Zika Virus risk in Siem Reap

Zika Virus Prevention Guide for Siem Reap

Zika is a mosquito-borne viral infection spread primarily through the bite of an infected Aedes mosquito. Most people experience mild symptoms such as fever, rash, joint pain, and red eyes, though many show no symptoms at all. The serious concern is for pregnant women, as Zika can cause severe birth defects including microcephaly.

Siem Reap carries a moderate risk score of 63 out of 100. Local factors contributing to this risk include the tropical climate with year-round warm temperatures and a distinct rainy season from May through October, which creates abundant standing water for mosquito breeding. The dense tourist population around the Angkor temple complex means travelers from various regions may introduce or carry the virus. Urban and semi-urban areas with inadequate water storage and drainage systems provide ideal mosquito habitats. Additionally, outdoor activities like temple tours at dawn and dusk peak mosquito activity times increase exposure risk.

Here are your key prevention steps.

Apply DEET-based insect repellent containing 20 to 30 percent concentration on exposed skin, reapplying every four to six hours, especially during early morning and late afternoon when Aedes mosquitoes are most active.

Wear long-sleeved shirts, long pants, and socks, particularly when visiting the Angkor Archaeological Park and other outdoor sites where vegetation and standing water are present.

Choose accommodations with air conditioning or intact window and door screens. If your room lacks these, use a bed net, preferably one treated with permethrin, and check for and eliminate any standing water in buckets, flower pots, or containers near your lodging.

Avoid areas with poor drainage or open water storage around Siem Reap town, especially near the moat surrounding the temples where mosquito populations concentrate.

Pregnant women should reconsider travel to Siem Reap given the elevated risk, and all travelers should monitor for symptoms for two weeks after departure and seek medical attention if fever, rash, or joint pain develop.