Genetic signatures displayed by the CHIKV Lao isolates over the studied period (August 2012–December 2013).

<p>Genetic signatures displayed by the CHIKV Lao isolates over the studied period (August 2012–December 2013).</p

Chikungunya virus emergence in the Lao PDR, 2012–2013

<div><p>In May 2012, the first authenticated cases of active chikungunya virus infection were detected in Champasak Province, Southern Laos. Analysis of series of human samples and mosquito specimens collected during the outbreak and over the year that followed the emergence enabled the drawing up of a map of the progression of CHIKV and the establishment of a full genetic characterization of the virus.</p></div

Distribution of Chikungunya virus vectors and mosquito species composition from adult and larval collections in villages visited during the initial field investigation in August 2012 (see Fig 1A).

<p>Distribution of Chikungunya virus vectors and mosquito species composition from adult and larval collections in villages visited during the initial field investigation in August 2012 (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0189879#pone.0189879.g001" target="_blank">Fig 1A</a>).</p

Chikungunya virus study sites in 2012–2013.

<p>1A) Entomologic surveillance sites in September 2012. Black triangles represent villages in Moonlapamok and Khong Districts. Red stars represent villages where mosquito larvae were sampled. 1B) Chikungunya virus IgM seroprevalence in villages in Moonlapamok District. 1C) Chikungunya virus IgM seroprevalence in villages in Khong District. Letters correspond to the villages’ code and numbers to the recorded seroprevalence level.</p

Main symptoms recorded declared by the volunteers during the retrospective seroprevalence study in 2013.

<p>Main symptoms recorded declared by the volunteers during the retrospective seroprevalence study in 2013.</p

Virologic markers of CHIKV infection recorded in suspected cases recorded during the initial field investigation in August 2012.

<p>Virologic markers of CHIKV infection recorded in suspected cases recorded during the initial field investigation in August 2012.</p

Unadjusted and adjusted odds ratio for being HBsAg positive among children from five to nine years old in Lao PDR by selected background characteristics.

<p>Unadjusted and adjusted odds ratio for being HBsAg positive among children from five to nine years old in Lao PDR by selected background characteristics.</p

HBsAg prevalence among children (5 to 9 years old) and mothers (15 to 45 years old).

<p>HBsAg prevalence among children (5 to 9 years old) and mothers (15 to 45 years old).</p

HBsAg prevalence among children (5 to 9 years old) and mothers (15 to 45 years old) in Lao PDR by selected background characteristics.

1<p>Transportation to the nearest health facility, ² Time to the nearest health facility, ³ Mothers' completed education, ⁴ Family head's occupation.</p

Unadjusted and adjusted odds ratio for being HBsAg positive among mothers from 15 to 45 years old in Lao PDR by selected background characteristics.

<p>Unadjusted and adjusted odds ratio for being HBsAg positive among mothers from 15 to 45 years old in Lao PDR by selected background characteristics.</p