Abstract
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.
Highlights
Lymphatic Filariasis (LF) and Onchocerciasis are parasitic helminth diseases that constitute a serious public health issue in tropical regions [1]
Lymphatic Filariasis (LF) is caused by parasitic worms which live in the lymphatic system
Onchocerciasis and LF affect over 146 million people, and have been targeted for elimination as public health problems by the World Health Organisation, using mass drug administration (MDA)
Summary
Lymphatic Filariasis (LF) and Onchocerciasis are parasitic helminth diseases that constitute a serious public health issue in tropical regions [1]. As LF, onchocerciasis is a major human disease which affects an estimated 26 million people in 34 countries [1, 2] Both diseases have been targeted for elimination by the World Health Organisation (WHO), using mass drug administration (MDA) [1, 3]. The LF elimination program is based on annual mass administration of a single dose of diethylcarbamazine or ivermectin combined with albendazole [1, 4], while the onchocerciasis elimination program is based on mass administration of ivermectin only [1] Both medications are generally considered to be safe, individuals who are heavily co-infected with Loa loa parasites are at risk of developing severe, even fatal, adverse reactions to either drug [5,6,7,8]. This observation has led to a requirement that precautionary measures be implemented before roll-out of LF and onchocerciasis MDA to communities in Loa loa high-prevalence areas [9, 10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
