Environmental contamination and risk factors for transmission of highly pathogenic avian influenza A(H5N1) to humans, Cambodia, 2006-2010.
Highly pathogenic avian influenza A (H5N1) virus has been of public health concern since 2003. Probable risk factors for A(H5N1) transmission to human have been demonstrated in several studies or epidemiological reports. However, transmission patterns may differ according to demographic characteristics of the population and local practices. This article aggregates these data from three studies with data collected in the previous surveys in 2006 and 2007 to further examine the risks factors associated with presence of anti-A(H5) antibodies among villagers residing within outbreak areas.



We aggregated 5-year data (2006-2010) from serology survey and matched case-control studies in Cambodia to further examine the risks factors associated with A(H5N1) infection among villagers in the outbreak areas.



Serotesting among villagers detected 35 (1.5 % [0-2.6]) positive cases suggesting recent exposure to A(H5N1) virus. Practices associated with A(H5N1) infection among all ages were: having poultry cage or nesting area under or adjacent to the house (OR: 6.7 [1.6-28.3]; p = 0.010) and transporting poultry to market (OR: 17.6 [1.6-193.7]; p = 0.019). Practices found as risk factors for the infection among age under 20 years were swimming/bathing in ponds also accessed by domestic poultry (OR: 4.6 [1.1-19.1]; p = 0.038). Association with consuming wild birds reached borderline significance (p = 0.066).



Our results suggest that swimming/bathing in contaminated pond water and close contact with poultry may present a risk of A(H5N1) transmission to human.
Institut Pasteur in Cambodia, Phnom Penh, Cambodia.
Sowath
S
Ly
Institut Pasteur in Cambodia, Phnom Penh, Cambodia.
Sirenda
S
Vong
Institut Pasteur in Cambodia, Phnom Penh, Cambodia.|Agence de Médecine Préventive, Ferney-Voltaire, France.
Philippe
P
Cavailler
World Health Organization, Geneva, Switzerland.
Elizabeth
E
Mumford
Institut Pasteur in Cambodia, Phnom Penh, Cambodia.
Channa
C
Mey
Institut Pasteur in Cambodia, Phnom Penh, Cambodia.
Sareth
S
Rith
Institut Pasteur in Cambodia, Phnom Penh, Cambodia.|Institut Pasteur, Paris, France.
Maria D
MD
Van Kerkhove
National Veterinary Research Institute, Ministry of Agriculture Forestry and Fisheries, Phnom Penh, Cambodia.
San
S
Sorn
Communicable Disease Control Department, Ministry of Health, Phnom Penh, Cambodia.
Touch
T
Sok
Institut Pasteur in Cambodia, Phnom Penh, Cambodia. atarantola@pasteuur-kh.org.
Arnaud
A
Tarantola
Institut Pasteur in Cambodia, Phnom Penh, Cambodia. buchyphilippe@hotmail.com.|GSK Vaccines R&D, 150 Beach Road, 189720, Singapore, Singapore. buchyphilippe@hotmail.com.
Philippe
P
Buchy
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000835:Animals, Wild / Q000821:virology; D002160:Cambodia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks / Q000517:prevention & control / Q000706:statistics & numerical data; D004787:Environmental Pollution; D005260:Female; D006801:Humans; D007223:Infant; D053124:Influenza A Virus, H5N1 Subtype / Q000472:pathogenicity*; D005585:Influenza in Birds / Q000635:transmission* / Q000821:virology; D007251:Influenza, Human / Q000635:transmission* / Q000821:virology; D008297:Male; D008875:Middle Aged; D061005:Ponds / Q000821:virology*; D011200:Poultry / Q000821:virology*; D011634:Public Health; D012307:Risk Factors; D014873:Water Pollutants; D000069578:Waterborne Diseases / Q000635:transmission* / Q000821:virology*; D055815:Young Adult
D014873:Water Pollutants
A (H5N1); Environmental contamination; Human seroprevalence; Risk factors