No long-term excess mortality after measles infection : a community study from Senegal

Because measles immunization has been found in all studies to reduce mortality with more than the share of deaths attributed to acute measles, the authors examined mortality after measles infection in a study in a rural area of Senegal that included 6924 unimmunized children, of whom 1118 developped measles. Age-adjusted post-measles mortality was similar to the mortality of unvaccinated, uninfected children (mortality ratio (MR) = 1.04, 95% confidence interval (CI) 0.80-1.35). When controlling for source of infection, mortality rate was significantly different for children who contracted measles from a person outside the home (index cases vs. unvaccinated, uninfected MR = 0.27 95% CI 0.009-0.85) and for children infected at home (secondary cases vs. unvaccinated, uninfected MR = 1.10 95% CI 0.80-1.51). Hence, secondary cases had markedly higher long-term mortality than did index cases (MR = 4.13 95% CI 1.26-13.58). These estimates were essentially unchanged when the effects of season, period, separation from mother, size of community, and size of compound were investigated using a multivariate Cox regression model. The authors conclude that measles infection was not associated with increased mortality after the acute phase of infection and that index cases had lower mortality than uninfected, unvaccinated children. The reduction in mortality after measles immunization can therefore not be explained by the prevention of post-measles mortality

Investigating molecular basis of lambda-cyhalothrin resistance in an Anopheles funestus population from Senegal.

BACKGROUND Anopheles funestus is one of the major malaria vectors in tropical Africa, notably in Senegal. The highly anthropophilic and endophilic behaviours of this mosquito make it a good target for vector control operations through the use of insecticide treated nets, long-lasting insecticide nets and indoor residual spraying. However, little is known about patterns of resistance to insecticides and the underlying resistance mechanisms in field populations of this vector in Senegal. METHODS Here, we assessed the susceptibility status of An. funestus populations from Gankette Balla, located in northern Senegal and investigated the potential resistance mechanisms. RESULTS WHO bioassays indicated that An. funestus is resistant to lambda-cyhalothrin 0.05 % (74.64 % mortality), DDT 4 % (83.36 % mortality) and deltamethrin 0.05 % (88.53 % mortality). Suspected resistance was observed to permethrin 0.75 % (91.19 % mortality), bendiocarb 0.1 % (94.13 % mortality) and dieldrin 4 % (96.41 % mortality). However, this population is fully susceptible to malathion 5 % (100 % mortality) and fenitrothion 1 % (100 % mortality). The microarray and qRT-PCR analysis indicated that the lambda-cyhalothrin resistance in Gankette Balla is conferred by metabolic resistance mechanisms under the probable control of cytochrome P450 genes among which CYP6M7 is the most overexpressed. The absence of overexpression of the P450 gene, CYP6P9a, indicates that the resistance mechanism in Senegal is different to that observed in southern Africa. CONCLUSIONS This study represents the first report of pyrethroid and DDT resistance in An. funestus from Senegal and shows that resistance to insecticides is not only confined to An. gambiae as previously thought. Therefore, urgent action should be taken to manage the resistance in this species to ensure the continued effectiveness of malaria control

Child mortality following standard, medium or high titre measles immunization in West Africa

The World Health Organization (WHO) recommended the use of high titre measles vaccine in 1989. Subsequent long term follow-up of several trials yielded results suggesting higher mortality among children inoculated with medium and high titre vaccines compared to standard titre vaccines, although none of the individual trials found significant differences in mortality. Long term survival after standard, medium and high titre measles vaccines has been investigated in a combined analysis of all West African trials with mortality date. In trials from Guinea-Bissau, The Gambia and Senegal, children received medium or high titre vaccines from 4 months of age and were compared to control groups recruited at the same time later receiving standard titre vaccine from 9 months of age. All children were followed up to at least 3 years old. Combining trials of high titre vaccines showed higher mortality among the high titre group compared to the standard group : mortality ratio (MR) = 1.33 (95 % CI : 1.02-1.73). Mortality among recipients of medium titre vaccines was not different from that in the standard vaccine group, MR = 1.11 (95 % CI : 0.54-2,27). In a combined analysis by sex, the adjusted mortality ratios comparing high titre vaccine with standard vaccine were 1.86 ( 95 % CI : 1.28-2.70) for females and 0.91 ( 95 % CI : 0.61-1.35) for males. The trials were not designed to study long term mortality. Adjustments for several possible sources of bias did not alter the results. The combined analysis showed a decreased survival related to hith titre measles vaccine compared with standard titre vaccines, though solely among females. As a result of these studies from West Africa and a study from Haiti, WHO has recommended that high titre measles vaccine no longer be used. (Résumé d'auteur

Can the deployment of community health workers for the delivery of HIV services represent an effective and sustainable response to health workforce shortages? Results of a multicountry study

In countries severely affected by HIV/AIDS, shortages of health workers present a major obstacle to scaling up HIV services. Adopting a task shifting approach for the deployment of community health workers (CHWs) represents one strategy for rapid expansion of the health workforce. This study aimed to evaluate the contribution of CHWs with a focus on identifying the critical elements of an enabling environment that can ensure they provide quality services in a manner that is sustainable. The method of work included a collection of primary data in five countries: Brazil, Ethiopia, Malawi, Namibia, and Uganda. The findings show that delegation of specific tasks to cadres of CHWs with limited training can increase access to HIV services, particularly in rural areas and among underserved communities, and can improve the quality of care for HIV. There is also evidence that CHWs can make a significant contribution to the delivery of a wide range of other health services. The findings also show that certain conditions must be observed if CHWs are to contribute to well-functioning and sustainable service delivery. These conditions involve adequate systems integration with significant attention to: political will and commitment; collaborative planning; definition of scope of practice; selection and educational requirements; registration, licensure and certification; recruitment and deployment; adequate and sustainable remuneration; mentoring and supervision including referral system; career path and continuous education; performance evaluation; supply of equipment and commodities. The study concludes that, where there is the necessary support, the potential contribution of CHWs can be optimized and represents a valuable addition to the urgent expansion of human resources for health, and to universal coverage of HIV services

Evolution of the Ace-1 and Gste2 Mutations and Their Potential Impact on the Use of Carbamate and Organophosphates in IRS for Controlling Anopheles gambiae s.l., the Major Malaria Mosquito in Senegal

Widespread of insecticide resistance amongst the species of the Anopheles gambiae complex continues to threaten vector control in Senegal. In this study, we investigated the presence and evolution of the Ace-1 and Gste2 resistance genes in natural populations of Anopheles gambiae s.l., the main malaria vector in Senegal. Using historical samples collected from ten sentinel health districts, this study focused on three different years (2013, 2017, and 2018) marking the periods of shift between the main public health insecticides families (pyrethroids, carbamates, organophosphates) used in IRS to track back the evolutionary history of the resistance mutations on the Ace-1 and Gste2 loci. The results revealed the presence of four members of the Anopheles gambiae complex, with the predominance of An. arabiensis followed by An. gambiae, An. coluzzii, and An. gambiae-coluzzii hybrids. The Ace-1 mutation was only detected in An. gambiae and An. gambiae-coluzzii hybrids at low frequencies varying between 0.006 and 0.02, while the Gste2 mutation was found in all the species with a frequency ranging between 0.02 and 0.25. The Ace-1 and Gste2 genes were highly diversified with twenty-two and thirty-one different haplotypes, respectively. The neutrality tests on each gene indicated a negative Tajima's D, suggesting the abundance of rare alleles. The presence and spread of the Ace-1 and Gste2 resistance mutations represent a serious threat to of the effectiveness and the sustainability of IRS-based interventions using carbamates or organophosphates to manage the widespread pyrethroids resistance in Senegal. These data are of the highest importance to support the NMCP for evidence-based vector control interventions selection and targeting

Integrating a diabetes and hypertension case management package within primary health care: a mixed methods feasibility study in Bangladesh

Background: Almost three quarters of non-communicable disease (NCD) deaths, and 82% of premature NCD deaths, occur in low- and middle-income countries. Bangladesh has an estimated 7 million hypertensives and 10 million diabetics, and primary care is struggling to respond. Our aim was to develop and support implementation of a diabetes and hypertension case management package, and assess its appropriateness, feasibility and acceptability in two NCD clinics within two primary-care centres in Bangladesh. Methods: We used a convergent mixed methods design. We first assessed the level of appropriate hypertension and cardiovascular disease patient management, based on a composite outcome indicator using data from patients’ treatment cards. Appropriate management was primarily informed by International Diabetes Federation (IDF) and World Health Organisation (WHO) guidelines. We then performed qualitative in-depth interviews with doctors and patients to explain these quantitative findings and to understand the challenges to achieving appropriate patient management in the NCD clinics. Results: Eighty-one newly diagnosed patients were recruited. Over 3 months, 53.1% (95% CI 42.3% to 63.6%) of patients were appropriately managed. We found incomplete diagnosis (especially missing hypertension diagnosis alongside diabetes) and non-provision of follow-up appointments were the main causes of the relatively low level of appropriate management. We conducted interviews with 11 patients and 8 health professionals and found a shortage of human resources, reporting materials, available drugs and diagnostic equipment. This undermined patients’ willingness to attend clinics and doctors’ willingness to offer follow-ups. Hands-on skill-building training was valuable in increasing doctors’ competence for appropriate management, but was seen as a novel training method and faced constraints to implementation. Conclusions: A clinical guide, skill-based training and recording package can be implemented in routine primary care and can lead to appropriate management of around half of diabetic and hypertensive patients in a low-income country. However, considerable health systems challenges must be addressed before more patients can be managed appropriately

Evaluation of antibody response to Plasmodium falciparum in children according to exposure of Anopheles gambiae s.l or Anopheles funestus vectors

<p>Abstract</p> <p>Background</p> <p>In sub-Saharan areas, malaria transmission was mainly ensured by <it>Anopheles. gambiae </it>s.l. and <it>Anopheles. funestus </it>vectors. The immune response status to <it>Plasmodium falciparum </it>was evaluated in children living in two villages where malaria transmission was ensured by dissimilar species of <it>Anopheles </it>vectors (<it>An. funestus vs An. gambiae </it>s.l.).</p> <p>Methods</p> <p>A multi-disciplinary study was performed in villages located in Northern Senegal. Two villages were selected: Mboula village where transmission is strictly ensured by <it>An. gambiae </it>s.l. and Gankette Balla village which is exposed to several <it>Anopheles </it>species but where <it>An. funestus </it>is the only infected vector found. In each village, a cohort of 150 children aged from one to nine years was followed during one year and IgG response directed to schizont extract was determined by ELISA.</p> <p>Results</p> <p>Similar results of specific IgG responses according to age and <it>P. falciparum </it>infection were observed in both villages. Specific IgG response increased progressively from one-year to 5-year old children and then stayed high in children from five to nine years old. The children with <it>P. falciparum </it>infection had higher specific antibody responses compared to negative infection children, suggesting a strong relationship between production of specific antibodies and malaria transmission, rather than protective immunity. In contrast, higher variation of antibody levels according to malaria transmission periods were found in Mboula compared to Gankette Balla. In Mboula, the peak of malaria transmission was followed by a considerable increase in antibody levels, whereas low and constant anti-malaria IgG response was observed throughout the year in Gankette Balla.</p> <p>Conclusion</p> <p>This study shows that the development of anti-malaria antibody response was profoundly different according to areas where malaria exposure is dependent with different <it>Anopheles </it>species. These results are discussed according to i) the use of immunological tool for the evaluation of malaria transmission and ii) the influence of <it>Anopheles </it>vectors species on the regulation of antibody responses to <it>P. falciparum</it>.</p