Fernando Zacarías

Sífilis materna y sífilis congénita en América Latina: un problema grave de solución sencilla

From the data submitted to the Pan American Health Organization (PAHO) by nationwide programs against sexually transmitted diseases (STD), HIV infection, and AIDS (2002), one can estimate the overall prevalence of syphilis among pregnant women to be 3.1% and to range from 1.00% in Peru to 6.21% in Paraguay. According to these data, the incidence of congenital syphilis ranges from 1.4 per 1000 live births in El Salvador to 12.0 per 1000 live births in Honduras. Among men who engage in sex with other men, who often classify themselves as heterosexual, as well as in female sex workers, the prevalence of syphilis ranged from 5% to 15%. Factors that determine the persistence of congenital syphilis as public health problem include a lack of awareness of the seriousness of the problem among politicians, health officials, and health care providers, difficult access to prenatal care, and screening services, a low demand for the test among users, and the stigma and discrimination that surround sexually transmitted diseases (STD). This paper seeks to focus the attention of health professionals on maternal and congenital syphilis so they will undertake actions, using an interprogrammatic approach, to eliminate congenital syphilis from Latin America and the Caribbean. Eliminating congenital syphilis will only become possible if interventions targeting vulnerable groups are also implemented. PAHOs role in eliminating congenital syphilis includes determining the baseline situation in the Region as a whole and in each country, developing communication and procurement strategies, supporting nationwide programs, promoting operational research, and facilitating interprogrammatic coordination.

AIDS in the Americas: a public health priority for the region.

156 countries have reported over 250,000 AIDS cases to the WHO. Taking underreporting into account in developing countries, this figure grows to over 600,000 with 300,000 deaths. HIV-1 infection rates are estimated at between 5-10 million people. Projections indicate that there will be 5 million AIDS cases by 2000. AIDS is an unprecedented health problem that has enormous social, political, medical, and economic implications. The Americas account for 61% of the total cases reported to the WHO. Of the 46 countries in the Americas there have been 153,720 cases reported as of May 1, 1990. 96% of these cases were reported in the US, Brazil, Canada, Haiti, and Mexico. The geographic distribution of AIDS is not homogeneous because of a variety of factors. It was not introduced simultaneously in all countries; some were exposed later than others. Some countries have better detection systems. Excluding North America, the English-speaking Caribbean countries account for only 2% of the population, while the Latin Caribbean countries have 6%, yet they have 10% and 21% of the cases, respectively. Sexual transmission patterns reveal that bisexual men are the largest bridge between the homosexual and heterosexual community, not IV drug users. Studies show that blood donors who are paid are 18 times more likely to be HIV-1 positive in some areas. As AIDS prevalence increases in the heterosexual community, the rate of perinatal transmission also increases. This in turn increases the infant mortality rate because of increases in pediatric AIDS cases. Pediatric cases currently threaten much of the progress that has been made in developing countries in lowering the infant mortality rate. If this pandemic is to be stopped, prevention efforts must be increased as well as a shift in resources at the local, national, and global levels to find some effective method of containment.

Estimating HIV/AIDS prevalence in countries with low-level and concentrated epidemics: the example of Honduras.

Estimates of HIV/AIDS prevalence are important, because they are the primary measure of the current state of the epidemic in a country. How estimates of HIV/AIDS are made depends on the level of the epidemic. For estimates of HIV/AIDS prevalence in low-level and concentrated epidemics it is necessary to disaggregate the total adult population into sub-groups based on the relative risk of infection. For each group, the major issues and questions are: identifying risk groups, estimating the size of the populations, and estimating HIV prevalence in these groups. The greatest difficulty in making estimates of prevalence in low-level and concentrated epidemics is often establishing the size of various populations. Because of the uncertainty inherent in making an estimate of population size for these groups at high risk, low and high estimates are used. In order to demonstrate the method the case of Honduras was used. The most recent HIV prevalence data and the estimates of population sizes were applied. It was estimated that Honduras, which has a total population of 6,575,000 (United Nations Population Division sources), has approximately 55,000 adults living with HIV/AIDS, with a range of uncertainty between 30,000 and 80,000. Estimations of the burden of HIV is a continuous process and should be updated on a regular basis according to the most recent and relevant information available.

Análisis de la participación en encuestas de cinco países: relevancia para la investigación en salud pública

This study compares participation rates and reasons for nonresponse in surveys conducted in five countries of Latin America and the Caribbean. The objective of the surveys was to measure the prevalence of risk behaviors affecting the transmission of human immunodeficiency virus. The surveys were based on probability samples of the population of both sexes between 15 and 49 years old, except in Mexico, where only men were included. Proportions of three components of participation were estimated: residences interviewed, interviewed residences with eligible persons, and eligible persons who completed the interview. In addition, an overall index that combined the three components was calculated. The overall response rate ranged from 35.6% in Mexico to 81.4% in Chile. The component with the greatest variability was the participation of eligible persons, which ranged from 50% in Mexico to 95% in Cuba. These values were lower than what had been expected, especially among men, and will serve to guide future surveys, since rejection rates higher than the ones expected in the protocol should be considered. The results make it possible to infer the validity of the prevalence estimates for the various observed risk behaviors. The results also establish a benchmark to calculate the sample size in future surveys and to improve research methodology.