#Hemagglutinin and #neuraminidase #antibodies are induced in an #age- and subtype- dependent manner after #influenza virus infection (J Virol., abstract)

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

Hemagglutinin and neuraminidase antibodies are induced in an age- and subtype- dependent manner after influenza virus infection.

Sook-San Wong, Ben Waite, Jacqui Ralston, Tim Wood, G Edwin Reynolds, Ruth Seeds, E. Claire Newbern, Mark G. Thompson, Q. Sue Huang, Richard J. Webby, the SHIVERS Investigation Team

DOI: 10.1128/JVI.01385-19

 

ABSTRACT

Despite evidence that antibodies targeting the influenza virus neuraminidase (NA) protein can be protective and are broadly cross-reactive, the immune response to NA during infection is poorly understood compared to the response to hemagglutinin (HA) protein. As such, we compared the antibody profile to HA and NA in two naturally-infected human cohorts in Auckland, New Zealand; a serosurvey cohort, consisting of pre- and post-influenza season sera from PCR-confirmed influenza cases (n=50), and an immunology cohort, consisting of paired sera collected after PCR-confirmation of infection (n=94). The induction of both HA and NA-antibodies in these cohorts was influenced by age and subtype. Seroconversion to HA was more frequent in those < 20 years old (yo) for influenza A (Serosurvey, p=0.01, Immunology, p=0.02), but not influenza B virus infection. Seroconversion to NA was not influenced by age or virus type. Adults ≥ 20 yo infected with influenza A viruses were more likely to show NA-only seroconversion compared to children (56% vs 14% [5 – 19 yo] and 0% [0 – 4 yo] respectively). Conversely, children infected with influenza B viruses were more likely than adults to show NA-only seroconversion (88% [0 – 4 yo] and 75% [5 – 19 yo] vs 40% [ ≥ 20 yo]). These data indicate a potential role for immunological memory in the dynamics of HA and NA-antibody responses. A better mechanistic understanding of this phenomenon will be critical for any future vaccines aimed at eliciting NA immunity.

 

IMPORTANCE

Data on the immunologic responses to neuraminidase (NA) is lacking when compared to what is available on hemagglutinin (HA) responses, despite growing evidence that NA-immunity can be protective and broadly cross-reactive. Understanding these NA responses during natural infection is key to exploiting these properties for improving influenza vaccines. Using two community-acquired influenza cohorts, we showed that the induction of both HA and NA-antibody after infection is influenced by age and subtypes. Such response dynamics suggests the influence of immunological memory and understanding how this process is regulated will be critical to any vaccine effort targeting NA-immunity.

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

Keywords: Seasonal Influenza; Serology; Seroprevalence.

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#Serological #Evidence of #Yersiniosis, #TBE, #WNV, #Hepatitis E, #CCHF, Lyme #Borreliosis, and #Brucellosis in Febrile Patients Presenting at Diverse Hospitals in #Kenya (Vector Borne Zoo Dis., abstract)

[Source: Vector-Borne and Zoonotic Diseases, full page: (LINK). Abstract, edited.]

Serological Evidence of Yersiniosis, Tick-Borne Encephalitis, West Nile, Hepatitis E, Crimean-Congo Hemorrhagic Fever, Lyme Borreliosis, and Brucellosis in Febrile Patients Presenting at Diverse Hospitals in Kenya

Josphat Nyataya, Moureen Maraka, Allan Lemtudo, Clement Masakhwe, Beth Mutai, Kariuki Njaanake, Benson B. Estambale, Nancy Nyakoe, Joram Siangla, and John Njenga Waitumbi

Published Online: 13 Jan 2020 / DOI: https://doi.org/10.1089/vbz.2019.2484

 

Abstract

Data on pathogen prevalence is crucial for informing exposure and disease risk. We evaluated serological evidence of tick-borne encephalitis (TBE), West Nile (WN), Hepatitis E virus (HEV), Crimean-Congo Hemorrhagic Fever (CCHF), Yersiniosis, Lyme Disease (LD), and brucellosis in 1033 patients presenting with acute febrile illness at 9 health care facilities from diverse ecological zones of Kenya: arid and semiarid (Garissa District Hospital, Lodwar District Hospital, Marigat District Hospital, Gilgil District Hospital), Lake Victoria basin (Kisumu District Hospital, Alupe District Hospital, Kombewa Sub-County Hospital), Kisii highland (Kisii District Hospital), and coastal (Malindi District Hospital). Epidemiological information of the patients such as geography, age, gender, and keeping animals were analyzed as potential risk factors. Of the 1033 samples, 619 (59.9%) were seropositive to at least one pathogen by IgM (current exposure), IgG/IgM (recent exposure), and IgG (past exposure). Collective seroprevalence for current, recent, and past to the pathogens was 9.4%, 5.1%, and 21.1% for LD; 3.6%, 0.5%, and 12.4% for WN; 0.9%, 0.5%, and 16.9% for HEV; 5.8%, 1.3%, and 3.9% for brucellosis; 5.7%, 0.2%, and 2.3% for yersiniosis; 1.7%, 0%, and 6.2% for TBE; and 0.4%, 0%, and 1.9% for CCHF. Brucellosis risk was higher in patients recruited at Garissa District Hospital (odds ratio [OR] = 3.41), HEV (OR = 2.45) and CCHF (OR = 5.46) in Lodwar District Hospital, LD in Alupe District Hospital (OR = 5.73), Kombewa Sub-district hospital (OR = 8.17), and Malindi District hospital (OR = 3.3). Exposure to LD was highest in the younger age group, whereas yersiniosis did not vary with age. Age was a significant risk for WN, brucellosis, CCHF, TBE, and HEV and in those aged >14 years there was an increased risk to WN (OR = 2.30, p < 0.0001), brucellosis (OR = 1.84, p = 0.005), CCHF (OR = 4.35, p = 0.001), TBE (OR = 2.78, p < 0.0001), and HEV (OR = 1.94, p = 0.0001). We conclude that LD is pervasive and constitutes a significant health burden to the study population, whereas yersiniosis and CCHF are not significant threats. Going forward, community-based studies will be needed to capture the true seroprevalence rates and the associated risk factors.

Keywords: Arbovirus; WNV; CCHF; Borreliosis; TBE; Brucellosis; Seroprevalence; Kenya.

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Middle East respiratory syndrome #coronavirus (#MERS-CoV) neutralising #antibodies in a high-risk #human #population, #Morocco, November 2017 to January 2018 (Euro Surveill., abstract)

[Source: Eurosurveillance, full page: (LINK). Abstract, edited.]

Middle East respiratory syndrome coronavirus (MERS-CoV) neutralising antibodies in a high-risk human population, Morocco, November 2017 to January 2018

Anass Abbad 1,2,7, Ranawaka APM Perera 3,7, Latifa Anga 1, Abdellah Faouzi 1, Nhu Nguyen Tran Minh 4, Sk Md Mamunur Rahman Malik 4, Nadia Iounes 2, Abderrahmane Maaroufi 1, Maria D Van Kerkhove 5, Malik Peiris 3,6, Jalal Nourlil 1

Affiliations: 1 Medical Virology and BSL-3 Laboratory, Institut Pasteur du Maroc, Casablanca, Morocco; 2 Laboratoire d’Ecologie et d’Environnement, Faculté des Sciences Ben M’Sik, Université Hassan II, Casablanca, Morocco; 3 School of Public Health, University of Hong-Kong, Hong Kong SAR, China; 4 Health Emergencies Programme, World Health Organization, Regional Office for the Eastern Mediterranean, Cairo, Egypt; 5 Health Emergencies Programme, World Health Organization, Geneva, Switzerland; 6 HKU-Pasteur Research Pole, University of Hong Kong, Hong Kong SAR, China; 7 These authors contributed equally to this work

Correspondence:  Malik Peiris  ; Jalal Nourlil

Citation style for this article: Abbad Anass, Perera Ranawaka APM, Anga Latifa, Faouzi Abdellah, Minh Nhu Nguyen Tran, Malik Sk Md Mamunur Rahman, Iounes Nadia, Maaroufi Abderrahmane, Van Kerkhove Maria D, Peiris Malik, Nourlil Jalal. Middle East respiratory syndrome coronavirus (MERS-CoV) neutralising antibodies in a high-risk human population, Morocco, November 2017 to January 2018. Euro Surveill. 2019;24(48):pii=1900244. https://doi.org/10.2807/1560-7917.ES.2019.24.48.1900244

Received: 14 Apr 2019;   Accepted: 06 Oct 2019

 

Abstract

Background

Middle East respiratory syndrome coronavirus (MERS-CoV) remains a major concern for global public health. Dromedaries are the source of human zoonotic infection. MERS-CoV is enzootic among dromedaries on the Arabian Peninsula, the Middle East and in Africa. Over 70% of infected dromedaries are found in Africa. However, all known zoonotic cases of MERS have occurred in the Arabian Peninsula with none being reported in Africa.

Aim

We aimed to investigate serological evidence of MERS-CoV infection in humans living in camel-herding areas in Morocco to provide insights on whether zoonotic transmission is taking place.

Methods

We carried out a cross sectional seroprevalence study from November 2017 through January 2018. We adapted a generic World Health Organization MERS-CoV questionnaire and protocol to assess demographic and risk factors of infection among a presumed high-risk population. ELISA, MERS-CoV spike pseudoparticle neutralisation tests (ppNT) and plaque neutralisation tests (PRNT) were used to assess MERS-CoV seropositivity.

Results

Serum samples were collected from camel slaughterhouse workers (n = 137), camel herders (n = 156) and individuals of the general population without occupational contact with camels but living in camel herding areas (n = 186). MERS-CoV neutralising antibodies with ≥ 90% reduction of plaque numbers were detected in two (1.5%) slaughterhouse workers, none of the camel herders and one individual from the general population (0.5%).

Conclusions

This study provides evidence of zoonotic transmission of MERS-CoV in Morocco in people who have direct or indirect exposure to dromedary camels.

©  This work is licensed under a Creative Commons Attribution 4.0 International License.

Keywords: MERS-CoV; Human; Serology; Seroprevalence; Morocco.

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#Seroprevalance of #antibodies specific for #SFTS virus and the discovery of #asymptomatic #infections in #Henan Province, #China (PLOS Negl Trop Dis., abstract)

[Source: PLOS Neglected Tropical Diseases, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Seroprevalance of antibodies specific for severe fever with thrombocytopenia syndrome virus and the discovery of asymptomatic infections in Henan Province, China

Yanhua Du , Ningning Cheng , Yi Li, Haifeng Wang, Aiguo You, Jia Su, Yifei Nie, Hongxia Ma, Bianli Xu , Xueyong Huang

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Published: November 25, 2019 / DOI: https://doi.org/10.1371/journal.pntd.0007242 / This is an uncorrected proof.

 

Abstract

Background

Severe fever with thrombocytopenia syndrome (SFTS) is a severe emerging disease caused by SFTS virus (SFTSV), and the geographical distribution of SFTS has been increasing throughout China in recent years. To assess SFTSV-specific antibody seroprevalence, a cross-sectional study was conducted for healthy people in high SFTS endemic areas of Henan province in 2016.

Methods

This study used a stratified random sampling method to select 14 natural villages as the investigation sites. From April to May 2016, participants completed a questionnaire survey and serum samples were collected. All serum samples were subjected to ELISA to detect SFTSV-specific IgM and IgG. All IgM-positive samples were further tested by real-time RT-PCR, and isolation of virus from serum was attempted. Any participant who was IgM-positive was followed up with a month later to confirm health status.

Results

In total, 1463 healthy people participated in this study. The average seropositive rates for SFTSV-specific IgG and IgM were 10.46% (153/1463) and 0.82% (12/1463), respectively. IgM was detected in 12 individuals, and SFTSV RNA was detected in six of them. Virus was isolated from five of the six SFTSV RNA-positive individuals, and phylogenetic analyses revealed that all five isolates belonged to SFTSV group A. No IgM-positive participants exhibited any symptoms or other signs of illness at the one-month follow up.

Conclusions

This study identified a relatively high incidence of SFTSV-specific antibody seropositivity in healthy people in Xinyang city. Moreover, our data provide the first evidence for asymptomatic SFTSV infections, which may have significant implications for SFTS outbreak control.

 

Author summary

Severe fever with thrombocytopenia syndrome (SFTS) is a severe emerging infectious disease caused by SFTS virus (SFTSV) that was first discovered in rural areas of China. Henan province has had the largest number of SFTS cases in China every year since the disease was discovered, however, seropositivity for SFTSV-specific antibodies in healthy people in this region is still not clear. To address this issue, a cross-sectional survey was performed in high endemic areas from April to May 2016. The results showed that SFTSV seroprevalence was relatively high and possibly increasing. Notably, SFTSV RNA, as well as virus itself, was isolated from specimens obtained from healthy people. This study confirmed there are asymptomatic SFTSV infections in humans, and it is the first to report SFTSV isolation from healthy people.

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Citation: Du Y, Cheng N, Li Y, Wang H, You A, Su J, et al. (2019) Seroprevalance of antibodies specific for severe fever with thrombocytopenia syndrome virus and the discovery of asymptomatic infections in Henan Province, China. PLoS Negl Trop Dis 13(11): e0007242. https://doi.org/10.1371/journal.pntd.0007242

Editor: Abdallah M. Samy, Faculty of Science, Ain Shams University (ASU), EGYPT

Received: February 10, 2019; Accepted: October 4, 2019; Published: November 25, 2019

Copyright: © 2019 Du et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the manuscript and its Supporting Information files.

Funding: H.X.Y received grants from the National Natural Science Foundation of China (NO 81573204 https://isisn.nsfc.gov.cn/egrantweb/) and Henan provincial medical science and technology program (grant no.2018010029) .X.B.L. recieved a grant from the National Natural Science Foundation of China (NO 81773500 https://isisn.nsfc.gov.cn/egrantweb/).D.Y.H received a grant from Henan provincial medical science and technology program (grant no.2018020510). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Serology; Seroprevalence; SFTS; Henan; China.

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#Serological prevalence of #avian #H9N2 #influenza virus in #dogs by hemagglutination inhibition assay in Kerman, southeast of #Iran (Vet Res Forum, abstract)

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

Vet Res Forum. 2019 Summer;10(3):249-253. doi: 10.30466/vrf.2018.87879.2140. Epub 2019 Sep 15.

Serological prevalence of avian H9N2 influenza virus in dogs by hemagglutination inhibition assay in Kerman, southeast of Iran.

Saberi M1, Tavakkoli H1, Najmaddini A2, Rezaei M1.

Author information: 1 Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran. 2 DVM Graduate,Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran.

 

Abstract

Influenza is a highly contagious zoonotic disease in the world. Avian H9N2 influenza virus is a significant pandemic pathogen widely distributed throughout the world. Pet ownership has been documented as a risk factor for infection transmission to human. Considering major public health concern, the prevalence of antibodies against avian H9N2 influenza virus was evaluated in 170 serum samples of dogs by hemagglutination inhibition assay. This study is the first survey to assess the epidemiology of avian H9N2 influenza virus infection in dogs in Kerman, southeast of Iran. Out of 170 samples, 65 (38.23%) were positive for H9N2. Antibodies were higher in farm dogs that were kept with other animals and also in dogs were fed a raw diet. These findings emphasize the importance of close attention to these populations for control and prevention programs. It is important to reduce infection burden, especially in regions with widespread distribution of H9N2.

© 2019 Urmia University. All rights reserved.

KEYWORDS: Avian H9N2 influenza virus; Dog; Hemagglutination inhibition; Iran; Seroprevalence

PMID: 31737235 PMCID: PMC6828164 DOI: 10.30466/vrf.2018.87879.2140

Keywords: Avian Influenza; H9N2; Serology; Seroprevalence; Dogs; Iran.

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#ZIKA VIRUS #SEROPREVALENCE IN #BLOOD #DONORS FROM THE NORTHEASTERN REGION OF SÃO PAULO STATE, #BRAZIL, BETWEEN 2015 – 2017 (J Infect., abstract)

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

J Infect. 2019 Nov 15. pii: S0163-4453(19)30296-8. doi: 10.1016/j.jinf.2019.10.002. [Epub ahead of print]

ZIKA VIRUS SEROPREVALENCE IN BLOOD DONORS FROM THE NORTHEASTERN REGION OF SÃO PAULO STATE, BRAZIL, BETWEEN 2015 – 2017.

Slavov SN1, Guaragna Machado RR2, Ferreira AR3, Soares CP2, Araujo DB2, Leal Oliveira DB2, Covas DT3, Durigon EL2, Kashima S3.

Author information: 1 Laboratory of Molecular Biology, Blood Center of Ribeirao Preto, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, 14051-140, Ribeirao Preto, Sao Paulo, Brazil; Department of Internal Medicine, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, 14049-900, Ribeirao Preto, Sao Paulo, Brazil. Electronic address: svetoslav.slavov@hemocentro.fmrp.usp.br. 2 Laboratory of Clinical and Molecular Virology, Institute of Biomedical Sciences, University of Sao Paulo, 05508-000, Sao Paulo, Sao Paulo, Brazil. 3 Laboratory of Molecular Biology, Blood Center of Ribeirao Preto, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, 14051-140, Ribeirao Preto, Sao Paulo, Brazil.

 

Abstract

OBJECTIVES:

Although primarily transmitted by Aedes aegypti mosquitos, Zika virus (ZIKV) can also be transmitted by blood transfusion, due to the fact that some of the infected donors can establish asymptomatic viremia. ZIKV seroprevalence in Brazilian blood donors is unknown. The main reason for this gap in the knowledge originates from the difficulty in evaluating ZIKV humoral immunity due to antigenic cross-reactivity between the different Brazilian flaviviruses and, in particular, dengue virus (DENV). The objective of this study was to evaluate the anti-ZIKV IgG prevalence in blood donors from the Northeast region of the São Paulo State, Brazil, which experienced a ZIKV outbreak in 2016.

METHODS:

We evaluated the ZIKV seroprevalence using the NS1 anti-ZIKV IgG test (Euroimmun), followed by confirmation of the positive and borderline results using the Plaque Reduction Neutralization Test (PRNT). ZIKV seroprevalence was estimated by testing plasma samples collected in 2015 (before the ZIKV outbreak), 2016 (during the outbreak) and 2017 (after the outbreak). In order to investigate possible antigenic cross – reactivity between ZIKV and DENV we also included samples that were taken well before the ZIKV outbreak, in years 2010 and 2013.

RESULTS:

The results obtained by the Euroimmun anti-ZIKV IgG test demonstrated ZIKV seroreactivity in 2015, 2016, and 2017 with prevalences of 5.3%, 12.8% and 13.2%, respectively. The inclusion of blood donor samples from 2010 and 2013, demonstrated anti-ZIKV IgG reactivity only for 2013 (1.7%). The PRNT testing of the ZIKV positive and borderline ELISA reacting samples generated positive results only for the years of 2016 and 2017 (prevalences of 5.6% and 9.1%) which coincided with the introduction of ZIKV in our region.

CONCLUSIONS:

Our results estimate for the first time the ZIKV seroprevalence among Brazilian blood donors from a region with apparently extensive ZIKV circulation and which, at the same time, is highly endemic for DENV. We detected relatively low ZIKV seroprevalence in blood donors from the studied region probably due to the lower intensity of the outbreak compared to other Brazilian locations. Our study adds to the global understanding of ZIKV circulation and the herd immunity of the exposed population.

Copyright © 2019 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

KEYWORDS: Blood donors; Brazil; PRNT; Seroprevalence; Zika virus

PMID: 31738944 DOI: 10.1016/j.jinf.2019.10.002

Keywords: Zika Virus; Serology; Seroprevalence; Blood safety; Brazil.

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#Seroprevalence and #risk factors of #avian #influenza #H9 virus among #poultry #professionals in #Rawalpindi, #Pakistan (J Infect Public Health, abstract)

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

J Infect Public Health. 2019 Jul – Aug;12(4):482-485. doi: 10.1016/j.jiph.2018.11.009. Epub 2018 Dec 18.

Seroprevalence and risk factors of avian influenza H9 virus among poultry professionals in Rawalpindi, Pakistan.

Tahir MF1, Abbas MA2, Ghafoor T3, Dil S4, Shahid MA5, Bullo MMH6, Ain QU7, Ranjha MA8, Khan MA9, Naseem MT10.

Author information: 1 Poultry Research Institute, Rawalpindi, Punjab, Pakistan; Field Epidemiology and Laboratory Training Program, Islamabad, Pakistan. Electronic address: drmftahir@gmail.com. 2 National Agricultural Research Centre, Islamabad, Pakistan. 3 Field Epidemiology and Laboratory Training Program, Islamabad, Pakistan. 4 Field Epidemiology and Laboratory Training Program, Islamabad, Pakistan; Livestock and Dairy Development Department, Punjab, Pakistan. 5 Department of Pathobiology, Faculty of Veterinary Science, Bahauddin Zakariya University, Multan, Pakistan. 6 Field Epidemiology and Laboratory Training Program, Islamabad, Pakistan; Federal General Hospital, Islamabad, Pakistan. 7 Field Epidemiology and Laboratory Training Program, Islamabad, Pakistan; Veterinary Research Institute, Quetta, Balochistan, Pakistan. 8 National Institute of Health, Islamabad, Pakistan. 9 Field Epidemiology and Laboratory Training Program, Islamabad, Pakistan; National Institute of Health, Islamabad, Pakistan. 10 Poultry Research Institute, Rawalpindi, Punjab, Pakistan.

 

Abstract

BACKGROUND:

Avian influenza H9 is endemic in commercial and backyard poultry in Pakistan and is a serious occupational health hazard to industry workers. This study aimed to determine the seroprevalence of avian influenza H9 infection in people working with poultry in Rawalpindi, Pakistan and assess the measures they took to protect themselves from infection.

METHODS:

A cross-sectional study was conducted from December 2016 to May 2017 of 419 people working with poultry in Rawalpindi Division, including farm workers, vaccinators, field veterinarians, butchers and staff working in diagnostic laboratories. Potential participants were randomly approached and gave written consent to participate. Data were collected using a standardized questionnaire and serum samples were processed to detect H9 antibodies using the haemagglutination inhibition test.

RESULTS:

Of the 419 participants, 406 (96.9%) were male. The mean age of the participants was 36.4 (SD 10.86) years. A total of 332 participants agreed to a blood test, 167 of whom were positive for A(H9) antibodies, giving an overall seroprevalence of 50.3%. Laboratory staff had the highest seroprevalence (100%) and veterinarians the lowest (38.5%). Vaccinators, butchers and farm workers had a seroprevalence of 83.3%, 52.4% and 45.5% respectively. Personals who used facemasks had significantly lower (P<0.002) seroprevalence (29.6%) than those who never used them (90.6%). Similarly, those who always used gloves and washed their hands with soap had a seroprevalence of 32.8% compared with 89.0% in those who never took these precautions. Of the participants who handled antigens, 92.3% were seropositive.

CONCLUSION:

Laboratory staff and vaccinators are exposed to viral cultures and influenza vaccines respectively which may explain their high seroprevalence.

Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

KEYWORDS: Avian influenza; Pakistan; Poultry; Seroprevalence

PMID: 30578143 DOI: 10.1016/j.jiph.2018.11.009 [Indexed for MEDLINE] Free full text

Keywords: Avian Influenza; H9N2; Human; Serology; Seroprevalence; Pakistan.

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