Identification of All Dengue Serotypes in Nepal

摘要

To the Editor: Nepal is situ-ated on the southern slopes of the Himalayas, surrounded by India on 3 sides and China to the north. Nepal's altitude ranges from 8,848 m in the Himalayas to 90 m in the Terai, the southern, low, . atland bordering In-dia. Nepal is a disease-endemic area for many vector-borne diseases, in-cluding malaria, kala-azar, Japanese encephalitis, and lymphatic fi lariasis. Because of the porous border between Nepal and India, social, cultural, and economic activities in cross-border ar-eas are common. Dengue is an emerging disease in Nepal; presumably transmission is moving north from India into the Terai (1–5). The fi rst report of dengue virus isolation or RNA (serotype 2 with nu-cleotide homology closest to a dengue virus type 2 isolate from India) was in 2008 involving a Japanese patient returning from Nepal in October 2004 (5). Entomologic investigations from the 1980s showed Aedes albopictus in the Terai plains, but Ae. aegypti has not been previously reported.After Indian outbreaks now known to include all 4 dengue sero-types (6), a team from the Epidemi-ology and Disease Control Division, Kathmandu, investigated suspected cases of dengue fever during Septem-ber–October 2006 in Banke, the dis-trict bordering Uttar Pradesh, India. The team collected blood samples from persons in Banke and, subse-quently, from persons in a number of other districts and sent them to the National Public Health Laboratory in Kathmandu or the Armed Forces Re-search Institute of Medical Sciences, Bangkok, Thailand for analysis with ELISA, reverse transcription–PCR, (RT-PCR), or both