Persistence of antibodies to the surface antigen of the hepatitis B virus (anti-HBs) in children subjected to the Expanded Programme on Immunization (EPI), including hepatitis-B vaccine, in Thailand

Will hepatitis-B vaccine administered at birth, and at 2 and 6 months of age, as an integral part of Thailand's Expanded Programme on Immunization, provide long-term protection? In an attempt to answer this question, residents of five provinces (representing five distinct geographical areas of Thailand) who were aged 1-10 years and had received this course of vaccination were enrolled on a serological study. Each was tested, with ELISA, for the surface antigen of hepatitis B (HBsAg) and for antibodies against this antigen (anti-HBs) or against the core antigen (anti-HBc). Over all age-groups, the prevalences of HBsAg, anti-HBs and anti-HBc were 0.67%, 71.4% and 5.5%, respectively. Although the prevalence of anti-HBs decreased with age, it remained at 56%-65% among those aged 6-10 years. Between 2% and 17% of the subjects aged 1-9 years had high titres of anti-HBs. Based on these results, an additional booster, still a controversial issue, does not appear to be required in order to prevent infection with hepatitis B virus and thus permit the eventual eradication of chronic carriage and its fatal sequelae in Thailand.     

Increasing susceptibility to HAV among members of the young generation in Thailand

The prevalence of antibodies to hepatitis A virus was studied in 961 children and adolescents, randomly selected from five different provinces in Thailand (Chonburi, Lopburi, Udonthani, Nakhon Si Thammarat and Lopburi). The highest prevalence was found in Nakhon Si Thammarat, with 32.1 percent of those aged 10-14 years and 57.1 percent of those aged 15-18 years showing evidence of protective immunity. However, this high rate could be explained by an outbreak of hepatitis A in 1992. In the remaining four provinces, the pattern was typically age-related in that all individuals showed between zero and 13 percent antibody prevalence until reaching the 15-to-18-year age group where it increased to between 5.6 and 22.7 percent. The overall sero-prevalence among all age groups was 7.9 percent. Thus, the majority of the younger generation is susceptible to hepatitis A virus infection thereby enhancing the impact, should an outbreak occur. Preventive measures that might be taken are education aimed at better hygiene and sanitation, as well as vaccination of susceptible individuals within high-risk populations.     

HIV/AIDS care and treatment in three provinces in northern Thailand before the national scale-up of highly-active antiretroviral therapy

In 2003, Thailand launched a program to place 50,000 persons on highly active antiretroviral therapy (HAART) by the end of 2004, following a series of efforts since the early 1990s to develop comprehensive HIV/AIDS care services. To evaluate existing services and needs in advance of the national HAART scale-up, in 2002 we surveyed 31 hospitals and 389 community health centers in three northern Thai provinces, and interviewed 1,015 HIV-infected patients attending outpatient clinics. All hospitals offered voluntary HIV counseling and testing, 84% provided primary prophylaxis for Pneumocystis carinii pneumonia, 58% for tuberculosis, 39% for cryptococcal meningitis, and 87% had some experience providing antiretroviral therapy. Community health centers provided more limited service coverage. Of patients interviewed, 63% had been diagnosed with symptomatic HIV disease, and of these, 32% reported ever receiving antiretroviral therapy; 51 % of all patients had received a CD4 T-lymphocyte count. Thailand's current national HAART scale-up is being performed in a setting of well-developed hospital-based services introduced over the course of the epidemic.     

Relative efficacy of fluocinolone acetonide compared with triamcinolone acetonide in treatment of oral lichen planus

Twenty patients with oral lichen planus and topically treated with fluocinolone acetonide in orabase 0.1% (FAO) were compared with 20 treated with triamcinolone acetonide in orabase 0.1% (TAO). During 4 wk of treatment the lesions in 13 of 19 patients could be effectively cured with FAO whereas only 8 of 19 patients were cured with TAO. These differences were statistically significant. There were no differences in blood pressure, plasma cortisol or number of circulating lymphocytes after treatment with FAO, but the number of eosinophils was reduced in every case after treatment for 6 months. There was no permanent adrenal cortical suppression after treatment for 6 months. Acute pseudomembranous candidiasis during the treatment was common but could be cured with antifungal drug in every case. This study shows that FAO in a majority of cases is an effective treatment of oral lichen planus without any serious clinical side effects apart from treatable candidiasis.     

Risk factors for HIV among prostitutes in Chiangmai, Thailand

The discovery of a 44% (44 out of 100) prevalence rate of HIV infection among female prostitutes working in brothels in Chiangmai in Thailand in June 1989, prompted this follow-up study in August to confirm the high prevalence rate and to look for risk factors for infection. We studied 238 female prostitutes working in 14 brothels and confirmed this high prevalence rate. Eighty-seven (36.5%) out of 238 prostitutes were found to be HIV-positive by enzyme-linked immunosorbent assay with IFA or Western blot confirmation. Logistic regressions found a significant association between HIV infection and frequency of sexual intercourse greater than 3 times per day [odds ratio (OR) = 2.82, 95% confidence interval (CI) = 1.47-5.41], sexual service charge less than 150 Baht (OR = 9.1, 95% CI = 2.9-33.3), and post sexual cleansing with water alone (OR = 3.85, 95% CI = 1.90-7.80). Of 56 women found seronegative in the June survey, 35 were re-tested in the August study. Seven (20%) of them were seropositive, giving an HIV seroconversion incidence rate of 10% per month. The findings of this study prompted intensive health education programmes among prostitutes, their customers, and owners of brothels.     

Antiretroviral therapy during tuberculosis treatment and marked reduction in death rate of HIV-infected patients, Thailand

Antiretroviral therapy (ART) is lifesaving in patients with advanced HIV infection, but the magnitude of benefit in HIV-infected patients receiving tuberculosis (TB) treatment remains uncertain, and population-based data from developing countries are limited. We prospectively collected data about HIV-infected TB patients from February 2003 through January 2004 in Ubon-ratchathani, Thailand. During 12 months, HIV was diagnosed in 329 (14%) of 2,342 patients registered for TB treatment. Of patients with known outcomes, death during TB treatment occurred in 5 (7%) of 71 who received ART and 94 (43%) of 219 who did not. Using multivariate analysis, we found a large reduction in the odds of death for patients receiving ART before or during TB treatment (odds ratio, 0.2; 95% confidence interval, 0.1-0.5), adjusting for CD4 count, smear status, co-trimoxazole use, and treatment facility. ART is associated with a substantial reduction in deaths during TB treatment for HIV-infected TB patients in Thailand.     

Impact of hepatitis B immunisation as part of the EPI

Since 1992, hepatitis B vaccine has been an integrated part of Thailand's expanded programme on immunisation (EPI). Based on the data from five representative provinces, we have evaluated its impact on the countrywide prevalence of HBV infection and carrier rate. The population studied comprised 400-488 healthy and immuno-competent, subjects per area. The subjects' ages ranged from 6 months to 18 years. We examined their sera for viral hepatitis markers using commercially available test kits and established the coverage rate of hepatitis B vaccination after its inclusion into the EPI to be 71.2-94.3%. The number of individuals undergoing the complete course of vaccinations had increased four-fold. Consequently, only 0.7% of the children born after the implementation of this the novel EPI strategy were HBV carriers.     

Risk factors of HIV-1 infection among female prostitutes in Khon Kaen,northeast Thailand

Summary HIV infection has increased to epidemic proportions in Thailand since 1987. There have been separate epidemics among population groups at high risk of infection and significant increases in different localities. The northeast region of Thailand has been affected by the epidemic since early 1989. The purpose of this study was to identify factors associated with HIV transmission among prostitutes during an early phase of the epidemic in the regional center of Khon Kaen. Three hundred and fifty-six prostitutes known to work in the urban area of Khon Kaen (Ampur Muang) in November 1990 were included in the study. Prostitutes were divided into two groups according to the type of place where they worked: direct prostitutes (in brothels, n=217) and indirect prostitutes (in massage parlors, n=139). The prevalence of HIV infection was found to be 12% among direct prostitutes and 2% among indirect prostitutes. Four variables were significantly associated with HIV infection after adjusting for confounders by logistic regression analysis: previous work in an area of high HIV prevalence, working in Khon Kaen less than one month, a low price charged for sex and using injectable contraceptives. Follow-up investigations are currently being carried out to explore in detail the association between the use of injectable contraceptives and HIV infection.

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Risikofaktoren einer HIV-1-Infektion bei weiblichen Prostituierten in Khon Kaen, Nordost-Thailand

Zusammenfassung Seit 1987 nahm die Ausbreitung von HIV in Thailand epidemische Ausmaße an. Bevölkerungsgruppen mit hohem Infektionsrisiko wurden in den verschiedenen Regionen von zeitlich unterscheidbaren Epidemien erfaßt. Die Nordost-Region wurde vergleichsweise spät, erst 1989 betroffen. Der Zweck dieser Studie war die Identifizierung von Faktoren, die mit der übertragung von HIV bei Prostituierten in der Provinzhauptstadt Khon Kaen während der Frühphase der Epidemie assoziiert waren. 356 Prostituierte wurden im November 1990 in die Studie aufgenommen. Sie wurden gemäß ihrem Arbeitsplatz in direkte Prostituierte (in Bordellen, n=217) und indirekte Prostituierte (in Massage-Salons, n=139) gruppiert. Die HIV-Prävalenz betrug bei den direkten Prostituierten 12% und 2% bei den indirekten Prostituierten. Vier Variablen waren signifikant mit einer HIV-Infektion assoziiert, nachdem eine logistische Regressions-Analyse durchgeführt wurde: vorangegangene Tätigkeiten in einer Region mit hoher HIV-Prävalenz, Prostitution in Khon Kaen weniger als einen Monat, ein niedriger Preis, der für Sex gefordert wurde und die Anwendung injizierbarer Kontrazeptiva. Gegenwärtig werden weitere Untersuchungen durchgeführt, um den Zusammenhang zwischen der Anwendung injizierbarer Kontrazeptiva und einer HIV-Infektion im Detail zu eruieren.

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The project is commissioned by the Ministry for Economic Cooperation, Germany.     

Acceptance of HIV testing and counseling among unmarried young adults in Northern Thailand.

A cluster randomized trial was used to assess the effect of an active group intervention in promoting utilization of voluntary HIV testing and counseling (HIV-TC). Villagers from 40 clusters were sampled to represent the premarital age population and assigned into two groups, intervention and comparison. The intervention was designed to enhance risk perception and increase knowledge about HIV testing. Interviews were performed before and after the intervention. At baseline, 23% of 398 participants had been tested for HIV at least once and 90% reported testing positive. Most participants perceived that they had no chance of being infected with HIV. Among the intervention group, 71% participated in the intervention activities. The risk ratio of HIV-TC acceptance among the intervention group was 2.92, but the risk difference was only 8.11%. Factors associated with HIV-TC acceptance were ever having had a sexually transmitted disease, being previously married, intention to get tested, and having partici pated in AIDS-related activities.