Por Nuno Sepúlveda (London School of Hygiene and Tropical Medicine & CEAUL).
Malaria elimination is currently on the agenda of more than 30 countries worldwide. This agenda brings unprecedented epidemiological challenges on how to accurately measure ongoing transmission. On the one hand, epidemiological measures based on the detection of infection might be uninformative due to the high probability of not sampling any infected individual in surveillance studies. Moreover, countries like Ethiopia, Eritrea or Peru are currently facing problems of detecting an increasing number of malaria cases infected with Plasmodium falciparum parasites lacking the histidine-rich protein-2 (pfHRP2) gene, whose protein product is on the basis of most popular rapid diagnostic tests. On the other hand, sero-epidemiological studies based on antibody data are gaining popularity among the scientific community, because they aim to estimate parasite exposure rather than infection. However, current statistical methods for the corresponding data analysis shows some limitations due to the use of (i) biased estimators for estimating key sero-epidemiological parameters, (ii) of simplified model assumptions for the data, and (iii) of study designs with reduced epidemiological power. This talk will present a global meta-analysis of the available data about the prevalence of pfHRP2 deletions and the respective association with other relevant genes for malaria diagnostics. It will also discuss some simple solutions for increasing the statistical reliability of future sero-epidemiological studies.
