Injection prevalence and risks among male ethnic minority drug users in northern Thailand

Thailand's rate of HIV due to drug use is increasing, and nearly one-half of clients at a drug treatment centre in the north are from marginalized ethnic minority groups. We describe and compare socio-demographics, drug use, and sexual practices across ethnic minority people presenting for treatment at the Northern Drug Treatment Center, Mae Rim, Thailand. A prevalence study was conducted between February 1999 and January 2000. Trained interviewers administered a baseline questionnaire to 1,865 people admitted to the Northern Drug Dependence Treatment Center. Ethnic minority (Karen, Akha, Hmong, Lisu, and Lahu) males were included in this analysis (n = 629). Between 7% and 28% of each minority group had ever injected drugs (p = 0.002). Ninety-five per cent of men ever injecting had used heroin. Younger age, speaking Thai language, having a job with higher contact with Thais, and prior drug detoxification were significantly associated with injection in multivariate analysis, while Hmong and Lisu ethnicity were protective. Using occupation and language as proxies, contact with Thais and concomitant acculturation may be a risk for injection among this population. The inadvertent consequences of acculturation as it relates to injection and HIV risk must be addressed.

HIV-1 subtype E progression among northern Thai couples: traditional and non-traditional predictors of survival

BACKGROUND

In the continuing effort to introduce antiretroviral therapy in resource-limited settings, there is a need to understand differences between natural history of HIV in different populations and to identify feasible clinical measures predictive of survival.

METHODS

We examined predictors of survival among 836 heterosexuals who were infected with HIV subtype CRF01_AE in Thailand.

RESULTS

From 1993 to 1999, 269 (49.4%) men and 65 (25.7%) women died. The median time from the estimated seroconversion to death was 7.8 years (95% confidence interval 7.0-9.1). Men and women with enrolment CD4 counts <200 cells/microl had about 2 and 11 times greater risk of death than those with CD4 counts of 200-500 and >500, respectively. Measurements available in resource-limited settings, including total lymphocyte count (TLC), anaemia, and low body mass index (BMI), also predicted survival. Men with two or more of these predictors had a median survival of 0.8 (0.5-1.8) years, compared with 2.7 (1.9-3.3) years for one predictor and 4.9 (4.1-5.2) years for no predictors.

CONCLUSIONS

The time from HIV infection to death appears shorter among this Thai population than among antiretroviral naive Western populations. CD4 count and viral load (VL) were strong, independent predictors of survival. When CD4 count and VL are unavailable, individuals at high risk for shortened HIV survival may be identified by a combination of low TLC, anaemia, and low BMI. This combination of accessible clinical measures of the disease stage may be useful for medical management in resource-limited settings.

Methamphetamine users in northern Thailand: changing demographics and risks for HIV and STD among treatment-seeking substance abusers

Our objective was to determine sociodemographic, sexual and drug-use-related risk factors among methamphetamine (MA) users presenting for drug treatment in northern Thailand. Patients admitted for drug detoxification for MA and other drugs were studied cross-sectionally for risk factors associated with substance abuse and blood-borne and sexually transmitted pathogens. In all, 1865 (200 women) patients treated for MA, opiate, and mixed substance abuse between 1 February 1999 and 31 January 2000 completed all study procedures. Among 1865 participants, 750 (40.2%) were admitted for MA detoxification and 1115 (59.8%) for opiate (heroin, opium, or both) treatment. MA users were significantly younger, better educated, more likely to be Thai than highland ethnic minorities, and had significantly different sexual risks and sexually transmitted disease rates, including lower syphilis seropositivity and higher chlamydial prevalence, than persons admitted for opiate or mixed drug treatment. For those who reported MA use only, use by injection was rare and HIV infections significantly less common than among all other drug users. Thailand is undergoing an epidemic of MA use. These young users are a strikingly different population from opiate/heroin users in northern Thailand. MA users had higher rates of chlamydia infection than opiate users, reflecting their young age, and HIV rates in this population were lower than injecting drug users, but still elevated. MA use is a serious public health problem in Thailand and both improved prevention and treatment methodologies are urgently needed.

HLA class I serotypes and cytotoxic T-lymphocyte responses among human immunodeficiency virus-1-uninfected Thai volunteers immunized with ALVAC-HIV in combination with monomeric gp120 or oligomeric gp160 protein boosting

Antigen-induced cellular immunogenicity may vary between populations due to differences in human leukocyte antigen (HLA) diversity and, hence, may play a critical role in the protection afforded by vaccines. In the setting of two, phase I/II human immunodeficiency virus-1 vaccine trials of a recombinant canarypox prime, and boosting with either recombinant monomeric gp120 or oligomeric gp160, we assessed the association between specific human leukocyte antigen (HLA) class I serotypes and the presence of cytotoxic T-lymphocyte response measured by 51Cr-release assay. HLA class I serotypes A11, A24, A33, B46, and B75 were the most common, present in 10% or more of 245 individuals studied. Forty of 187 (21.4%) Thai adults who received either ALVAC-HIV with gp120 or oligomeric gp160 or ALVAC alone had a precursor cytolytic CD8 T-cell response (pCTL). HLA-B44 was positively and significantly associated with a pCTL response (odds ratio 7.6, 95% CI: 2.7-21.2), whereas B46 was negatively associated but not robust when adjusted for multiple comparisons. Responses to Env proteins accounted for the majority (nine of 11) of pCTL activity among those persons with B44. This HLA class I serotype occurred in 9.4% of participants overall (including the placebo group), less commonly than what is reported from populations of European ancestry. These results strengthen the importance of assessing HLA class I distributions in conjunction with studies of vaccines designed to elicit cellular immunity in different populations.

A phase I/II trial of HIV SF2 gp120/MF59 vaccine in seronegative thais.AFRIMS-RIHES Vaccine Evaluation Group. Armed Forces Research Institute of Medical Sciences and the Research Institute for Health Sciences

Fifty-two human immunodeficiency virus type 1, seronegative Thai adults from the community were enrolled in a double-blind, placebo controlled, phase I/II trial of HIV SF2 gp120/MF59 vaccine to determine the safety and immunogenicity of this recombinant, B clade, HIV envelope protein vaccine. Twenty-six subjects were enrolled at each of two sites in Thailand, Bangkok and Chiang Mai. Twelve subjects received placebo and 40 subjects received vaccine (50 microg). Subjects were immunized according to one of two schedules, 0, 1 and 4 or 0, 1 and 6 months. The frequency of adverse reactions was not different between placebo and vaccine subjects, nor between immunization schedules. Of vaccinees, all developed high-titer binding antibody to the immunogen (rgp120), 39 developed neutralizing antibody (NA) responses against homologous virus (HIV-1(SF2)), and 22 developed NA against heterologous virus (HIV-1(MN)). No subject demonstrated intercurrent HIV infection, however screening EIA reactivity occurred in 27% of recipients. Thus, this candidate HIV vaccine was found to be safe and immunogenic in Thai adults, laying the foundation for development of a subtype E construct in this population.

Factors influencing marital stability among HIV discordant couples in northern Thailand

The burden of HIV in stable relationships places emotional, economic and physical stresses on families. We compared the influence of HIV notification on marital partnerships in northern Thailand among a cohort of HIV discordant couples, and identified factors associated with marital disruption. Data were collected using in-depth interviews with both members of six separated or divorced couples and 13 couples whose relationship remained intact. Five factors influenced marital stability following HIV notification: longer duration of relationship; economic constraints, extended family members' opinions, especially parents; the existence of children from the marriage; and fear of stigmatization by community members. Social influences, both overt and perceived, are important in shaping marital behaviour and decision-making in HIV epidemic areas. HIV counselling needs to be extended beyond the individual seeking testing to include stable partners (and perhaps further, to include the extended family), although it is recognized that this is not the norm for most HIV testing centres.

High rates of transmission of subtype E human immunodeficiency virus type 1 among heterosexual couples in Northern Thailand: role of sexually transmitted diseases and immune compromise

The heterosexual transmission of subtype E human immunodeficiency virus type 1 (HIV-1) infection was evaluated in 467 couples in Thailand in whom the man was HIV-1 positive and the woman had no risk factors for HIV other than sex with her infected partner. At baseline, 216 (46.3%) of the 467 women were positive for HIV-1; prevalence of HIV among women was 52.2% when their male partners had CD4+ lymphocyte counts of <200 cells/microL, 45.9% in women whose partners had counts of 200-499 micro/L, and 39.2% in women whose partners had counts of >/=500/microL. Women were twice as likely to be HIV positive if their partners had a history of a sexually transmitted disease (STD); however, their HIV prevalence was 29% among couples who had no STD history. It appears that female partners of men infected with subtype E HIV-1 are at high risk of infection even when the man's CD4+ cell count is relatively high. A high rate of STDs may contribute significantly to this risk [corrected].

Gynaecological conditions associated with HIV infection in women who are partners of HIV-positive Thai blood donors

Women who were partners of HIV-positive blood donors were enrolled in a study of heterosexual HIV transmission between March 1992 and December 1996 and were interviewed and examined. Gynaecological conditions, including cervical dysplasia, human papillomavirus (HPV) infection, gonorrhoea, chlamydial infection, trichomoniasis, bacterial vaginosis, vaginal candidiasis and syphilis were assessed in addition to HIV status and CD4 level. Of 481 women enrolled, 224 (46.6%) were HIV seropositive. HIV-infected women were more likely to have abnormal vaginal discharge on physical examination (OR=2.6, P <0.01), HPV infection with a high-risk type (OR=6.9, P <0.01), and cervical dysplasia (OR=5.3, P <0.01). The prevalence of other gynaecological conditions detected at the enrolment visit did not differ by HIV status. History of prior STD (OR=2.0, P <0.01) was more common among HIV-infected women. The median CD4 count was 400 cells/microl among HIV-infected women. The prevalence of abnormal vaginal discharge and bacterial vaginosis increased significantly with decreasing CD4 count. The prevalence of ectopy, vaginal candidiasis, and cervical dysplasia increased with decreasing CD4 count, but these trends were not significant. We conclude that HIV-infected Thai women appear to have increased prevalences of abnormal vaginal discharge, squamous intraepithelial lesions and self-reported history of STD.

Reliability of self-reported sexual behavior in human immunodeficiency virus (HIV) concordant and discordant heterosexual couples in northern Thailand

A partner study was conducted in northern Thailand between March 1992 and June 1996 which included data that allowed an assessment of the reliability of self-reports of sexual behavior and contraceptive use among heterosexual couples. The authors enrolled 529 couples among whom all male subjects were human immunodeficiency virus (HIV) seropositive voluntary blood donors and their female sexual partners were either HIV infected (n=246) or HIV seronegative (n=283). The levels of agreement within couples were assessed for recency of last sexual intercourse, sexual activity in the prior year, and contraceptive practices. For HIV discordant couples, a prospective study was conducted to examine risk factors for HIV transmission, the primary goal of the study. This allowed assessment of reliability of inter-partner reports over 6-12 months. Overall, agreement among couples was good for common sexual practices, especially vaginal intercourse and time since last intercourse, but was lower for condom use. Anal and oral sex were infrequently reported by these couples and there was greater disagreement for the occurrence of these practices. Partner agreement for contraceptive histories was good to excellent. Prospective data showed less frequent intercourse and more condom use but reliability remained good. Common sexual practices may be reliable for both HIV concordant and discordant couples in studies estimating prevalent infection. Estimates of incident heterosexually transmitted HIV may be made with greater reliability by studies which include assessment of reports of risk behavior by each member of a couple than studies of individuals.

Risk factors for HIV-1 transmission from HIV-seropositive male blood donors to their regular female partners in northern Thailand

OBJECTIVE

To describe risks for HIV transmission from male blood donors to their regular female sex partners in Chiang Mai, Thailand.

DESIGN

Cross-sectional study.

METHODS

From March 1992 through September 1995, 405 HIV-seropositive male blood donors (index cases) and their regular female partners were enrolled in the study. Women with risk factors for HIV infection other than sexual contact with the index male were excluded. Couples were interviewed and examined; specimens were collected for laboratory analysis.

RESULTS

Overall, 46% of the 405 women enrolled were HIV-positive. Ninety-eight per cent of male index cases had a history of sex with a female prostitute; 1.5% reported always using condoms with their regular partner. History of sexually transmitted disease (STD) and swollen inguinal lymph nodes in the female partner were associated with an increased risk of HIV infection in the female. History in the female of genital herpes [odds ratio (OR), 3.46; 95% confidence interval (CI), 1.50-8.78], gonorrhea or chlamydia infection (OR, 2.71; 95% CI, 1.39-5.53), and stable relationship of longer than 24 months (OR, 2.28; 95% CI, 1.02-5.09) were associated with an increased risk of HIV infection in the female. Consistent condom use in the past 2 years (OR, 0.10; 95% CI, 0.01-0.79) was associated with a decreased risk of HIV infection in the female.

CONCLUSIONS

Married women in northern Thailand who appear otherwise to be at low risk for HIV infection may be exposed to this virus by their husbands. High rates of sex with commercial sex workers among men and low use of condoms within stable relationships may be important factors promoting the transmission of HIV in married couples. Programs to increase the regular use of condoms among married couples could be an important public health intervention to prevent transmission of HIV and other types of STD in northern Thailand.

The incidence of HIV-1 infections in village populations of northern Thailand

OBJECTIVES

To determine the age- and sex-specific prevalence of HIV-1 infection in a general ambulatory population in northern Thailand in 1990 and 1992, and the incidence of HIV-1 infections between 1990 and 1992.

DESIGN

Health fairs were held in five villages in Chiang Mai province in northern Thailand between December 1989 and January 1990 and again in January 1992. Participation of all village residents was encouraged. Villagers were offered testing for serological markers of hepatitis B virus (HBV) infection and free HBV vaccine was made available to susceptible individuals.

METHODS

Sera from the two surveys were linked and coded by demographic characteristics (age group and sex). Individual identifiers were removed and the sera tested for HIV-1 antibodies by enzyme-linked immunosorbent assay with Western blot confirmation.

RESULTS

In 1990, 21 out of 1161 (1.8%) individuals were HIV-1-seropositive; the infection rates were 3.3% in men and 0.5% in women. In 1992, 44 out of 956 (4.6%) individuals were HIV-1-seropositive. Among people included in both surveys the 2-year incidence was 2.0% in women and 4.1% in men (annual incidence, 1.0 and 2.05%, respectively); however, among men over the age of 14 years the 2-year incidence was 6.3%, whereas among women of this age the 2-year incidence was 1.8% (annual incidence, 3.15 and 0.9%, respectively). Among men, incident HIV-1 infections were common, even among those aged 50 years or more.

CONCLUSIONS

Infections with HIV-1 are disturbingly frequent and increasing among adult populations in semi-rural areas of northern Thailand. In order to contain further spread of the epidemic public-health strategies targeted to the general public, including those in rural areas, will be needed.

Studies of human leprosy lesions in situ using suction-induced blisters. 2. Cell changes and soluble interleukin 2 receptor (Tac peptide) in reversal reactions

To examine the pathogenesis of type 1 (reversal) reactions in leprosy, we studied cellular and soluble immunologic components of skin lesions in 10 patients with reactions, 24 active patients without reactions, and 33 control patients whose leprosy had been treated and cured. Cells and Tac-peptide levels were obtained from fluid aspirated from blisters induced by suction directly over representative skin lesions. During reversal reactions: a) the lesions contained an increased number and percentage of CD4+ (T-helper) cells; b) Tac-peptide levels were elevated in half of the lesions; c) the increases in Tac peptide and CD4+ cells were directly correlated; and d) systemic administration of corticosteroids appeared to cause a reduction in the intralesional CD4+ cell population. These findings were localized to the skin, and do not represent simple filtration of these components from the peripheral blood. We conclude that spontaneous lymphocyte activation in situ, primarily of CD4+ cells, is an important feature of reversal reactions, and may be an intermittent or cyclic phenomenon during the reaction. Findings in active patients without reactions are consistent with the hypothesis that differing states of immunologic equilibrium have been established in different portions of the leprosy spectrum. In reversal reactions we may, therefore, be examining immunologic processes set in motion when a pre-existing equilibrium has been upset by spontaneous, natural events. The mechanism of such spontaneous changes in immunity in leprosy is of considerable interest, not only to understand the reaction, but also to examine the underlying determinants of delayed-type hypersensitivity and cell-mediated immunity in leprosy and the potential for artificially manipulating these responses, as proposed with vaccines or immunotherapy.

Comparison of IgM, IgG and IgA responses to M.leprae specific antigens in leprosy

Antibodies of IgM, IgG and IgA classes against M.leprae specific antigens (PGL-I, ND-O-BSA, and NT-O-BSA) were determined in the sera of 80 leprosy patients (28 untreated, 34 treated lepromatous and 18 tuberculoid), 25 tuberculosis patients and 33 normal individuals of Northern Thailand. No strong distinction in reactivity could be found between the three antigens. The IgM antibody assay yielded more positive results than assays for IgG and IgA. It was found that the positivity rates of IgM antibodies to all three antigens were highest in untreated lepromatous leprosy (82%). In tuberculoid leprosy, the positivity rates of IgM, IgG and IgA to the antigens were more variable, ranging from 22 to 50 percent. Patients with tuberculosis and normal individuals did not produce IgM antibodies against the antigens. The results suggested that the determination of IgM against the three antigens is a more sensitive and specific test for active leprosy than those of IgG and IgA. The relationship between the duration of treatment and IgM antibody levels in lepromatous leprosy (LL) was studied. Untreated LL patients had significantly higher IgM and IgA antibody levels than treated patients. There was no difference in IgG antibody levels between the two groups, and the levels of both groups were higher than normal controls. Serial determination of IgM antibodies in 7 LL patients revealed that treatment was strongly associated with progressive decrease in IgM antibody levels against all three antigens.

Studies of human leprosy lesions in situ using suction-induced blisters. 1. Cellular components of new, uncomplicated lesions

The cellular contents of blisters induced by suction over new, uncomplicated leprosy lesions, and in the skin of cured, control patients, have been examined with enzyme- and immuno-histochemical staining over a period of 4 days. The total cellularity of the blisters varied over a wide range, not correlated with the type of leprosy. Mononuclear cells predominated at all times studied, with nearly equal percentages of monocytes and T lymphocytes. The T-helper: suppressor ratio was significantly greater in BT than in BL and LL lesions at 48 hr. Suction blisters offer a painless, quantitative, reproducible, multiple-sampling method for obtaining cells from the cutaneous infiltrates of leprosy for phenotyping or functional analysis.

A study of adrenal corticol function and its reserve activity in long-acting injectable contraceptive users

Adrenal function and its reserve capacity were studied in eighteen healthy non-lactating women who received depot-medroxyprogesterone acetate (DMPA: 9 subjects) and norethisterone enanthate (NET-EN: 9 subjects) as long-acting injectable contraceptives. Methodological assessments included: (i) morning fasting concentration of serum cortisol; (ii) diurnal variation of adrenal corticol activity as evidenced by cortisol concentration in serum samples taken at 0700 and 1600 hours; (iii) urinary free cortisol excretion; and (iv) cortisol response to insulin-induced hypoglycaemia. None of these assessments was significantly altered by contraceptive administration. This finding indicates that the subject's ability to release cortisol in response to a stressful situation, as well as to normal day-to-day activity, was not impaired by these contraceptive steroids.

The effects of long-acting injectable contraceptives on carbohydrate metabolism

Carbohydrate metabolism, as assessed by the intravenous glucose tolerance test (i.v.-GTT), was studied in 19 healthy, non-lactating women who received injectable contraceptives containing either medroxyprogesterone acetate (DMPA) (10 subjects) or norethisterone enanthate (Net-En) (9 subjects). Tests were made prior to treatment and at intervals over a period of 15 months thereafter. Results obtained indicate that carbohydrate metabolism is not impaired by either of the two progestogens, and neither pyruvate nor cortisol concentrations changed significantly over the period of observation. However, the insulin release in response to glucose loading underwent interesting alterations during treatment. These abnormalities returned promptly to normal after withdrawal of treatment.

Trichomonas vaginalis in a perinephric abscess. A case report

A patient with chronic vulvo-vaginitis due to Trichomonas vaginalis, and obstructive uropathy associated with renal calculi, developed a perinephric abscess following trauma incurred in a motorcycle accident. T. vaginalis was seen on smear and cultured from the purulent drainage from the perinephric abscess. Although T. vaginalis is commonly pathogenic only to the lower genito-urinary system, the upper urinary tract may very rarely be involved by ascending infection. If this protozoan spreads to extraluminal sites the inflammatory potential is marked, as has been found in animals with experimental infection. Examination of a fresh smear of pus may be critically important in the diagnosis of closed-space infections of unknown etiology.