Bulletin of the Pan American Health Organization最新文献

The case-control study reported here evaluated the protective effect of BCG vaccine against leprosy in São Paulo, Brazil. Seventy-eight patients under age 16 who had been diagnosed as having leprosy (cases) and 385 healthy individuals (controls) were selected and matched by sex, age, place of residence, and type of exposure to leprosy (intradomiciliary or extradomiciliary). The cases were drawn from an active patient registry and from a group of new leprosy cases treated at 50 health centers in the cities of Bauru and Ribeirão Preto in the state of São Paulo. In order to estimate the protective effect of BCG, the prevalences of BCG scars in cases and controls were compared. The presence of one or more scars was associated with an estimated protective efficacy of 90% (95% confidence interval: 78% to 96%). Stratified analysis by age group, sex, socioeconomic level, and clinical form of the disease revealed no significant differences in the protection provided by the vaccine. However, it seems clear that more data will be needed in order to accurately assess the true relevance of BCG for leprosy control programs.

The purpose of the study reported here was to compare the bactericidal effectiveness of tetracycline and co-trimoxazole (a combination of sulfamethoxazole and trimethoprim) in treating cholera. The study, an open-ended random trial using adult patients with cholera cases confirmed by stool culture, was carried out in March 1993 at the Cholera Treatment Unit (CTU) of the Hospital de Apoyo Departmental María Auxiliadora in Lima, Peru. A total of 107 subjects were divided into two groups (A and B). The 50 in Group A received 500 mg of tetracycline orally every 6 hours for 3 days; the 57 in Group B received co-trimoxazole (160 mg of trimethoprim and 800 mg of sulfamethoxazole) orally every 12 hours for 3 days. The two groups were comparable in terms of age, sex, duration of symptoms prior to hospital admission, time at which antibiotic treatment was initiated, and clinical evolution. Control stool cultures of specimens obtained after treatment showed Vibrio cholerae O-1 present in 2% of the Group A and 12.3% of the Group B patients, and also showed V. cholerae non-O-1 present in 2% of the Group A patients and 3.5% of the Group B patients. Overall, it was concluded that both therapeutic treatment regimens were effective and that the strains of V. cholerae observed in the southern sector of the city of Lima were still susceptible to both antibiotics.

To help learn about the recommendations made by Bolivian pharmacists dealing with diarrhea cases, 498 pharmacies in three Bolivian cities (Cochabamba, El Alto, and La Paz) were visited by female interviewers who indicated they were seeking treatment for a child with diarrhea. Ninety-eight of the Cochabamba pharmacies were also visited by a male interviewer who indicated he was suffering from diarrhea and was seeking treatment. In response, fewer than 2% of the pharmacists recommended using oral rehydration salts (ORS), increasing fluid intake, or consulting a physician. Most recommended antimicrobials, antidiarrheals, or some combination of the two. At 329 (66%) of the pharmacies, oral rehydration salts were unavailable, and those that did have such salts rarely offered them to customers. At the time of the survey, pharmacists were not integrated into the Bolivian National Health Secretariat's training program for control of diarrheal diseases. Steps have since been taken to resolve this matter.

This article presents the argument that because of several demonstrated advantages, milk fluoridation provides a valid alternative to water fluoridation when the latter is not possible. Extensive literature describing study of fluoride compounds administered with calcium-rich food, as well as clinical trials and laboratory experiments with fluoridated milk, have demonstrated its effectiveness in caries prevention. The main criticisms of milk fluoridation are decreased bioavailability of the fluoride, the cost and administrative burden involved, and (in some cases) lack of sound clinical conclusions regarding its preventive efficacy. These criticisms are reviewed in the light of evidence now available.

A study was made of the feeding history from birth to 1 month of age in a cohort of children born and residing in the city of Córdoba, Argentina, in 1993. The sample was divided into six social strata, in accordance with the occupation of the individual primarily responsible for family support. A total of 620 mothers were surveyed 1 month (mean = 31 days; SD = 1.2 days) following delivery in order to obtain information on the occupational, housing, and demographic characteristics of the family. In addition, information was collected on the first food given to infants following birth as well as on the type of food received at 1 month of age, the latter being based on 24-hour recall. The living conditions and demographic characteristics of the families were associated with their social strata. Families in Stratum I (high) and strata II and III (intermediate) tended to have higher standards of living and to have parents who were older when the children were born than did families in the lowest strata (V and VI), while families in Stratum IV tended to approach the average values found for the entire sample. With regard to feeding practices, it was found that 98% of the children had begun breast-feeding during the first week of life. A statistical association was observed between first food and social strata, with breast-feeding being more prevalent among the very low strata (V and VI) and use of bottle feeding being more prevalent in strata I and III. At 1 month of age, 26% of the sample was receiving complete natural breast-feeding, 60% was receiving partial natural breast-feeding, and 14% was being entirely bottle-fed. A significant association (P < 0.05) was observed between type of breast-feeding and social strata, with a figure of 38% complete natural breast-feeding recorded for Stratum I as compared to 16% for Stratum IV and 17% for Stratum V. Other findings of this study that stood out were that a high percentage of children in all the strata were initially breast-fed; a high percentage of the children were given breast-milk substitutes during the first month of life; and a low prevalence of complete natural breast-feeding was observed at 1 month of age.

A survey conducted between September 1991 and August 1992 approached 800 physicians in two marginal areas of the cities of Lima and Chimbote, Peru. Among other things, the survey sought data about information sources influencing the drug prescription practices of Peruvian physicians, about how these practices were modified by experience, and about the rationality of drug treatments prescribed for dealing with selected common ailments. Of the 800 physicians, 184 had already established themselves in private practice, 309 were recent medical school graduates, and 307 did not complete the survey questionnaire. The responses provided suggested that knowledge acquired in medical school had little influence on the prescribing habits of either the established physicians or the recent graduates. Over two-thirds of both groups (69.6% of the physicians in private practice and 79.9% of the recent medical school graduates) indicated that their primary source of drug information was medical literature. Overall, however, data from this and related studies suggest that while the medical school influence was limited, the role of medical literature was less powerful than the survey participants claimed-because advertising materials distributed by pharmaceutical companies appeared to constitute a key source of information, one that tended to promote irrational drug use.

Authorities at the University of Antioquia, Colombia, felt it would be advisable to institute a student orientation program aimed at preventing health problems resulting from risky sexual behavior related to new cultural trends. The purpose of the work reported in this article was to collect information on the existing situation and provide appropriate advice to the Health Division of the University Welfare Office. For this purpose a survey was conducted with the voluntary participation of 836 students enrolled in their final year of study. A survey form containing 45 questions designed to elicit demographic and sexual behavior data was self-administered anonymously by the participating students. Among the participants who were sexually active, 10.9% (17.2% of the men, 3.3% of the women) said they had contracted some variety of sexually transmitted disease (STD). The most common diagnoses were gonorrhea (42%), genital warts (23%), and genital herpes (19%). The risk of contracting STD was 4.2 times greater in those reporting sex with strangers; 3.4 times greater in those reporting four or more sexual partners; and 2.5 times greater in those reporting homosexual relations, as compared to students not practicing such behaviors. Some 28.4% of 790 survey respondents or their partners had been pregnant; 49% of these pregnancies had terminated in abortions, 77% of these being induced abortions. Only 51.3% of the survey participants reported customary use of contraceptives, those most frequently cited being condoms (by 32% of the users), pills (20%), the rhythm method (18%), and extravaginal ejaculation (17%). Generally speaking, it appears that participating students had received little sex education. To obtain information, they had turned primarily to friends and books. Those who said they had received adequate sex education at home participated somewhat less frequently in risky behaviors but appeared a little less apt to have used contraceptives and a little more apt to think that women should not seek satisfaction in their sexual relationships. It has been recommended that the university establish programs to augment student knowledge in this area, prevent STDs and unwanted pregnancies, and encourage responsible exercise of sexuality.

In January and February 1992, an assessment was conducted of the safety and immunogenicity of two doses of a new oral cholera vaccine prepared from the recombinant B subunit of the toxin and from killed whole cells (rBS/WC) in 1,165 individuals between the ages of 12 months and 64 years in Barranquilla, Colombia. This was a randomized, double-blind placebo-controlled study. Participants received two doses of either the vaccine or a placebo (killed Escherichia coli K12) over a two-week interval. Few symptoms were detected during the three days following administration of the initial dose and even fewer following the second. Sera obtained upon administration of the first dose and two weeks after administration of the second were tested for Vibrio cholerae 01 Inaba vibriocidal antibodies and antitoxins. Geometric mean titers (GMT) of vibriocidal antibodies were found to increase two-fold in subjects receiving the vaccine. In the paired samples taken from vaccinated subjects, two-fold or greater increases were observed in 44% and four-fold or greater increases were observed in 34%, as compared to similar increases in 9.2% and 2.2% of the sera taken from those receiving the placebo (P < 0.05). The GMTs of IgG and IgA antitoxins, as determined by ELISA, increased by factors of 4 and 3.2, respectively, in those receiving the vaccine, as compared to factors of 1.1 and 1.1 in those given the placebo (P < 0.001 for IgG, P < 0.01 for IgA). Approximately 80% of the paired samples from the vaccinated group showed an increase of both IgG and IgA antitoxins > or = 1.5, as compared to only about 20% of those in the placebo group (P < 0.000001). Belonging to the O blood group did not significantly affect the immune response. Children under age four tended to show a weaker vibriocidal antibody response and a stronger antitoxin response than older subjects. The two doses of oral vaccine were found to be safe and without attributable side-effects. The vibriocidal antibody and antitoxin responses were similar to those obtained previously with the conventional oral killed whole cell B subunit cholera vaccine.