome vaccine-induced immunity. As predicted, these immune escape mutations were also observed in the field viruses that likely emerged in the immunised or naturally exposed birds. This study demonstrates that the immune escape mutants also (i) gained greater replication ability in cultured cells and in chick embryo as well as (ii) increased acid and thermal stability, but (iii) lost preferences for binding to human-type receptor while maintaining binding for the avian-like receptor. Therefore, they potentially pose reduced pandemic risk. However, the emergent virus variants containing indicated mutations remain a significant risk to the poultry due to antigenic drift and improved fitness for poultry.

Copyright © 2020 Chang et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.

Keywords: Avian Influenza; H7N9; Poultry; Evolution.


Adjuvanted #H5N1 #influenza #vaccine enhances both cross-reactive memory B cell and strain-specific naive B cell responses in humans (Proc Natl Acad Sci USA, abstract)

[Source: Proceedings of the National Academy of Sciences of the United States of America, full page: (LINK). Abstract, edited.]

Adjuvanted H5N1 influenza vaccine enhances both cross-reactive memory B cell and strain-specific naive B cell responses in humans

Ali H. Ellebedy,  Raffael Nachbagauer, Katherine J. L. Jackson, Ya-Nan Dai, Julianna Han, Wafaa B. Alsoussi, Carl W. Davis, Daniel Stadlbauer, Nadine Rouphael, Veronika Chromikova, Megan McCausland, Cathy Y. Chang, Mario Cortese, Mary Bower, Chakravarthy Chennareddy, Aaron J. Schmitz, Veronika I. Zarnitsyna, Lilin Lai, Arvind Rajabhathor, Cheyann Kazemian, Rustom Antia, Mark J. Mulligan,  Andrew B. Ward,  Daved H. Fremont, Scott D. Boyd, Bali Pulendran, Florian Krammer, and Rafi Ahmed

PNAS first published July 13, 2020

Contributed by Rafi Ahmed, November 8, 2019 (sent for review April 19, 2019; reviewed by Robert L. Coffman and Marc K. Jenkins)



The development of a universal influenza vaccine is a major public health need globally, and identifying the optimal formulation will be an important first step for developing such a vaccine. Here we show that a two-dose immunization of humans with an inactivated, AS03-adjuvanted H5N1 avian influenza virus vaccine engaged both the preexisting memory and naive B cell compartments. Importantly, we show that the recruited memory B cells after first immunization were directed against conserved epitopes within the H5 HA stem region while the responses after the second immunization were mostly directed against strain-specific epitopes within the HA globular head. Taken together these findings have broad implications toward optimizing vaccination strategies for developing more effective vaccines against pandemic viruses.



There is a need for improved influenza vaccines. In this study we compared the antibody responses in humans after vaccination with an AS03-adjuvanted versus nonadjuvanted H5N1 avian influenza virus inactivated vaccine. Healthy young adults received two doses of either formulation 3 wk apart. We found that AS03 significantly enhanced H5 hemagglutinin (HA)-specific plasmablast and antibody responses compared to the nonadjuvanted vaccine. Plasmablast response after the first immunization was exclusively directed to the conserved HA stem region and came from memory B cells. Monoclonal antibodies (mAbs) derived from these plasmablasts had high levels of somatic hypermutation (SHM) and recognized the HA stem region of multiple influenza virus subtypes. Second immunization induced a plasmablast response to the highly variable HA head region. mAbs derived from these plasmablasts exhibited minimal SHM (naive B cell origin) and largely recognized the HA head region of the immunizing H5N1 strain. Interestingly, the antibody response to H5 HA stem region was much lower after the second immunization, and this suppression was most likely due to blocking of these epitopes by stem-specific antibodies induced by the first immunization. Taken together, these findings show that an adjuvanted influenza vaccine can substantially increase antibody responses in humans by effectively recruiting preexisting memory B cells as well as naive B cells into the response. In addition, we show that high levels of preexisting antibody can have a negative effect on boosting. These findings have implications toward the development of a universal influenza vaccine.



1 Present address: Division of Immunobiology, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110.

2 Present address: Immunology Division, Garvan Institute of Medical Research, Darlinghurst, NSW 2010, Australia.

3 Present address: Departments of Pathology, and Microbiology & Immunology, Institute for Immunity, Transplantation and Infection, Stanford University, Stanford, CA 94305.

4 Present address: Division of Infectious Diseases and Immunology, Department of Medicine, New York University, New York, NY 10016.

5 To whom correspondence may be addressed. Email:

Author contributions: A.H.E. and R. Ahmed designed research; A.H.E., R.N., Y.-N.D., J.H., W.B.A., D.S., N.R., V.C., M.M., C.Y.C., and C.K. performed research; K.J.L.J., M.C., M.B., C.C., A.J.S., L.L., A.R., M.J.M., A.B.W., D.H.F., S.D.B., B.P., and F.K. contributed new reagents/analytic tools; A.H.E., K.J.L.J., C.W.D., V.I.Z., R. Antia, D.H.F., and S.D.B. analyzed data; and A.H.E. and R. Ahmed wrote the paper.

Reviewers: R.L.C., University of California; and M.K.J., University of Minnesota.

The authors declare no competing interest.

Data deposition: Structures have been deposited in the Electron Microscopy Data Bank (accession codes: 1F03: EMD-20570 1H09: EMD-20571 1C01: EMD-20569) and BioProject Sequence Read Archive (accession no. PRJNA533650).

This article contains supporting information online  at Published under the PNAS license.

Keywords: Avian Influenza; H5N1; Vaccines.


#Human #H9N2 #Avian #Influenza #Infection: #Epidemiological and #Clinical Characterization of 16 Cases in #China (Virol Sin., summary)

[Source: Virologica Sinica, full page: (LINK). Summary, edited.]

Human H9N2 Avian Influenza Infection: Epidemiological and Clinical Characterization of 16 Cases in China

Xuan Dong, Jiasong Xiong, Chaolin Huang, Jie Xiang, Wenjuan Wu, Nanshan Chen, Danning Wen, Chao Tu, Xueli Qiao, Liang Kang, Zhongzi Yao, Dingyu Zhang & Quanjiao Chen

Virologica Sinica (2020)


Dear Editor, The first human infections with avian influenza virus (AIV) H9N2 were  reported in 1998 (Guo et al. 1999). As of October 18th, 2019, 59 cases of human infection  with H9N2 have been reported globally, including 50 cases in China, three in Bangladesh,  four in Egypt, one in Pakistan and one in Oman (World Health  Organization.; Peacock et al. 2019). Among the 59 patients,  three (5.1%) presented with severe pneumonia and 56 had mild influenza-like symptoms  (World Health Organization. In  general, human infections with H9N2 are sporadic and the majority of cases are mild  and non-fatal, and there is no evidence of human-to-human transmission to date  (Peacock et al. 2019).


Keywords: Avian Influenza; Human; H9N2; China.


Genetically and antigenically #divergent #influenza A(#H9N2) viruses exhibit differential #replication and #transmission phenotypes in #mammalian models (J Virol., abstract)

[Source: Journal of Virology, full page: (LINK). Abstract, edited.]

Genetically and antigenically divergent influenza A(H9N2) viruses exhibit differential replication and transmission phenotypes in mammalian models

Jessica A Belser, Xiangjie Sun, Nicole Brock, Claudia Pappas, Joanna A Pulit-Penaloza, Hui Zeng, Yunho Jang, Joyce Jones, Paul J Carney, Jessie Chang, Nguyen Van Long, Nguyen Thi Diep, Sharmi Thor, Han Di, Genyan Yang, Peter W Cook, Hannah M Creager, Dayan Wang, Jeffrey McFarland, Pham Van Dong, David E. Wentworth, Terrence M Tumpey, John R Barnes, James Stevens, C. Todd Davis, Taronna R Maines

DOI: 10.1128/JVI.00451-20



Low pathogenicity avian influenza A(H9N2) viruses, enzootic in poultry populations in Asia, are associated with fewer confirmed human infections but higher rates of seropositivity compared to A(H5) or A(H7) subtype viruses. Co-circulation of A(H5) and A(H7) viruses leads to the generation of reassortant viruses bearing A(H9N2) internal genes with markers of mammalian adaptation, warranting continued surveillance in both avian and human populations. Here, we describe active surveillance efforts in live poultry markets in Vietnam in 2018 and compare representative viruses to G1 and Y280 lineage viruses that have infected humans. Receptor binding properties, pH thresholds for HA activation, in vitro replication in human respiratory tract cells, and in vivo mammalian pathogenicity and transmissibility were investigated. While A(H9N2) viruses from both poultry and humans exhibited features associated with mammalian adaptation, one human isolate from 2018, A/Anhui-Lujiang/39/2018, exhibited increased capacity for replication and transmission, demonstrating the pandemic potential of A(H9N2) viruses.



A(H9N2) influenza viruses are widespread in poultry in many parts of the world, and for over twenty years, have sporadically jumped species barriers to cause human infection. As these viruses continue to diversify genetically and antigenically, it is critical to closely monitor viruses responsible for human infections, to ascertain if A(H9N2) viruses are acquiring properties that make them better suited to infect and spread among humans. In this study, we describe an active poultry surveillance system established in Vietnam to identify the scope of influenza viruses present in live bird markets and the threat they pose to human health. Assessment of a recent A(H9N2) virus isolated from an individual in China in 2018 is also reported and was found to exhibit properties of adaptation to humans and, importantly, show similarities to strains isolated from the live bird markets of Vietnam.

Copyright © 2020 American Society for Microbiology. All Rights Reserved.

Keywords: Avian Influenza; H9N2; Human; Poultry; China; Vietnam.


Prevalent #Eurasian #avian-like #H1N1 #swine #influenza virus with #H1N1pdm09 viral #genes facilitating #human infection (Proc Natl Acad Sci USA, abstract)

[Source: Proceedings of the National Academy of Sciences of the United States of America, full page: (LINK). Abstract, edited.]

Prevalent Eurasian avian-like H1N1 swine influenza virus with 2009 pandemic viral genes facilitating human infection

Honglei Sun, Yihong Xiao,  Jiyu Liu, Dayan Wang, Fangtao Li, Chenxi Wang, Chong Li, Junda Zhu, Jingwei Song, Haoran Sun,  Zhimin Jiang, Litao Liu, Xin Zhang, Kai Wei, Dongjun Hou, Juan Pu, Yipeng Sun, Qi Tong, Yuhai Bi, Kin-Chow Chang, Sidang Liu,  George F. Gao, and Jinhua Liu

PNAS first published June 29, 2020

Contributed by George F. Gao, April 28, 2020 (sent for review December 9, 2019; reviewed by Ian H. Brown and Xiu-Feng Henry Wan)



Pigs are intermediate hosts for the generation of pandemic influenza virus. Thus, systematic surveillance of influenza viruses in pigs is a key measure for prewarning the emergence of the next pandemic influenza. Here, we identified a reassortant EA H1N1 virus possessing pdm/09 and TR-derived internal genes, termed as G4 genotype, which has become predominant in swine populations since 2016. Similar to pdm/09 virus, G4 viruses have all the essential hallmarks of a candidate pandemic virus. Of concern is that swine workers show elevated seroprevalence for G4 virus. Controlling the prevailing G4 EA H1N1 viruses in pigs and close monitoring in human populations, especially the workers in swine industry, should be urgently implemented.



Pigs are considered as important hosts or “mixing vessels” for the generation of pandemic influenza viruses. Systematic surveillance of influenza viruses in pigs is essential for early warning and preparedness for the next potential pandemic. Here, we report on an influenza virus surveillance of pigs from 2011 to 2018 in China, and identify a recently emerged genotype 4 (G4) reassortant Eurasian avian-like (EA) H1N1 virus, which bears 2009 pandemic (pdm/09) and triple-reassortant (TR)-derived internal genes and has been predominant in swine populations since 2016. Similar to pdm/09 virus, G4 viruses bind to human-type receptors, produce much higher progeny virus in human airway epithelial cells, and show efficient infectivity and aerosol transmission in ferrets. Moreover, low antigenic cross-reactivity of human influenza vaccine strains with G4 reassortant EA H1N1 virus indicates that preexisting population immunity does not provide protection against G4 viruses. Further serological surveillance among occupational exposure population showed that 10.4% (35/338) of swine workers were positive for G4 EA H1N1 virus, especially for participants 18 y to 35 y old, who had 20.5% (9/44) seropositive rates, indicating that the predominant G4 EA H1N1 virus has acquired increased human infectivity. Such infectivity greatly enhances the opportunity for virus adaptation in humans and raises concerns for the possible generation of pandemic viruses.

swine influenza – Eurasian avian-like H1N1 virus – 2009 pandemic H1N1 virus – reassortant – pandemic potential



1 H.S., Y.X., and J.L. contributed equally to this work.

2 To whom correspondence may be addressed. Email: or

Author contributions: Honglei Sun, Y.X., S.L., G.F.G., and Jinhua Liu designed research; Honglei Sun, Y.X., Jiyu Liu, F.L., C.L., J.Z., J.S., Haoran Sun, Z.J., L.L., X.Z., K.W., D.H., and Q.T. performed research; Honglei Sun, Jiyu Liu, D.W., C.W., J.P., Y.B., and Jinhua Liu analyzed data; and Honglei Sun, J.P., Y.S., K.-C.C., G.F.G., and Jinhua Liu wrote the paper.

Reviewers: I.H.B., Animal and Plant Health Agency; and X.-F.H.W., University of Missouri.

The authors declare no competing interest.

Data deposition: The sequences generated in this study have been deposited in the GenBank database (accession nos. are listed in SI Appendix, Table S3).

This article contains supporting information online at

Published under the PNAS license.

Keywords: Influenza A; Reassortant strain; Avian Influenza; Swine Influenza; Pigs; Human; China; H1N1; H1N1pdm09.


#Geographical #Variation in the #Risk of #H7N9 #Human #Infections in #China: Implications for Risk-Based #Surveillance (Sci Rep., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Sci Rep. 2020 Jun 25;10(1):10372. doi: 10.1038/s41598-020-66359-1.

Geographical Variation in the Risk of H7N9 Human Infections in China: Implications for Risk-Based Surveillance

Xiaoyan Zhou 1, Lu Gao 2, Youming Wang 2, Yin Li 2 3, Yi Zhang 2, Chaojian Shen 2, Ailing Liu 2, Qi Yu 4, Wenyi Zhang 5, Alexander Pekin 6, Fusheng Guo 7, Carl Smith 8, Archie C A Clements 9 10, John Edwards 6 2 3, Baoxu Huang 11, Ricardo J Soares Magalhães 6 12

Affiliations collapse: 1 School of Veterinary Science, The University of Queensland, Brisbane, Australia. 2 China Animal Health and Epidemiology Centre, Ministry of Agriculture and Rural Affairs, Qingdao, PR China. 3 School of Veterinary and Biomedical Sciences, Murdoch University, Perth, Australia. 4 Beijing Center for Animal Disease Prevention and Control, Beijing, PR China. 5 Institute of Disease Control and Prevention, Academy of Military Medical Science, Beijing, PR China.  6 School of Veterinary Science, The University of Queensland, Brisbane, Australia. 7 Food and Agriculture Organization of the United Nations (FAO), Bangkok, Thailand. 8 School of Business, The University of Queensland, Brisbane, Australia. 9 Faculty of Health Sciences, Curtin University, Perth, Australia. 10 Telethon Kids Institute, Perth, Australia. 11 China Animal Health and Epidemiology Centre, Ministry of Agriculture and Rural Affairs, Qingdao, PR China. 12 Child Health Research Centre, The University of Queensland, Brisbane, Australia.

PMID: 32587266 DOI: 10.1038/s41598-020-66359-1



The influenza A (H7N9) subtype remains a public health problem in China affecting individuals in contact with live poultry, particularly at live bird markets. Despite enhanced surveillance and biosecurity at LBMs H7N9 viruses are now more widespread in China. This study aims to quantify the temporal relationship between poultry surveillance results and the onset of human H7N9 infections during 2013-2017 and to estimate risk factors associated with geographical risk of H7N9 human infections in counties in Southeast China. Our results suggest that poultry surveillance data can potentially be used as early warning indicators for human H7N9 notifications. Furthermore, we found that human H7N9 incidence at county-level was significantly associated with the presence of wholesale LBMs, the density of retail LBMs, the presence of poultry virological positives, poultry movements from high-risk areas, as well as chicken population density and human population density. The results of this study can influence the current AI H7N9 control program by supporting the integration of poultry surveillance data with human H7N9 notifications as an early warning of the timing and areas at risk for human infection. The findings also highlight areas in China where monitoring of poultry movement and poultry infections could be prioritized.

Keywords: Avian Influenza; H7N9; Human; Poultry; China.


#Aerosol #transmission from infected #swine to #ferrets of an #H3N2 virus collected from an #agricultural #fair and associated with #human variant infections (J Virol., abstract)

[Source: Journal of Virology, full page: (LINK). Abstract, edited.]

Aerosol transmission from infected swine to ferrets of an H3N2 virus collected from an agricultural fair and associated with human variant infections

Bryan S. Kaplan, J. Brian Kimble, Jennifer Chang, Tavis K. Anderson, Phillip C. Gauger, Alicia Janas-Martindale, Mary Lea Killian, Andrew S. Bowman, Amy L. Vincent

DOI: 10.1128/JVI.01009-20



Influenza A viruses (IAV) sporadically transmit from swine to humans, typically associated with agricultural fairs in the USA. A human seasonal H3 from the 2010-2011 IAV season was introduced into the US swine population and termed H3.2010.1 to differentiate from the previous swine H3. This H3N2 lineage became widespread in the US commercial swine population, subsequently spilling over into exhibition swine, and caused a majority of H3N2 variant (H3N2v) cases in humans in 2016 and 2017. A cluster of human H3N2v cases were reported at an agricultural fair in Ohio in 2017 where 2010.1 H3N2 IAV was concurrently detected in exhibition swine. Genomic analysis showed the swine and human isolates were nearly identical. Here we evaluated the propensity of a 2010.1 H3N2 IAV (A/swine/Ohio/A01354299/2017; sw/OH/2017) isolated from a pig in the agricultural fair outbreak to replicate in ferrets and transmit from swine to ferret. Sw/OH/2017 displayed robust replication in the ferret respiratory tract, causing slight fever and moderate weight loss. Further, sw/OH/2017 was capable of efficient respiratory droplet transmission from infected pigs to contact ferrets. These findings establish a model for evaluating the propensity of swine IAV to transmit from pig-to-ferret as a measure of risk to the human population. The identification of higher risk swine strains can then be targeted for control measures to limit the dissemination at human-swine interfaces to reduce the risk of zoonotic infections and inform pandemic planning.



A recently emerged lineage of human-like H3N2 (H3.2010.1) influenza A virus (IAV) from swine have been frequently detected in commercial and exhibition swine in recent years and were associated with H3N2 variant cases in humans from 2016 and 2017. To demonstrate a model for characterizing the potential for zoonotic transmission associated with swine IAV, we performed an in vivo transmission study between pigs infected with an H3.2010.1 H3N2 and aerosol contact ferrets. The efficient interspecies transmission demonstrated for the H3.2010.1 IAV-S emphasizes the need for further characterization of viruses circulating at the swine-human interface for transmission potential prior to human spillover and the development and implementation of more robust vaccines and control strategies to mitigate human exposure to higher risk swine strains.

This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.

Keywords: Swine Influenza; Influenza A; H3N2; Reassortant strain; Pigs; Human; USA; Animal models.


#Epidemiological Characteristics of a Case Infected With #Avian #Influenza A (#H5N6) Virus Associated With #Exposure to #Aerosol (Zhonghua Liu Xing Bing Xue Za Zhi, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Zhonghua Liu Xing Bing Xue Za Zhi. 2020 Mar 10;41(3):358-362. doi: 10.3760/cma.j.issn.0254-6450.2020.03.015.

[Epidemiological Characteristics of a Case Infected With Avian Influenza A (H5N6) Virus Associated With Exposure to Aerosol]

[Article in Chinese]

Y H Liu 1, J Y Lu 1, W H Liu 1, Y Ma 1, L Cao 1, K B Li 1, T G Li 1, Z B Zhang 1, Z C Yang 1

Affiliation: 1 Guangzhou Municipal Center for Disease Control and Prevention, Guangzhou 510440, China.

PMID: 32294835 DOI: 10.3760/cma.j.issn.0254-6450.2020.03.015


Abstract  in English , Chinese


To investigate the epidemiological and clinical characteristics of a case infected with avian influenza A (H5N6) virus associated with exposure to aerosol and provide evidence for the prevention and control of human infection with avian influenza virus.


Epidemiological investigation was conducted to identify the history of exposure, infection route, and disease progression. Real-time fluorescent quantitative RT-PCR was used to test the samples collected from the case, close contacts, environment and poultry market.


The case had no history of exposure to live poultry and poultry market. But before the onset the case had a history of exposure to the live poultry placed in a car with doors and windows closed. The samples collected from the case’s lower respiratory tract and the remaining frozen chicken meat were all influenza A (H5N6) virus positive.


The source of infection was the live poultry, and the infection route might be the exposure to aerosol in a car with doors and windows closed, where the poultry were temporarily stored. It is necessary to promote centralized poultry slaughtering, cold chain distribution and fresh poultry sale, as well as strengthen health education and establish the concept of consuming fresh poultry.

Keywords: Aerosol; Epidemiological investigation; Influenza A (H5N6).

Keywords: Avian Influenza; H5N6; Human; Poultry; China.


#Genetic Characterization of the First Detected #Human Case of Low Pathogenic #Avian #Influenza A/ #H9N2 in sub-Saharan Africa, #Senegal (Emerg Microbes Infect., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Emerg Microbes Infect. 2020 Dec;9(1):1092-1095. doi: 10.1080/22221751.2020.1763858.

Genetic Characterization of the First Detected Human Case of Low Pathogenic Avian Influenza A/H9N2 in sub-Saharan Africa, Senegal

Mamadou Malado Jallow 1, Amary Fall 1, Mamadou Aliou Barry 2, Boly Diop 3, Sara Sy 1, Déborah Goudiaby 1, Malick Fall 4, Vincent Enouf 5, Mbayame Ndiaye Niang 1, Ndongo Dia 1

Affiliations: 1 Département de Virologie, Institut Pasteur de Dakar, Dakar, Sénégal.  2 Unité d’Epidémiologie des maladies infectieuses, Institut Pasteur de Dakar, Dakar, Sénégal. 3 Division surveillance épidémiologique et riposte vaccinale du ministère de la Santé et de l’action sociale, Dakar, Senegal. 4 Département de Biologie Animale, Faculté des Sciences et Techniques, Université Cheikh Anta DIOP de Dakar, Dakar, Sénégal. 5 Institut Pasteur Paris, Plateforme P2M, Dakar, Senegal.

PMID: 32471335 DOI: 10.1080/22221751.2020.1763858



The H9N2 influenza virus has become one of the dominant subtypes of influenza virus circulating in poultry, wild birds, and can occasionally cross the mammalian species barrier. Here, we report the first human A/H9N2 in Sub-Saharan Africa. The patient was a child of 16 months’ old living in the South-West of Senegal. He had no influenza vaccination history and no other disease history. He had symptoms of fever with an auxiliary temperature of 39.1°C. Respiratory symptoms were an intense cough, runny nose and pulmonary crackles. All eight genome segments belonged to the A/H9N2 AIV subtype and the strain characyerized as of low pathogenicity with a RSSR/GLF amino acids mo-tif. Phylogenetic analysis of both complete HA and NA gene segments showed that the A/H9N2 subtype virus from Senegal belonged to the G1 lineage. This human case highlights the weakness of influenza surveillance in animals and the need for enhanced surveillance using a one-health approach.

Keywords: A/H9N2; Avian Influenza; Human; Senegal.


#Seroprevalence of #Nipah Virus Infection in Peninsular #Malaysia (J Infect Dis., abstract)

[Source: Journal of Infectious Diseases, full page: (LINK). Abstract, edited.]

Seroprevalence of Nipah Virus Infection in Peninsular Malaysia

Ming-Yen Yong, Soo-Ching Lee, Romano Ngui, Yvonne Ai-Lian Lim, Maude E Phipps, Li-Yen Chang

The Journal of Infectious Diseases, Volume 221, Issue Supplement_4, 1 May 2020, Pages S370–S374,

Published: 11 May 2020



Nipah virus (NiV) outbreak occurred in Malaysia in 1998. The natural host reservoir for NiV is Pteropus bats, which are commonly found throughout Malaysia. Humans become infected when NiV spills over from the reservoir species. In this study, NiV serosurveillance in Peninsular Malaysia, particularly among the indigenous population, was performed. The collected samples were tested for presence of NiV antibodies using a comparative indirect enzyme-linked immunosorbent assay based on the recombinant NiV nucleocapsid (rNiV-N) protein. We found that 10.73% of the participants recruited in this study had antibodies against rNiV-N, suggesting possible exposure to NiV.

Issue Section: supplement articles

© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail:

This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (

Keywords: Nipah virus; Human; Serology; Seroprevalence; Malaysia.