Screening for adulticidal activity against Anopheles arabiensis in ten plants used as mosquito repellent in South Africa.

BACKGROUND: Due to the development of resistance to synthetic insecticides, adverse effects to human health, non-target organisms and the environment, there is an urgent need to develop new insecticides, which are effective, safe, biodegrable and target-specific. This study was undertaken to evaluate the adulticidal activity of 10 plants used traditionally as mosquito repellents in South Africa. METHODS: The dried plant materials were extracted with dichloromethane (DCM) and ethanol (EtOH). The extracts were evaluated for adulticidal activity against Anopheles arabiensis mosquitoes, a potent malaria vector in South Africa. Adult mortality was observed after 24 hours of exposure. RESULTS: All the extracts showed adulticidal activity. The highest activity was observed in both DCM and EtOH extracts of Aloe ferox leaves with 98 and 86% mosquito mortality, respectively. The DCM extract of A. ferox leaves was then subjected to a dose-dependent bioassay to determine the EC50 value. The extract exhibited an EC50 value of 4.92 mg/ml. CONCLUSION: The results of the present study showed that the DCM extract of A. ferox leaves may have the potential to be used as an insecticide against An. arabiensis. Further studies to isolate and identify active compounds are in progress.

A Systematic Review of Factors That Influence Parents' Views and Practices around Routine Childhood Vaccination in Africa: A Qualitative Evidence Synthesis.

A Cochrane review which explored the factors that influence caregivers' views and practices around routine childhood vaccines worldwide was conducted by Cooper and colleagues. After sampling 154 studies that met their inclusion criteria, the authors included 27 studies in their synthesis, of which 6 were from Africa. The aim of the current review was to synthesise all 27 studies conducted in Africa. We wanted to determine if the inclusion of additional African studies will change any of the themes, concepts or theory generated in the Cochrane review. Our review found that parents' views and practices regarding childhood vaccination in Africa were influenced by various factors, which we categorised into five themes, namely, ideas and practices surrounding health and illness (Theme 1); social communities and networks (Theme 2); political events, relations, and processes (Theme 3); lack of information or knowledge (Theme 4); and access-supply-demand interactions (Theme 5). All of the themes identified in our review were also identified in the Cochrane review except for one theme, which was lack of information or knowledge. This finding will help to promote vaccine acceptance and uptake in Africa by developing and implementing interventions tailored to address lack of knowledge and information around vaccines.

A Systematic Review of Interventions to Improve HPV Vaccination Coverage.

Human papillomavirus (HPV) infection is the most common sexually transmitted infection worldwide. Although most HPV infections are transient and asymptomatic, persistent infection with high-risk HPV types may results in diseases. Although there are currently three effective and safe prophylactic HPV vaccines that are used across the world, HPV vaccination coverage remains low. This review evaluates the effects of the interventions to improve HPV vaccination coverage. We searched the Cochrane Central Register of Controlled Trials, PubMed, Web of Science, Scopus, and the World Health Organization International Clinical Trials Registry Platform and checked the reference lists of relevant articles for eligible studies. Thirty-five studies met inclusion criteria. Our review found that various evaluated interventions have improved HPV vaccination coverage, including narrative education, outreach plus reminders, reminders, financial incentives plus reminders, brief motivational behavioral interventions, provider prompts, training, training plus assessment and feedback, consultation, funding, and multicomponent interventions. However, the evaluation of these intervention was conducted in high-income countries, mainly the United States of America. There is, therefore, a need for studies to evaluate the effect of these interventions in low-and middle-income countries, where there is a high burden of HPV and limited HPV vaccination programs.

A systematic review of immunogenicity, clinical efficacy and safety of human papillomavirus vaccines in people living with the human immunodeficiency virus.

The human papillomavirus (HPV) is the most prevalent sexually transmitted infection worldwide. People living with the human immunodeficiency virus (HIV) are at high risk of HPV infection. This systematic review evaluates the immunogenicity, clinical efficacy, and safety of prophylactic HPV vaccines in people living with HIV. We registered the protocol for this review in the International Prospective Register of Systematic Reviews (CRD42018109898) and prepared the review following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). Five randomized trials with 1042 participants are included in this review. One trial with 120 participants compared the bivalent HPV vaccine to placebo, three trials with 830 participants compared the quadrivalent vaccine to placebo, and another trial with 92 participants compared the quadrivalent to the bivalent vaccine. There was low to moderate certainty evidence suggesting that seroconversion was higher among participants in the vaccine arms compared to the placebo arms for both vaccines. In one study with very low certainty evidence, participants who received the bivalent vaccine had higher anti-HPV-18 geometric mean titers (GMTs) compared to those who received the quadrivalent vaccine, despite little difference in anti-HPV-16 GMTs between the two vaccines. There were no differences in the incident and persistent HPV infections in both groups. None of the studies reported data on the incidence of precancerous lesions, or cancer. There were no reports of serious adverse events following vaccination in any of the trials. None of the included studies assessed the effects of HPV vaccines in adolescents living with HIV. Very limited evidence suggests lower immunogenicity of HPV vaccines in HIV positive compared to HIV-negative people. Finally, the long-term effect of the HPV vaccine in the incidence of cervical precancerous lesions and cervical cancer needs to be monitored. There is an urgent need for more high-quality randomized controlled trials that can address these gaps.

Vector-control personnel's knowledge, perceptions and practices towards insecticides used for indoor residual spraying in Limpopo Province, South Africa.

BACKGROUND: Contradictory arguments regarding the benefits and harm of insecticides, especially DDT, have caused concerns in different societal circles, threatening to undermine the achievements of the indoor residual spraying (IRS) programme in South Africa. These concerns were exacerbated by the screening of a documentary on South African Broadcasting Corporation (SABC) Television with anti-DDT sentiments. Consequently, Limpopo Malaria Control Programme (LMCP) Management advocated for an investigation to determine the potential effect of such campaigns on vector-control personnel's knowledge and perceived effects of insecticides on human health, with a view to improving the educational materials designed for use in training vector-control personnel. METHODS: The study was a cross-sectional descriptive survey using a structured field-piloted questionnaire, administered to 233 randomly selected vector-control personnel. Ethical clearance was granted by the University of KwaZulu-Natal. Approval for the study was granted by the Department of Health, Limpopo. Participation in the study was voluntary and all respondents signed informed consent. Descriptive statistics were used to analyse the collected data. RESULTS: Most respondents (96.6%) had a positive perception of IRS as a method to control malaria. Despite their positive perception, 93.6% viewed IRS insecticides to be potentially harmful to the users. DDT was perceived to cause long-term reproductive and respiratory effects, whereas alpha-cypermethrin and deltamethrin were largely associated with skin irritation/itchiness and skin burn. Study participants were more worried about DDT's potential effects on their reproductive system, including poor sexual performance, decline in libido, miscarriage and bearing children with genetic defects. However, none reported personal experience of bearing a child with genetic defects or miscarriage.Most anti-insecticide messages, especially relating to DDT, emanated from sources external to the LMCP, mainly through radio (62%) and television (33.9%) and about 70% believed such messages. While most respondents preferred to work with a moderately itchy deltamethrin, DDT was admittedly the most effective insecticide. CONCLUSION: Vector-control personnel faced health and ethical dilemmas, in that, while they perceived insecticides used for IRS in Limpopo to be potentially harmful to the health of users, as purported through media, they also viewed IRS using insecticides to be effective in controlling malaria.