RESUMO
BACKGROUND: There are limited data on the epidemiology of sexually transmitted infections (STI) and their contribution to adverse birth outcomes (ABO) in sub-Saharan Africa (SSA). We performed a case-control study to assess the prevalence of STI and their association with ABO among women attending Queen Elizabeth Central Hospital, Blantyre, Malawi. METHODS: A composite case definition for ABO included stillborn, preterm and low birthweight infants and infants admitted to neonatal intensive care unit within 24 hours of birth. Following recruitment of an infant with an ABO, the next born healthy infant was recruited as a control. Multiplex PCR for Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and Trichomonas vaginalis (TV) was performed on maternal vaginal swabs. HIV and syphilis status was determined on maternal and infant serum. For syphilis, we used combined treponemal/non-treponemal rapid point-of-care tests in parallel with rapid plasma reagin tests, PCR for Treponema pallidum and clinical parameters to diagnose and stage the infection. We compared STI positivity between cases and controls. RESULTS: We included 259 cases and 251 controls. Maternal prevalence of STI was 3.1%, 2.7% and 17.1% for NG, CT and TV, respectively. Maternal prevalence of untreated syphilis was 2.0% and 6.1% for early stage and late/unknown stage, respectively; prevalence of treated syphilis was 2.7%. The HIV prevalence was 16.5%. HIV infection significantly increased the odds for ABO (OR=3.31; 95% CI 1.10 to 9.91) as did NG positivity (OR=4.30; 95% CI 1.16 to 15.99). We observed higher rates of ABO among women with untreated maternal syphilis (early: OR=7.13; 95% CI 0.87 to 58.39, late/unknown stage: OR=1.43; 95% CI 0.65 to 3.15). Maternal TV and CT infections were not associated with ABO. CONCLUSION: STI prevalence among pregnant women in Malawi is comparable to other SSA countries. HIV, NG and untreated syphilis prevalence was higher among women with ABO compared with women with healthy infants.
RESUMO
BACKGROUND: Cryptosporidium is a gastrointestinal pathogen that presents a serious opportunistic infection in immunocompromised individuals including those living with human immunodeficiency syndrome. The CRYPTOFAZ trial, previously published, was conducted in Malawi to evaluate the efficacy of clofazimine in response to an unmet need for drugs to treat cryptosporidiosis in HIV populations. A combination of rapid diagnostic tests, ELISA, qPCR, and conventional sequencing were employed to detect Cryptosporidium in 586 individuals during pre-screening and monitor oocyst shedding and identify enteric co-pathogens in 22 enrolled/randomized participants during the in-patient period and follow-up visits. METHODOLOGY: Oocyst shedding as measured by qPCR was used to determine primary trial outcomes, however pathogen was detected even at trial days 41-55 in individuals randomized to either clofazimine or placebo arms of the study. Therefore, in this work we re-examine the trial outcomes and conclusions in light of data from the other diagnostics, particularly ELISA. ELISA data was normalized between experiments prior to comparison to qPCR. The amount of all identified enteric pathogens was examined to determine if co-pathogens other than Cryptosporidium were major causative agents to a participant's diarrhea. CONCLUSION: ELISA had higher sample-to-sample variability and proved to be equally or less sensitive than qPCR in detecting Cryptosporidium positive samples. Compared to qPCR, ELISA had equal or greater specificity in detecting Cryptosporidium negative samples. Sequencing identified several Cryptosporidium species including viatorum which has never been identified in Malawi and Southern Africa. In addition to Cryptosporidium, enterotoxigenic E. coli was also identified as a pathogen in diarrheagenic amounts in 4 out of 22 participants.