Strengthening global vaccine access for adolescents and adults.

Global immunization efforts to date have heavily focused on infants and children, with noted success on public health. Healthy adolescents and adults contribute to the economic growth and development of countries but efforts to ensure vaccine coverage for these groups receive inadequate global attention and resources. Emerging epidemics for a number of infectious diseases including Ebola, Zika, dengue, malaria and the continuing epidemics of tuberculosis and several sexually transmitted infections, including HIV, HPV and Hepatitis B, have high incidence and prevalence in adolescents and adults. New vaccines under development for these diseases and under-used vaccines such as for human papilloma virus will have the greatest health and economic impact in these populations. Global consensus, political will, policies, global and country infrastructure, and financing mechanisms are needed to accelerate access for the billions of adolescents and adults living under the threat of devastating infectious disease outbreaks and epidemics, especially in lower income countries. The global health community and countries cannot afford to delay planning for implementation of adolescent and adult vaccine programs that will potentially save millions of lives and strengthen global and national economies. The article examines this next challenge and suggests a research agenda and a framework for action to galvanize global and national policy decision-makers to begin preparations for future immunization challenges.

Empowering communities in combating river blindness and the role of NGOs: case studies from Cameroon, Mali, Nigeria, and Uganda.

The control of onchocerciasis is not only a major success story in global health, but also one of the best examples of the power of public-private partnership at the international level as well as at the national level. The onchocerciasis story is also a leading example of the contribution of a group of called Non-Governmental Development Organizations (NGDO) to operational research which resulted in important changes in treatment strategies and policies.The four case studies presented here illustrate some key contributions the NGDOs made to the development of "community directed treatment with ivermectin" -CDTI, in Africa, which became the approved methodology within the African Programme for Onchocerciasis Control (APOC). The partnership between the international, multilateral, government institutions and the NGDO Coordination Group was the backbone of the APOC programme's structure and facilitated progress and scale-up of treatment programmes. Contributions included piloting community-based methodology in Mali and Nigeria; research, collaboration and coordination on treatment strategies and policies, coalition building, capacity building of national health workforce and advocacy at the national and international level. While the Onchocerciasis Control Programme (OCP) and APOC provided leadership, the NGDOs working with the national health authorities played a major role in advocacy evolving the community methodology which led to achieving and maintaining- treatments with ivermectin for at least 20 years and strengthening community health systems.

Epilepsy in onchocerciasis endemic areas: systematic review and meta-analysis of population-based surveys.

OBJECTIVE: We sought to evaluate the relationship between onchocerciasis prevalence and that of epilepsy using available data collected at community level. DESIGN: We conducted a systematic review and meta-regression of available data. DATA SOURCES: Electronic and paper records on subject area ever produced up to February 2008. REVIEW METHODS: We searched for population-based studies reporting on the prevalence of epilepsy in communities for which onchocerciasis prevalence was available or could be estimated. Two authors independently assessed eligibility and study quality and extracted data. The estimation of point prevalence of onchocerciasis was standardized across studies using appropriate correction factors. Variation in epilepsy prevalence was then analyzed as a function of onchocerciasis endemicity using random-effect logistic models. RESULTS: Eight studies from west (Benin and Nigeria), central (Cameroon and Central African Republic) and east Africa (Uganda, Tanzania and Burundi) met the criteria for inclusion and analysis. Ninety-one communities with a total population of 79,270 individuals screened for epilepsy were included in the analysis. The prevalence of epilepsy ranged from 0 to 8.7% whereas that of onchocerciasis ranged from 5.2 to 100%. Variation in epilepsy prevalence was consistent with a logistic function of onchocerciasis prevalence, with epilepsy prevalence being increased, on average, by 0.4% for each 10% increase in onchocerciasis prevalence. CONCLUSION: These results give further evidence that onchocerciasis is associated with epilepsy and that the disease burden of onchocerciasis might have to be re-estimated by taking into account this relationship.

Variation in incidence of serious adverse events after onchocerciasis treatment with ivermectin in areas of Cameroon co-endemic for loiasis.

OBJECTIVE: To determine the incidence of serious adverse events (SAEs) after mass treatment with ivermectin in areas co-endemic for loiasis and onchocerciasis, and to identify potential risk factors associated with the development of these SAEs, in particular encephalopathic SAEs. METHODS: We retrospectively analysed SAEs reported to have occurred between 1 December 1998 and 30 November 1999 in central-southern Cameroon by chart review, interview and examination of a subset of patients. RESULTS: The overall incidence of SAEs for the three provinces studied was 6 per 100,000. However, for Central Province alone the incidence of SAEs was 2.7 per 10,000 overall, and 1.9 per 10,000 for encephalopathic SAEs associated with Loa loa microfilaremia (PLERM). The corresponding rates for the most severely affected district within Central Province (Okola) were 10.5 per 10,000 and 9.2 per 10,000 respectively. Symptoms began within the first 24-48 h of ivermectin administration but there was a delay of approximately 48-84 h in seeking help after the onset of symptoms. First-time exposure to ivermectin was associated with development of PLERM. CONCLUSION: In Cameroon, the incidence of SAEs following ivermectin administration in general, and PLERM cases in particular, varies substantially by district within the areas co-endemic for loiasis and onchocerciasis. More intense surveillance and monitoring in the first 2 days after mass distribution in ivermectin-naïve populations would assist in early recognition, referral and management of these cases. The increased reporting of SAEs from Okola is unexpected and warrants further investigation. Research is urgently needed to find a reliable screening tool to exclude individuals (rather than communities) at risk of PLERM from the mass treatment program.