Nondetection of HTLV-I/II and HIV-2 in Thailand 1991-1992 [letter]

This paper presents findings from the first documented survey of HIV-2 in Thailand. The authors collected 550 serum specimens from June 1991 to February 1992. 250 were from consecutive IV drug users attending Thanyarak Hospital near Bangkok 200 were from consecutive female prostitutes attending the public sexually transmitted diseases clinic at Bangrak Hospital and 100 were from brothel-based female prostitutes working in Chiangrai the northernmost province of Thailand. Demographic and risk information were collected by questionnaire while blood sera were screened with ELISA and Western blot (WB) tests. No specimen was seropositive for HTLV-I/II and 149 sera were seropositive for HIV-1. The search for HIV-2 was conducted retrospectively among stored research specimens from a variety of populations tested by the HIV/AIDS Collaboration Laboratory over the period May 1991-December 1992. 91 ELISA-reactive but HIV-1 WB-indeterminate or WB-negative specimen were retested for HIV-2 using the Genetic Systems Genie HIV-1/HIV-2 rapid synthetic-peptide ELISA test and any specimens reactive to HIV-2 by Genie were further tested by HIV-2 WB. No specimen was seropositive for HIV-2. These findings suggest that HTLV-I/II and HIV-2 may be rare in Thailand. Larger and more inclusive studies may be needed to decide whether blood-donor testing for these viruses in addition to HIV-1 is indicated in Thailand.