Volume 23, Number 2—February 2017
Seroprevalence and Transmission of Human Influenza A(H5N1) Virus before and after Virus Reassortment, Cambodia, 2006–2014
|Reference||Country, population type||Year||Clade||Testing method||Village population||No. positive/no. tested||% Positive (95% CI)†|
|(5)||Cambodia, villagers||2005||1||MN, WB||1,146||0/351||0 (0–0.01)|
|(6)||Cambodia villagers||2006||1||MN||1,192||7/674||1.0 (0–2.2)|
|(2)||Cambodia villagers||2007||1.1.1||MN, HI||847||18/700||2.6 (0.2–4.1)|
|Unpub. data||Cambodia, villagers||2009||1.1.1||MN, HI||927||10/622||1.6 (0.9–3.0)|
|Unpub. data||Cambodia, villagers||2010||1.1.2||MN, HI||452||0/366||0 (0–0.01)|
|This study||Cambodia, villagers||2014||1.1.2R‡||MN, HI||695||1/238||0.4 (0.1–3.0)|
|This study||Cambodia, villagers||2014||1.1.2R‡||MN, HI||921||1/643||0.1 (0.0–1.1)|
|Cambodia, 2004–2010 studies||4,564||35/2,713||1.3 (0.9–1.8)|
|Cambodia, 2014||1,616||2/881||0.2 (0.1–0.9)|
|Cambodia, all studies 2004–2014||6180||37/3,594||1.0 (0.7–1.4)|
*Positive results were determined by using World Health Organization criteria. HI, hemagglutination inhibition assay; MN, microneutralization assay; WB, Western blot.
†Poisson interval. An additional study conducted in 2008 in Cambodia focused on 394 soldiers (majority), support personnel, and their families in a confirmed H5N1 virus hotspot. No infections were found (prevalence 0%; 95% CI 0.0%–0.01%). The collective exposure was different from previous studies (soldiers had little or no exposure to poultry), so these data were not included in the table.
‡Clade 1.1.2 reassortant strain with internal and matrix genes originating from clade 22.214.171.124.
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