Health decision-makers working in Africa often need to act for millions of people over large geographical areas on little and uncertain information. Spatial statistical modelling and Bayesian inference have now been used to quantify the uncertainty in the predictions of a regional, environmental risk map for Loa loa (a map that is currently being used as an essential decision tool by the African Programme for Onchocerciasis Control). The methodology allows the expression of the probability that, given the data, a particular location does or does not exceed a predefined high-risk threshold for which a change in strategy for the delivery of the antihelmintic ivermectin is required.

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Lymphatic Filariasis and Onchocerciasis (river blindness) constitute pressing public health issues in tropical regions. Global elimination programs, involving mass drug administration (MDA), have been launched by the World Health Organisation. Although the drugs used are generally well tolerated, individuals who are highly co-infected with Loa loa are at risk of experiencing serious adverse events. Highly infected individuals are more likely to be found in communities with high prevalence. An understanding of the relationship between individual infection and population-level prevalence can therefore inform decisions on whether MDA can be safely administered in an endemic community. Based on Loa loa infection intensity data from individuals in Cameroon, the Republic of the Congo and the Democratic Republic of the Congo we develop a statistical model for the distribution of infection levels in communities. We then use this model to make predictive inferences regarding the proportion of individuals whose parasite count exceeds policy-relevant levels. In particular we show how to exploit the positive correlation between community-level prevalence and intensity of infection in order to predict the proportion of highly infected individuals in a community given only prevalence data from the community in question. The resulting prediction intervals are not substantially wider, and in some cases narrower, than the corresponding binomial confidence intervals obtained from data that include measurements of individual infection levels. Therefore the model developed here facilitates the estimation of the proportion of individuals highly infected with Loa loa using only estimated community level prevalence. It can be used to assess the risk of rolling out MDA in a specific community, or to guide policy decisions.

IntroductionEpilepsy associated stigma remains a main hindrance to epilepsy care, especially in developing countries. In Africa, anti-epileptic drugs are available, affordable and effective. As of now, no community survey on epilepsy awareness and attitudes has been reported from this area Cameroon with a reported high prevalence of epilepsy.MethodsTo contribute data to the elaboration of the National Epilepsy Control Programme, we carried out a cross-sectional descriptive community survey of 520 households. We had as main objective to obtain baseline data on the knowledge, attitudes and practice of adults towards epilepsy in rural Cameroon, and compare with existing data.ResultsMost respondents had heard or read about epilepsy, knew someone who had epilepsy and had seen someone having a seizure. The most frequently cited cause of epilepsy was witchcraft. Most subjects believed epilepsy is contagious. Epilepsy was a form of madness or insanity to 33.5% of them. Only 54.9% of respondents would meet a medical doctor for the treatment. Most respondents would not permit equal employment opportunities, association and child's marriage to someone with epilepsy. Age, female sex and level of education were associated to negative attitudes (p<0.001).ConclusionAdults in Fundong are very acquainted with epilepsy but have many erroneous beliefs about the condition. Their attitudes are generally negative. The National Epilepsy Programme must insist on modes of transmission, treatment options and first aid measures during epileptic seizures. The elderly (>50 years) and those without any formal education should be the main targets during health information, education and communication programmes.

Loiasis is a neglected disease that may have great social and economic impact in some endemic areas. This study was designed to update the geographical distribution of loiasis and assess the frequency and perceptions of the clinical signs of the disease in the Eastern province of Cameroon. The investigation covered 32 villages and involved 4146 respondents. Human infection with Loa loa was endemic in all the study villages but the prevalence of microfilaraemia generally decreased from south to north. All of the study villages had local names for eye worm and Calabar swellings that varied in meaning and among the various ethnic groups. The most common traditional treatment for eye worm was garlic or onion juice, which is dripped into the affected eye. The body sites that were most affected by Calabar swellings were the upper (30%) or lower (32%) limbs. The swellings were very painful (46%), mildly painful (28%) or painless (26%). Most respondents (94%) reported that the swellings itched. The prevalence of L. loa microfilaraemia in most of the study villages was >20%. These villages are clearly at risk of severe adverse events, with encephalopathy, following mass distribution of ivermectin. The prevalence of the main clinical manifestations of loiasis (i.e. eye worm and/or Calabar swellings) was twice that of detectable microfilaraemia.