Impact of improved treatment of sexually transmitted diseases on HIV infection in rural Tanzania: randomised controlled trial

Sexually transmitted diseases control in developing countries

Sexually transmitted diseases (STDs) are a major public health problem now compounded by the advent of AIDS and HIV infection. The size of the problem represented by STDs and HIV is unknown however it is estimated that there are 333 million new cases of STD per annum and currently 15-20 million people infected worldwide with HIV. Control programmes for STDs must prevent the acquisition of STDs, their complications and sequelae and interrupt and reduce transmission. They can also reduce the incidence of HIV infection. Such programmes must place emphasis on health education, condom usage, altering health seeking behaviour and providing case management. The syndromic approach currently offers the most realistic, and cost effective, way in which to treat patients.

Genital chlamydial infection among women in Nicaragua: validity of direct fluorescent antibody testing, prevalence, risk factors and clinical manifestations

OBJECTIVE

To validate the performance of a direct fluorescence antibody (DFA) test and to determine the prevalence, risk factors and clinical manifestations of cervical chlamydia infection in different groups of women in Nicaragua.

STUDY POPULATION

926 women, 863 routine clinic attenders (mean age 27 years) and 63 sex workers (mean age 25 years) attending health centres in León, Corinto, Matagalpa and Bluefields.

METHODS

Cervical specimens were examined using the Syva MicroTrak test system with a cut-off of 10 or more elementary bodies (EBs). The DFA results were validated by a one-step polymerase chain reaction (PCR) assay. Discordant results were further examined in nested PCR assays directed at two different target genes. An interviewer-administered questionnaire and a standard gynaecological examination were completed.

RESULTS

Sensitivity of DFA was 80.1%, specificity 98.3%, and positive and negative predictive values 62.5% and 99.3%, respectively. Values were lower in locations where samples thawed because of electricity breaks and higher among sex workers. The majority of discordant results was confirmed as positive in nested PCR assays. Prevalence of cervical chlamydia infection based on positivity in DFA and/or PCR ranged from 2% among routine clinic attenders aged 35 years or older, to 8% among adolescent clinic attenders, and to 14% among sex workers. Among routine clinic attenders, young age (odds ratio [OR] 3.6, 95% confidence intervals [95% CI] 1.4-8.9 for women aged 15-19 years as compared with 1 in women 25 years of age or older) and use of oral contraceptives (OR 4.0, 95% CI 1.7-9.6) were the only statistically significant risk factors identified in multivariate logistic regression analysis. Presence of mucopurulent cervical discharge (OR 5.9, 95% CI 3.0-11.5) and presence of ectropion (OR 2.6, 95% CI 1.1-6.5) were the clinical signs independently associated with infection.

CONCLUSIONS

Our results indicate that the DFA test was sensitive and specific while the performance of the PCR assay depends on adequate storage of samples. Genital C trachomatis infection is a common health problem among women in Nicaragua. The wide implementation of syndromic STD management algorithms together with health education programmes aimed at young people is the most promising approach to control STD in Nicaragua.

Chlamydiae as pathogens: new species and new issues

The recognition of genital chlamydial infection as an important public health problem was made first by the recognition of its role in acute clinical syndromes, as well as in serious reproductive and ocular complications, and secondly by our awareness of its prevalence when diagnostic tests became widely accessible. The recent availability of effective single dose oral antimicrobial therapy and sensitive molecular amplification tests that allow the use of noninvasive specimens for diagnosis and screening is expected to have a major impact in reducing the prevalence of disease in the next decade. Clinical manifestations associated with Chlamydia pneumoniae infection continue to emerge beyond respiratory illness. In particular, its association with atherosclerosis deserves further investigation. Chlamydia pecorum, a pathogen of ruminants, was recently recognized as a new species. The continued application of molecular techniques will likely elucidate an expanding role for chlamydiae in human and animal diseases, delineate the phylogenetic relationships among chlamydial species and within the eubacteria domain, and provide tools for detection and control of chlamydial infections.

Decreasing HIV-1 seroprevalence in young adults in a rural Ugandan cohort

OBJECTIVE

To assess the trend in HIV-1 seroprevalence in an adult population in Uganda.

DESIGN

An observational cohort study with four year follow up.

SETTING

A cluster of 15 villages in rural Uganda.

SUBJECTS

All residents of the 15 villages--about 10,000 people.

MAIN OUTCOME MEASURE

Prevalence of HIV-1 infection as assessed by enzyme immunoassay.

RESULTS

During the five year period the overall standardised seroprevalence of HIV-1 showed little change; 8.2% in 1990, 7.6% in 1994. Among males aged 13-24 years the prevalence decreased from 3.4% to 1.0% (P for trend < 0.001); among females of the same age the corresponding values were 9.9% and 7.3%. The decrease was greatest in males aged 20-24 years and females aged 13-19 years.

CONCLUSION

This is the first report of a decline in HIV-1 prevalence among young adults in a general population in sub-Saharan Africa with high overall HIV-1 prevalence. It is too early to conclude that the epidemic in this population is in decline, but the results of this study should be reason for some cautious optimism and encourage the vigorous pursuit of AIDS control measures.