Epidemiologic characteristics of blood donors with antibody to human immunodeficiency virus: Thailand.

Of 782,190 volunteer blood donors in Bangkok and nearby areas, who were screened for infection with human immunodeficiency type 1 (HIV-1) from January 1988 through December 1992, 3,219 tested positive on both enzyme immuno assay and Western blot assay. The identification variables of the donor were collected. The majority of HIV seropositive blood donors were male. The average age (median) of HIV seropositive was 26-29 years all through 1988-2992. The prevalence of HIV seropositive in male donors was higher than that in females. HIV seropositivity was confirmed in blood donations from first-time male donors in this study during 1988-1992. This rate has increased progressively from 0.87/1,000 in 1988 to 15.95/1,000 in 1992 with much higher rates in repeat donors. The repeat male donors increased from 0.77/1,000 in 1988 to 5.26/1,000 in 1991 and since then showed a decreased rate to 3.93/1,000 in 1992. Female donors were infected with HIV more frequently with the prevalence by sex ratio M:F rising from 27:1 in 1988 to 6.6:1 in 1992. Comparing the seropositive rate between first time and repeat female donors, the results showed an increase in rate from 0.11/1,000 in 1990 to 2.02/1,000 in 1992, but essentially the same rate in report donors. A majority of HIV seropositive blood donors (1990-1992) lived in Bangkok (42-49%) and among those who lived in one eastern province (Samut Prakan), 90-93% lived in the industrial areas. Of those who lived in Chon Buri Province, 73-88% lived in Sattaheep District, which is a naval base.

Prediction of low birth weight outcome in Thailand: multiple regression analysis.

In the present study the risk approach using maternal risk factors for LBW newborns in Thailand is applied. The study may be considered as a managerial tool for developing local strategies and is particularly useful in maternal and child health care. The main objective is to develop a model to predict LBW outcome with an aim to screen those at risk at the level of health centres, district and provincial hospitals. Using MLR analysis, it is concluded that Model I and Model II (Table 3 and 4) can be used to predict which pregnant women are likely to deliver LBW newborns. The prediction can be made as early as the first trimester. If the prediction is shown to be accurate, the two models will be very helpful for use in Thai people. For general use, the investigators believe that Model I will be appropriate for application at the level of provincial and district hospitals, while Model II should be used at the health centre level peripheral to the health delivery system.

Maternal risk factors for low birth weight newborn in Thailand.

The present study assesses the risk approach for maternal risk factors for LBW newborn in Thailand. This study can be considered as a managerial tool for developing local strategies and is particularly useful in the field of maternal and child health care. A summary of maternal risk factors for LBW newborn as listed in Table 7 and can be used as a health educational tool for pregnant women and as basic data for marital counseling. It can also be used to keep the public informed about the maternal risk factors for LBW newborn which will help Thai women of reproductive age avoid the chance of having such babies.

Risk factors for hepatitis B carrier status among blood donors of the National Blood Center, Thai Red Cross Society.

A study of risk factors for hepatitis B carriers among voluntary blood donors of the National Blood Center, Thai Red Cross Society was carried out in a case-control study design during January 1989 to June 1990. Cases were 876 blood donors whose blood identified HBsAg at time of recruitment and continued positive for more than 6 months. Controls were 1,750 blood donors whose blood was free from HBsAg who came for blood donation at the same period as the cases. The ratio of cases:controls = 1:2. Self-administered questionnaires were constructed and pretested before using both cases and controls. The study revealed that the risk factors for hepatitis B among voluntary blood donors were age of less than 30 years old; low socioeconomic status (family income of less than 8,000 Baht/month); single status, especially males; male occupations of students, monks, nongovernment workers compared with government officials; female occupations of laborers, students, nongovernment workers and government officials compared with housewives. Sharing of nail clippers, used blades and tooth brushes among family members are proved to be risk factors, especially among males. In addition, sharing of used blades in barber shops proved to be a risk among males while sharing of nail clippers in beauty salons, history of ear-piercing at department stores or history of caesarean section among females could not be shown to be risk factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Studies of immune response to hepatitis B vaccine in Thai blood donors.

The immunogenicity of heat-inactivated plasma derived hepatitis B vaccines were studied in one hundred and eighty-two adult blood donor volunteers whose HBV markers (HBsAg, anti-HBs) were negative. They were randomized for four regimens of 3 micrograms intramuscular Hepaccine-B vaccine at the schedules of 0, 1, 2, 9 months, 0, 1, 3, 9 months, 0, 2, 6, 12 months, 0, 1, 6, 12 months and another regimen of 5 micrograms Hevac-B Pasteur vaccine at 0, 1, 2, 9 months. Blood specimens, tested for serological marker (anti-HBs), were drawn at 1, 3, 6, 9, 12 and 15 months following the initial injection. The outcome revealed that the Hepaccine-B vaccinated group in the schedules of 0, 2, 6, 12 and 0, 1, 6, 12 months yielded seroconversion rates of 48.7% and 56.8%, respectively one month after vaccination. After that, the immune response (anti-HBs titer) regularly increased every three months until it reached 100% with a geometric mean (GMT) of 135 and 130 mIU/ml respectively in the fifteenth month. Taking the Hepaccine-B and the Hevac-B Pasteur with the same schedule (0, 1, 2, 9 months) into consideration, we found that the former yielded the higher seroconversion rate, one month after the initial injection, which increased to the highest rate of 95.8% in the ninth month. After that it was steady until the fifteenth month with higher GMT (584 mIU/ml) than that of Hevac-B Pasteur (323 mIU/ml). The seroconversion rate of Hevac-B Pasteur in the first month was lower than that of Hepaccine-B but it yielded the highest rate of 100% in the sixth month. After that, it gradually decreased and again increased to 100% in the fifteenth month.