Incidence and predictors of regimen-modification from first-line antiretroviral therapy in Thailand: a cohort study.

BACKGROUND: Antiretroviral therapy markedly reduced mortality in HIV-infected individuals. However, in the previous studies, up to 50% of patients are compelled to modify their regimen in middle and low-income countries where salvage drug is still limited. This cohort study aimed to investigate the incidence and predictors of regimen modification from the first-line antiretroviral regimen in northern Thailand. METHODS: All HIV-infected patients starting antiretroviral therapy (ART) with generic drug (GPOvir®; stavudine, lamivudine and nevirapine) at a governmental hospital in northern Thailand from 2002 to 2007 were recruited. Baseline characteristics and detailed information of regimen modification until the end of 2010 were ascertained from cohort database and medical charts. As a potential genetic predictor of regimen modification, HLA B allele was determined by bead-based array hybridization (WAKFlow® HLA typing kit). We investigated predictors of the regimen modification using Cox's proportional hazard models. RESULTS: Of 979 patients, 914 were eligible for the analysis. The observed events of regimen modification was 377, corresponding to an incidence 13.8/100 person-year-observation (95% CI:12.5-15.3) over 2,728 person years (PY) follow up. The main reasons for regimen modification were adverse effects (73.5%), especially lipodystrophy (63.2%) followed by rash (17.7%). Sixty three patients (17.1%) changed the regimen due to treatment failure. 2% and 19% of patients had HLA-B*35:05 and B*4001, respectively. HLA-B*35:05 was independently associated with rash-related regimen modification (aHR 7.73, 95% CI:3.16-18.9) while female gender was associated with lipodystrophy (aHR 2.11, 95% CI:1.51-2.95). Female gender (aHR 0.54, 95% CI: 0.30-0.96), elder age (aHR 0.56, 95% CI: 0.32-0.99) and having HLA-B*40:01 (aHR 0.29, 95% CI: 0.10-0.82) were protective for treatment failure related modification. CONCLUSION: HLA-B*35:05 and female gender were strong predictors of regimen modification due to rash and lipodystrophy, respectively. Female gender, elder age, and having HLA-B*40:01 had protective effects on treatment failure-related regimen modification. This study provides further information of regimen modification for future tailored ART in Asia.

Two N-linked glycosylation sites in the V2 and C2 regions of human immunodeficiency virus type 1 CRF01_AE envelope glycoprotein gp120 regulate viral neutralization susceptibility to the human monoclonal antibody specific for the CD4 binding domain.

A recombinant human monoclonal antibody, IgG1 b12 (b12), recognizes a conformational epitope on human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) gp120 that overlaps the CD4 binding domain. Although b12 is able to broadly neutralize HIV-1 subtype B, C, and D viruses, many HIV-1 CRF01_AE viruses are resistant to b12-mediated neutralization. In this report, we examined the molecular mechanisms underlying the low neutralization susceptibility of CRF01_AE viruses to b12, using recently established CRF01_AE Env recombinant viruses. Our results showed that two potential N-linked glycosylation (PNLG) sites in the V2 and C2 regions of Env gp120 played an important role in regulating the susceptibility of CRF01_AE Env to b12. The locations of these PNLG sites correspond to amino acid positions 186 and 197 in HXB2 Env gp120; thus, they are designated N186 and N197 in this study. Removal of N186 significantly conferred the b12 susceptibility of 2 resistant CRF01_AE Env clones, 65CC4 and 107CC2, while the introduction of N186 reduced the b12 susceptibility of a susceptible CRF01_AE Env clone, 65CC1. In addition, removal of both N186 and N197 conferred the b12 susceptibility of 3 resistant CRF01_AE Env clones, 45PB1, 62PL1, and 101PL1, whereas the removal of either N186 or N197 was not sufficient to confer the b12 susceptibility of these CRF01_AE Env clones. Finally, removal of N197 conferred the b12 susceptibility of 2 resistant CRF01_AE Env clones lacking N186, 55PL1 and 102CC2. Taken together, we propose that two PNLG sites, N186 and N197, in Env gp120 are important determinants of the b12 resistance of CRF01_AE viruses.

Amantadine- and oseltamivir-resistant variants of influenza A viruses in Thailand.

Amantadine and oseltamivir are used to treat influenza A virus infections; however, resistance to these drugs has been widely reported throughout the world. In this study, the frequency and genetic characteristics of the drug-resistant influenza A viruses that circulated in Thailand from 2006 to 2008 were investigated. The nucleotide sequences of the NA and M2 genes were elucidated in order to identify mutations that confer oseltamivir- and amantadine-resistant phenotypes, respectively. A total of 66 influenza A viruses including 44 H1N1 and 22 H3N2 subtypes isolated in Bangkok and 13 provinces of Thailand from 2006 to 2008 were analyzed. Our results demonstrated that seven out of 32 (22%) of the H1N1 viruses isolated in 2006 in Thailand carried the amino acid S31N substitution, which confers amantadine-resistance, although no isolates in 2007 or 2008 possessed the mutation. In the cases of oseltamivir-resistance, four of 10 (40%) of the H1N1 viruses isolated in 2008 were predicted to be resistant to the drug, although none of the 34 viruses isolated in 2006 or 2007 were predicted to be resistant. Surprisingly, all 9 H3N2 viruses isolated in 2008 appeared to be resistant to the amantadine and none were resistant in 2006 or 2007. Phylogenetic analysis based on the HA, M, and NA genes demonstrated that the amantadine-resistant H1N1 isolates had been produced by genetic reassortment. All of the amantadine-resistant H3N2 viruses were clustered in one of these three genes and possessed double mutations of S193F and D225N in the HA gene.

Substantially exposed but HIV-negative individuals are accumulated in HIV-serology-discordant couples diagnosed in a referral hospital in Thailand.

The objectives of this study is to characterize HIV-serology-discordant couples diagnosed at a referral hospital in Thailand and to identify risk factors for HIV transmission among married couples. Firstly, cross-sectional analysis was conducted from July 2000 to October 2002. Out of 216 HIV-positive married men who knew the HIV status of their wives, the median number of sexual contacts in 63 men with HIV-negative wives was 6 times per month before the disclosure of HIV status, which did not differ from 153 men with HIV-positive wives. The majority of men with HIV-negative wives never used condoms. The median duration of marriage was 7 years for both groups. Unlike in previous reports, men with HIV-negative wives were significantly more symptomatic (P<0.01), and their CD4+ counts and viral loads did not differ from men with HIV-positive wives. Secondarily, 71 initially discordant couples were longitudinally followed until March 2005. Four were seroconverted out of 132.24 person-years of observation. In multivariate analysis incorporating sex, age, CD4+ count and sexual contact without a condom, shorter duration of marriage (<2 years) was found to be the only risk factor significantly associated with HIV transmission (hazard ratio of 15.2, P=0.04). Individuals substantially exposed to HIV but remaining HIV-negative are accumulated in discordant couples identified in a hospital, except in recently married couples.

Demographic, socio-economic, behavioral and clinical factors predicting virologic failure with generic fixed-dose combination antiretroviral therapy before universal health insurance coverage in northern Thailand.

We conducted a 2-year prospective cohort study to investigate multiple aspects of factors predicting the outcome of fixed-dose combination antiretroviral (ARV) therapy with lamivudine, stavudine, and nevirapine (GPOvir) at a government referral hospital in northern Thailand. At 6 and 24 months after the initiation of GPOvir, viral load (VL) was measured to determine virologic failure (>400 RNA copies/ml) and demographic, socio-economic, behavioral and clinical data were collected. From 10 April 2002 to 31 January 2004, 409 patients participated in this study: 64/364 (17.0%) at 6 months and 55/345 (15%) at 24 months virologically failed treatment. On univariate analysis, besides ARV experience [odds ratio (OR), 3.08, 95% confidence interval (CI), 1.71 -5.57] and the frequency of delayed doses (OR, 2.97; 95% CI, 1.47-6.00), we identified one socioeconomic factor significantly associated with virologic failure: "not having child" (OR, 1.85; 95% CI, 1.03 - 3.34). Although the association with "not having child" became marginal on multivariate analysis, results of in-depth interviews and group discussions indicated that having a child was a strong motivating factor for good treatment compliance. We suggest that patients without children may need more attention. Further investigation of socio-economic factors is warranted.

A nationally coordinated laboratory system for human avian influenza A (H5N1) in Thailand: program design, analysis, and evaluation.

BACKGROUND: The first phase of national surveillance for avian influenza (H5N1) human disease in Thailand occurred over a 4-month period that began on 1 December 2003. Subsequently, a nationally coordinated laboratory system (NCLS) for avian influenza (H5N1) was created to assess population-based surveillance, specimen procurement, case detection, and reporting at the national level. METHODS: We conducted a pre- and postintervention study to evaluate the NCLS designed during the 6-week interval from 1 April through 15 May 2004. During the pre-NCLS period (1 December 2003 through 31 March 2004), 12 cases of human avian influenza (H5N1) were confirmed. During the post-NCLS period (16 May 2004 through 31 December 2006), interventions were implemented for human avian influenza (H5N1) surveillance, case detection, and expedited, computer-based reporting. RESULTS: During the pre- and post-NCLS periods, 777 (85%) of 915 and 10,434 (95%) of 11,042 clinical respiratory specimens, respectively, were adequate for confirmatory testing (P<.001), the median time from procurement to results decreased from 17 days (range, 14-24 days) to 1.8 days (range, 0.25-4 days; P<.001), and the duration of specimen shipment decreased from 46.5 h to 21.1 h (P<.001). Thirteen cases of avian influenza (H5N1) were detected during the 31-month postintervention period. H5N1 reverse-transcriptase polymerase chain reaction and real-time reverse-transcriptase polymerase chain reaction sensitivity was 100% and specificity was 99.8%. CONCLUSIONS: The NCLS exemplifies a systematic approach to national surveillance for avian influenza A (H5N1). This NCLS program in Thailand serves as a model for human avian influenza (H5N1) preparedness that can be adopted or modified for use in other countries.

Probable person-to-person transmission of avian influenza A (H5N1).

BACKGROUND: During 2004, a highly pathogenic avian influenza A (H5N1) virus caused poultry disease in eight Asian countries and infected at least 44 persons, killing 32; most of these persons had had close contact with poultry. No evidence of efficient person-to-person transmission has yet been reported. We investigated possible person-to-person transmission in a family cluster of the disease in Thailand. METHODS: For each of the three involved patients, we reviewed the circumstances and timing of exposures to poultry and to other ill persons. Field teams isolated and treated the surviving patient, instituted active surveillance for disease and prophylaxis among exposed contacts, and culled the remaining poultry surrounding the affected village. Specimens from family members were tested by viral culture, microneutralization serologic analysis, immunohistochemical assay, reverse-transcriptase-polymerase-chain-reaction (RT-PCR) analysis, and genetic sequencing. RESULTS: The index patient became ill three to four days after her last exposure to dying household chickens. Her mother came from a distant city to care for her in the hospital, had no recognized exposure to poultry, and died from pneumonia after providing 16 to 18 hours of unprotected nursing care. The aunt also provided unprotected nursing care; she had fever five days after the mother first had fever, followed by pneumonia seven days later. Autopsy tissue from the mother and nasopharyngeal and throat swabs from the aunt were positive for influenza A (H5N1) by RT-PCR. No additional chains of transmission were identified, and sequencing of the viral genes identified no change in the receptor-binding site of hemagglutinin or other key features of the virus. The sequences of all eight viral gene segments clustered closely with other H5N1 sequences from recent avian isolates in Thailand. CONCLUSIONS: Disease in the mother and aunt probably resulted from person-to-person transmission of this lethal avian influenzavirus during unprotected exposure to the critically ill index patient.

Higher in vitro susceptibility of human T cells to H5N1 than H1N1 influenza viruses.

Patients infected with H5N1 influenza A virus, who had a severe or fatal outcome, exhibited several characteristic clinical manifestations including lymphopenia. In this study, human CD4(+) T-cell lines and healthy donor-derived peripheral blood mononuclear cells (PBMCs) were examined for susceptibility to infection with Thai isolates of H5N1 in comparison to those of H1N1. Although cellular levels were variable between H5N1 and H1N1 in T-cell lines and PBMCs, rates of production of progeny virions were significantly higher in H5N1 infections, suggesting a more efficient release of virions. In addition, cytopathogenicity in PBMCs, leading to a decline in CD4(+) T-cell numbers, were much severer with H5N1 than H1N1. Thus, human T cells could be an important target for infection with H5N1.

The polymorphisms in DC-SIGNR affect susceptibility to HIV type 1 infection.

Dendritic cell-specific intercellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin (DC-SIGN) and its homologue DC-SIGNR (DC-SIGN related) have been thought to play an important role in establishing HIV infection by enhancing trans-infection of CD4(+)T cells in the regional lymph nodes. To identify polymorphisms associated with HIV-exposed seronegative (ESN) individuals in Thais, genomic DNA from 102 HIV-seronegative individuals of HIV-seropositive spouses, 305 HIV-seropositive individuals, and 290 HIV-seronegative blood donors was genotyped for two single nucleotide polymorphisms (SNPs) in DC-SIGN promoter (-139A/G and 336A/G), a repeat number of 69 bp in Exon 4 of DC-SIGN and DC-SIGNR, and one SNP in Exon 5 of DC-SIGNR (rs2277998A/G). We found that the proportion of individuals possessing a heterozygous 7/5 and 9/5 repeat and A allele at rs2277998 of DC-SIGNR in HIV-seronegative individuals of HIV-seropositive spouses was significantly higher than HIV-seropositive individuals [p = 0.0373, OR (95% CI) = 0.57 (0.32,1.01); p = 0.0232, OR (95% CI) = 0.38 (0.15,0.98); and p = 0.0445, OR (95% CI) = 0.61 (0.37,1.02), respectively]. Analysis after stratifying by gender showed that these associations were observed only in females but not in males. Moreover, HIV-seropositive females tend to have a homozygous 7/7 repeat more frequently than HIV-seronegative females with a marginal level of significance [p = 0.0556, OR (95% CI) = 1.79 (0.94,3.40)]. Haplotype analysis showed that the proportion of individuals possessing the 5A haplotype in HIV-seronegative females was significantly higher than HIV-seropositive females [p = 0.0133, OR = 0.50 (0.27,0.90)]. These associations suggest that DC-SIGNR may affect susceptibility to HIV infection by a mechanism that is different in females and males. Further studies are warranted to investigate the mechanisms of their function.

An efficient tool for surveying CRF01_AE HIV type 1 resistance in Thailand to combined stavudine-lamivudine-nevirapine treatment: mutagenically separated PCR targeting M184I/V.

Under programs organized by the government of Thailand, HIV-1-infected patients have been treated since 2002 with several regimens, including a tablet known as GPOvir, which contains lamivudine, stavudine, and nevirapine. The aim of this study was to establish an effective assay, based on mutagenically separated PCR (MS-PCR), with the goal of surveying GPOvir-resistant HIV-1 cases. To determine the target mutation point for the assay, we analyzed the patterns of acquired drug resistance in plasma samples from GPOvir-failed cases. Of 428 HIV-1-infected individuals treated with GPOvir at Lampang Hospital in northern Thailand from 2002 to 2004, 66 had detectable viral loads after 3 months of treatment. The HIV-1 sequences of these 66 GPOvir-failed cases and 55 pre-GPOvir baseline samples were analyzed. The most prevalent drug resistance mutation among the samples was the lamivudine resistance M184I/V mutation. Based on this finding, we developed a new MS-PCR assay to detect the M184I/V mutation, and evaluated the assay performance for detecting GPOvir-resistant CRF01_AE cases. Comparing the results of M184I/V MS-PCR and sequence analyses, we found a concordance rate of 95% and an overall sensitivity of the M184I/V MS-PCR for detecting GPOvir-resistant cases of 79%. Considering the relatively low price of the assay, approximately $12.50 per sample, M184I/V MS-PCR may be a candidate for monitoring a large number of GPOvir-treated patients, particularly in developing nations.

Protective effects of IL4-589T and RANTES-28G on HIV-1 disease progression in infected Thai females.

OBJECTIVE: To evaluate the effect of polymorphisms in interleukin-4 (IL4) and RANTES promoters on disease progression in HIV-1 infected Thais. DESIGN: Antiretroviral (ARV) drug-free HIV-1 infected females from the prospective cohort. METHODS: A total of 246 DNA samples were genotyped for IL4 and RANTES promoter polymorphisms by PCR-RFLP. Associations of genotype with HIV-1 disease progression were assessed with respect to baseline clinical data including plasma HIV-1 load, CD4 cell counts, and proportion of symptomatic/AIDS, and survival status during 3 years of follow-up. RESULTS: Patients with homozygous IL4-589T allele showed a significantly lower HIV-1 viral load (P = 0.005) and a higher CD4 cell count (P = 0.003) than the other patients with heterozygous IL4-589C/T or homozygous IL4-589C allele. Kaplan-Meier analysis demonstrated an apparent but insignificant trend towards better survival in homozygous IL4-589T patients. On the other hand, patients with RANTES-28G allele showed a significantly better survival while those with RANTES In1.1C allele without RANTES-28G showed a significantly poorer survival compared with those who did not possess either RANTES In1.1C or RANTES-28G (P = 0.02), although those polymorphisms only weakly associated with baseline viral load and CD4 cell counts. CONCLUSIONS: Our results implicate the significant protective effect of IL4-589T and RANTES-28G on HIV disease progression in Thais. In contrast, RANTES In1.1C without RANTES-28G had an accelerating effect on HIV disease progression.

Determination and geographic distribution of Orientia tsutsugamushi serotypes in Thailand by nested polymerase chain reaction.

Clotted blood samples of 240 scrub typhus patients were collected from 8 Regional Medical Sciences Centers in Thailand during 1999 to 2002. The serotypes of Orientia tsutsugamushi and their geographic distribution were determined. A nested polymerase chain reaction (PCR) was used to identify the serotypes of O. tsutsugamushi. The number of patients with positive results for O. tsutsugamushi was 25.0%. Two serotypes, Karp and Kato, were detected in these samples. No Gilliam serotype was detected from any of the study locations. The PCR products were sequenced using an automated DNA sequencer. The nucleotide sequence of gene encoding 56-kDa protein from these samples showed a high sequence homology with the reference sequence of O. tsutsugamushi Karp and Kato serotypes. O. tsutsugamushi Karp serotype was predominant throughout Thailand with the percentage of 96.8% of the total serotype-positive patients, whereas 3.2% for Kato serotype was observed only in the south. The highest number among the region of Karp serotype-positive patients of 31.6% was found in the northeast.

Different susceptibility of human immunodeficiency virus type 1 to Env gp41-derived synthetic peptides corresponding to the C-terminal heptad repeat region.

Two functional domains, alpha-helical heptad repeat 1 (HR-1) and HR-2, located in the N-terminal and C-terminal regions of human immunodeficiency virus type 1 (HIV-1) Env gp41, respectively, play an important role in the fusion process. Synthetic 34-amino-acid peptide that contains the HR-2 region, named C34, has been shown to inhibit the HIV-1 fusion process. Here, we prepared six representative peptides (C34-B1, -B2, -A, -C1, -C2, and -E from subtypes B, A, C, and E, respectively) according to the sequences from the HIV sequence database of Los Alamos. All the C34 peptides had lower ability to inhibit the primary isolates (subtypes B and CRF01_AE) than subtype B laboratory strain LAI. On the other hand, the L-2 cell clone, isolated from persistently LAI-infected MT-4 cells (MT-4/LAI), showed unique C34 peptide sensitivities. L-2 virus has the same sequences at HR-1 and HR-2 regions as LAI, but showed higher syncytia formation activity than LAI. Interestingly, the sensitivity of L-2 was higher to C34-B2 and -A but slightly lower to C34-C1 at higher concentrations than MT-4/LAI, while C34-B1, -C2, and -E showed similar activity against both viruses. Thus, in addition to the sequences of the C34 peptide as well as of the HR-1 and HR-2 regions in target viruses used for fusion assays, the fusion inhibitory activities of C34 peptides seem to be affected by viral factor(s) other than the gp41 alpha-helical heptad repeats.

Heterosexual transmission of novel CRF01_AE and subtype B recombinant forms of HIV type 1 in northern Thailand.

The increased proportion of CRFO1_AE/subtype B recombinant infections among injecting drug users raised a concern that such recombinant forms may also spread in a heterosexual population in Thailand. Using the BootScan method, we reanalyzed pol gene sequences among 114 heterosexually infected individuals in northern Thailand, who were tested for a drug-resistance genotype between July 2000 and July 2001. Two individuals were suspected of carrying a recombinant HIV-1. Thus we analyzed a nearly full-length HIV genome in the two individuals and their spouses. An identical recombinant form of CRF01_AE and subtype B was found in one couple, indicating that this recombinant virus was heterosexually transmitted. Interestingly, this recombinant form had multiple breakpoints in the core protein of Gag and both infected individuals had a high CD4+ cell count without antiretroviral therapy. CRFO1/subtype B recombinant forms exist in a heterosexual population in northern Thailand. Some recombinant virus may be associated with a slow rate of HIV disease progression.

Construction and characterization of an infectious molecular clone derived from the CRF01_AE primary isolate of HIV type 1.

An infectious molecular clone (named p95TNIH022) was constructed using long-range polymerase chain reaction products derived from a clinical isolate (95TNIH022) of HIV-1 CRF01_AE obtained from an asymptomatic Thai carrier in 1995. The virus in the supernatant from p95TNIH022-transfected 293T cells showed infectivity in peripheral blood mononuclear cells (PBMCs) as well as in MAGIC5 cells, which express CD4 and CCR5, but not in the original MAGI cells, indicating that p95TNIH022 is an infectious molecular clone with CCR5 tropism. Interestingly, p95TNIH022-derived virus induced profound cell killing in infected PBMCs, as in cells infected with the parental isolate.

Ability to induce p53 and caspase-mediated apoptosis in primary CD4+ T cells is variable among primary isolates of human immunodeficiency virus type 1.

Infection with human immunodeficiency virus type 1 (HIV-1) is associated with dramatic depletion of CD4(+) T cells, the major HIV-1-induced pathogenesis. Apoptosis has been suggested to play an important role for the T cell depletion and a number of mechanisms have been proposed for the apoptosis in T cells. Here, we compared the levels for apoptosis induction in primary peripheral blood mononuclear cells (PBMCs) among several laboratory strains and primary isolates of the HIV-1 subtypes B and E. The results showed that apoptosis in infected PBMCs, preferentially in CD4+ T cell population, became detectable around the time for virus production by flow cytometric terminal transferase dUTP nick end labeling (TUNEL) technique and staining with the nuclear dye Hoechst 33342. The abilities to induce apoptosis in PBMCs were highly variable in individual isolates. The increase of p53 protein in infected PBMCs, which was initiated before virus production, was observed in infected PBMCs and the levels of p53 protein were almost proportional to the rates of the isolates to induced apoptosis. The cells infected and cultured in the presence of Z-VAD-FMK had significantly decreased cell mortalities, indicating that activated caspases also played a significant role in the apoptosis. Thus, HIV-1-induced apoptosis in primary T cells was accompanied by the p53 protein and caspase activation at varied levels in primary isolates.

Early diagnosis of scrub typhus in Thailand from clinical specimens by nested polymerase chain reaction.

The early detection of scrub typhus in Thailand by nested polymerase chain reaction (PCR) is presented. The diagnosis of scrub typhus, from clinical samples obtained from hospitals in the northern part of Thailand, by nested PCR was compared to immunofluorescence (IF) and Weil-Felix (WF) tests. The primer pairs used for the nested PCR were designed on the basis of the nucleotide sequence of the gene that encodes the 56-kDa antigen, and RFLP analysis was used for identification. Clotted blood from 80 patients suspected of scrub typhus infection were tested. With the IF test, antibodies for Orientia tsutsugamushi were observed in 38 patients checking IgM and IgG titers. Only 21 patients showed positive seroconversion while 17 patients were negative. For the WF test, only 13 patients gave a positive seroconversion. In the early stage of infection, 19, 13 and 3 patients were detected with a sensitivity of 90.47% (19/21), 61.90% (13/21) and 14.28% (3/21) by the nested PCR, IF and WF test respectively. Two patients who were negative for seroconvesion by IF and WF were positive by nested PCR. Therefore, this suggests that nested PCR is applicable for specific rapid diagnosis at an early stage of scrub typhus in endemic regions.

The seroprevalence of human herpesvirus 8 infection in the Thai population.

The seroprevalence of human herpesvirus 8 (HHV-8) infection in the Thai population was investigated. Sera from 1,018 human immunodeficiency virus 1 (HIV-1)-negative and 436 HIV-1-positive individuals were tested for antibodies to latent and lytic HHV-8 antigens by indirect immunofluorescence assay (IFA) and an enzyme-linked immunosorbent assay (ELISA) using mixed recombinant orf HHV-8 proteins. The positive sera were further tested with recombinant HHV-8 protein expressed 293T cells by IFA. The seroprevalence of HHV-8 infection was determined by the concordant reactivity of sera among antibody testing assays. The results showed a low rate of HHV-8 seropositivity in both HIV-1-negative healthy individuals (0.6%) and HIV-1-infected patients (0.7%). These results are consistent with the fact that a small number of patients with AIDS-associated KS have been reported in Thailand and that HHV-8 is an uncommon pathogen in this country. Interestingly, we found that sera from the general population living in the north, but not other regions of Thailand, had antibodies to HHV-8.

Early containment of severe acute respiratory syndrome (SARS); experience from Bamrasnaradura Institute, Thailand.

BACKGROUND: On March 11, 2003, a World Health Organization (WHO) physician was admitted to Bamrasnaradura Institute, after alerting the world to the dangers of severe acute respiratory syndrome (SARS) in Vietnam and developing a fever himself. Specimens from the first day of his admission were among the first to demonstrate the novel coronavirus, by culture, reverse transcription-polymerase chain reaction (RT-PCR), and rising of specific antibody, but proper protective measures remained unknown. The authors instituted airborne, droplet and contact precautions from the time of admission, and reviewed the efficacy of these measures. MATERIAL AND METHOD: A specific unit was set up to care for the physician, beginning by roping off an isolated room and using a window fan to create negative pressure, and later by constructing a glass-walled antechamber, designated changing and decontamination areas, and adding high-efficiency particulate air (HEPA) filters. The use of personal protective equipment (PPE) was consistently enforced by nurse managers for all the staff and visitors, including a minimum of N95 respirators, goggles or face shields, double gowns, double gloves, full head and shoe covering, and full Powered Air Purifying Respirator (PAPR) for intubation. To assess the adherence to PPE and the possibility of transmission to exposed staff a structured questionnaire was administered and serum samples tested for SARS coronavirus by enzyme-linked immunosorbent assay (ELISA). Exposure was defined as presence on the SARS ward or contact with laboratory specimens, and close contact was presence in the patient's room. RESULTS: The WHO physician died from respiratory failure on day 19. 112 of 129 exposed staff completed questionnaires, and the 70 who entered the patient's room reported a mean of 42 minutes of exposure (range 6 minutes-23.5 hours). 100% reported consistent handwashing after exposure, 95% consistently used a fit-tested N95 or greater respirator, and 80% were fully compliant with strict institutional PPE protocol. No staff developed an illness consistent with SARS. Serum samples from 35 close contacts obtained after day 28 had a negative result for SARS coronavirus antibody. CONCLUSIONS: Hospitalization of one of the earliest SARS patients with documented coronavirus shedding provided multiple opportunities for spread to the hospital staff, but strict enforcement of conservative infection control recommendations throughout the hospitalization was associated with no transmission.

Changing burden of HIV/AIDS to clinical settings in Northern Thailand over 15 years.

We conducted a hospital-based descriptive study to describe the changing pattern of patient numbers, characteristics, and mortality rates among human immunodeficiency virus (HIV)-infected patients in northern Thailand over 15 years. The survival status on October 31, 2010 of all HIV-infected adults who attended an HIV center in a government hospital between 1995 and 2010 was ascertained. In total, 3,706 patients were registered, 2,118 (57.2%) of which were male. The survival status of 3,439 patients (92.9%) was available. In addition, 1,543 deaths were identified out of 12,858 person-year-observations (PYO) resulting in a mortality rate of 12.4 deaths/100 PYO (95% confidence interval [CI], 11.3-13.0). An initial decline in mortality rates was observed prior to 1999, probably because of an increase in the proportion of less symptomatic patients. After the introduction of the national highly active antiretroviral therapy (HAART) program, a profound decline in mortality rates was observed, reaching 2.0 deaths/100 PYO (95% CI, 1.4-2.9) in 2010. Simultaneously, the number of patients on follow-up increased by nearly fourfold. Although HAART has drastically improved the survival of HIV-infected patients, the number of patients receiving therapy at this HIV clinic has substantially increased. While referral of HIV patients to general physicians' care should be urged, we cannot overemphasize the importance of preventing new HIV infections.