RESUMEN
Two HIV-1 strains, CRF01_AE and subtype B', were reported in Thailand during the early years of the epidemic. Recently, an intersubtype recombination of HIV-1 strain was found in Thailand. Eight-hundred and twenty-eight samples collected during years 1995-2004 from high-risk groups in Bangkok, northern, northeastern, and southern region of Thailand were studied. HIV-1 env nucleotide sequences were used for phylogenetic analysis of the circulating HIV-1 strain. By single HIV-1 region (env) genotyping, CRFO1_AE was found in 97.3% and HIV-1 subtype B was found in 2.7%. A predominance of CRF01_AE was found in all geographic regions. Parallel analysis of the HIV-1 gag and env genes demonstrated that 2.1% and 4.0% of recombinant HIV-1 strains were found using p17 and p24 region sequences, respectively. The recombinant gag gene was also found in one southern isolate. Phylogenetic analysis of HIV-1 isolated from 20 provinces in 2002 suggested the northern and northeastern isolates were more related than the southern isolates which had the lowest genetic diversity of 0.13. The GPGQ V3 loop tip was also present in isolates from all regions. The molecular epidemiological data from this study may be useful for surveillance design as well as targeting prevention efforts. It also provides information regarding new antigenic regions of circulating strains responsible for the HIV-1 epidemic in Thailand.
Asunto(s)
Infecciones por VIH/virología , VIH-1/clasificación , VIH-1/genética , Secuencia de Aminoácidos , Secuencia de Bases , Femenino , Genes env , Genes gag , Variación Genética , Glicosilación , Infecciones por VIH/epidemiología , VIH-1/aislamiento & purificación , VIH-1/metabolismo , Humanos , Masculino , Datos de Secuencia Molecular , Filogenia , Recombinación Genética , Vigilancia de Guardia , Tailandia/epidemiologíaRESUMEN
BACKGROUND: The Ministry of Public Health (Thailand), MoPH, has had a program called National Access to Antiretroviral Program for People who have AIDS (PHA) or "NAPHA", to offer free antiretroviral drugs (ARV), which are locally produced in Thailand, to any HIV-1 infected patients with CD4<200 since 2002. This program may increase usage of ARV therapy and the emergence of HIV-1 drug resistance. OBJECTIVES: To monitor HIV-1 ARV drug resistant codon mutation in Thailand before and after the "NAPHA" program. MATERIALS AND METHODS: EDTA blood samples were collected from 542 HIV-1 infected subjects, who received ARV therapy in 1999 and 2001-2003, and perinatal chemoprophylaxis in 1998 and 2000. HIV-1 pol nucleotide sequences were analyzed. RESULTS: The percentage of drug resistant detection from the ARV therapy group in 1999 and 2001-2003 were 12.14 (34/280), 10.23 (9/88), 86.96 (20/23) and 57.55 (61/106), respectively. Of 332 NRTI drug resistant codon mutation, 226 (68.07%) were thymidine analogue mutations (TAMs). The percentage of TAMs detection in 1999 and 2001-2003 were 7.14 (20/280), 9.09 (8/88), 56.52 (13/23) and 43.34 (46/106), respectively. Of 105 NNRTI drug resistant codon mutation, 95 (90.48%) were related to nevirapine drug resistance. CONCLUSION: Thailand may need more appropriate monitoring of drug resistance in the free ARV therapy program to protect the future usage of drugs by minimizing the emergence of drug resistance.
Asunto(s)
Antirretrovirales/farmacología , Farmacorresistencia Viral/genética , Programas de Gobierno , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Encuestas Epidemiológicas , Antirretrovirales/uso terapéutico , Genes pol , Infecciones por VIH/tratamiento farmacológico , Transcriptasa Inversa del VIH/genética , VIH-1/genética , Humanos , Mutación , Nevirapina/farmacología , Inhibidores de la Transcriptasa Inversa/farmacología , Tailandia , Timidina/genética , Resultado del TratamientoRESUMEN
The usage of dried blood spots as specimens for diagnosis and monitoring of HIV-1 infection in Thailand was evaluated. EDTA blood samples, which were collected from 100 HIV seronegative and 109 HIV seropositive individuals, were tested on dried blood spots; Whatman, Schleicher and Schuell (S&S) No. 903 and S&S IsoCode filter paper. Nucleic acid was extracted and used as a template for HIV-1 proviral DNA detection by an "in-house" multiplex PCR and a commercial Amplicor HIV-1 PCR test (Roche, version 1.0). HIV-1 RNA qualitative (QL) and quantitative (QT) detection was determined by Nucleic Acid Sequence Based Amplification (NASBA). The average DNA per blood spot recovered from Whatman and S&S IsoCode was not statistically different (p = 0.512) with a range of 218.9+/-46.84 and 225.63+/-88.33 microg, respectively. The concordance of HIV-1 proviral DNA detection by PCR from dried blood spots Whatman and S&S IsoCode was 94% versus 89.4% for sensitivity and 100% versus 100% for specificity. The sensitivity and specificity of HIV-1 RNA QL detection in dried blood spots was 89.7 and 97.5%, respectively. The HIV-1 RNA QT from dried blood spots showed a good correlation in paired dried blood spots and plasma with Pearson correlation, r = 0.817 (R2 = 0.667, P < 0.05). The data showed that dried blood spots could be used for the diagnosis and monitoring of HIV-1 infection.