tetano
Editor, Senior Moderator
J Infect Dis. 2014 Oct 29. pii: jiu529. [Epub ahead of print]
Avian Influenza A(H5N1) and A(H9N2) Seroprevalence and Risk Factors for Infection Among Egyptians: A Prospective, Controlled Seroepidemiological Study.
Gomaa MR1, Kayed AS1, Elabd MA2, Zeid DA2, Zaki SA2, El Rifay AS2, Sherif LS2, McKenzie PP3, Webster RG3, Webby RJ3, Ali MA1, Kayali G3.
Author information
Abstract
BACKGROUND:
A(H5N1) and A(H9N2) avian influenza viruses are enzootic in Egyptian poultry, and most A(H5N1) human cases since 2009 have occurred in Egypt. Our understanding of the epidemiology of avian viruses in humans remains limited. Questions about the frequency of infection, the proportion of infections that are mild or subclinical, and the case-fatality rate remain largely unanswered.
METHODS:
We conducted a 3-year, prospective, controlled, seroepidemiological study that enrolled 750 poultry-exposed and 250 unexposed individuals in Egypt.
RESULTS:
At baseline, the seroprevalence of anti-A(H5N1) antibodies (titer, ≥80) among exposed individuals was 2% significantly higher than that among the controls (0%). Having chronic lung disease was a significant risk factor for infection. Antibodies against A(H9N2) were not detected at baseline when A(H9N2) was not circulating in poultry. At follow-up, A(H9N2) was detected in poultry, and consequently, the seroprevalence among exposed humans was between 5.6% and 7.5%. Vaccination of poultry, older age, and exposure to ducks were risk factors for A(H9N2) infection.
CONCLUSIONS:
Results of this study indicate that the number of humans infected with avian influenza viruses is much larger than the number of reported confirmed cases. In an area where these viruses are enzootic in the poultry, human exposure to and infection with avian influenza becomes more common.
? The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
KEYWORDS:
avian; cohort; epidemiology; influenza; seroprevalence
PMID:
25355942
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/25355942
Avian Influenza A(H5N1) and A(H9N2) Seroprevalence and Risk Factors for Infection Among Egyptians: A Prospective, Controlled Seroepidemiological Study.
Gomaa MR1, Kayed AS1, Elabd MA2, Zeid DA2, Zaki SA2, El Rifay AS2, Sherif LS2, McKenzie PP3, Webster RG3, Webby RJ3, Ali MA1, Kayali G3.
Author information
Abstract
BACKGROUND:
A(H5N1) and A(H9N2) avian influenza viruses are enzootic in Egyptian poultry, and most A(H5N1) human cases since 2009 have occurred in Egypt. Our understanding of the epidemiology of avian viruses in humans remains limited. Questions about the frequency of infection, the proportion of infections that are mild or subclinical, and the case-fatality rate remain largely unanswered.
METHODS:
We conducted a 3-year, prospective, controlled, seroepidemiological study that enrolled 750 poultry-exposed and 250 unexposed individuals in Egypt.
RESULTS:
At baseline, the seroprevalence of anti-A(H5N1) antibodies (titer, ≥80) among exposed individuals was 2% significantly higher than that among the controls (0%). Having chronic lung disease was a significant risk factor for infection. Antibodies against A(H9N2) were not detected at baseline when A(H9N2) was not circulating in poultry. At follow-up, A(H9N2) was detected in poultry, and consequently, the seroprevalence among exposed humans was between 5.6% and 7.5%. Vaccination of poultry, older age, and exposure to ducks were risk factors for A(H9N2) infection.
CONCLUSIONS:
Results of this study indicate that the number of humans infected with avian influenza viruses is much larger than the number of reported confirmed cases. In an area where these viruses are enzootic in the poultry, human exposure to and infection with avian influenza becomes more common.
? The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
KEYWORDS:
avian; cohort; epidemiology; influenza; seroprevalence
PMID:
25355942
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/25355942
