A Qualitative Study of Barriers to Effectiveness of Interventions to Prevent Mother-to-Child Transmission of HIV in Arba Minch, Ethiopia

Objectives. Despite the availability of services to prevent mother-to-child transmission (PMTCT) of HIV, socio-cultural, health system and operational factors constrain many pregnant women from accessing services or returning for followup thereby increasing the risk of vertical transmission of HIV to newborns. We highlight and describe unique contextual factors contributing to low utilization of PMTCT services in Arba-Minch, Ethiopia. Methods. Qualitative research design was utilized to obtain data through focus group discussions and in-depth interviews with antenatal clinic attendees, health workers health facilities in the study area. Results. Awareness of PMTCT services and knowledge of its benefits was nearly universal, although socioeconomic, cultural and health system factors, including stigma and desire to prevent knowledge of serostatus, impede access to and utilization of services. Health system factors—lack of appropriate followup mechanisms, inadequate access to ARV drugs and poorly equipped manpower also contribute to low utilization of services. Conclusion. Reducing mother-to-child transmission of HIV in sub-Saharan Africa will be more effective when unique contextual factors are identified and addressed. Effectiveness of PMTCT interventions rests on a well functioning health system that recognize the importance of social, economic, cultural contexts that HIV positive pregnant women live in

A Monoclonal Antibody to Bacillus anthracis Protective Antigen Defines a Neutralizing Epitope in Domain 1

Antibody (Ab) responses to Bacillus anthracis toxins are protective, but relatively few protective monoclonal antibodies (MAbs) have been reported. Protective antigen (PA) is essential for the action of B. anthracis lethal toxin (LeTx) and edema toxin. In this study, we generated two MAbs to PA, MAbs 7.5G and 10F4. These MAbs did not compete for binding to PA, consistent with specificities for different epitopes. The MAbs were tested for their ability to protect a monolayer of cultured macrophages against toxin-mediated cytotoxicity. MAb 7.5G, the most-neutralizing MAb, bound to domain 1 of PA and reduced LeTx toxicity in BALB/c mice. Remarkably, MAb 7.5G provided protection without blocking the binding of PA or lethal factor or the formation of the PA heptamer complex. However, MAb 7.5G slowed the proteolytic digestion of PA by furin in vitro, suggesting a potential mechanism for Ab-mediated protection. These observations indicate that some Abs to domain 1 can contribute to host protection