Stratifying malaria receptivity in Bangladesh using archived rapid diagnostic tests
- PDF / 1,640,819 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 36 Downloads / 221 Views
Malaria Journal Open Access
RESEARCH
Stratifying malaria receptivity in Bangladesh using archived rapid diagnostic tests André Barembaye Sagna1, Mohammad Golam Kibria2, Shamsun Naher3, Shayla Islam3, M. M. Aktaruzzaman4, Mohammad Shafiul Alam2 and Cristian Koepfli1*
Abstract Background: Surveillance of low-density infections and of exposure to vectors is crucial to understand where malaria elimination might be feasible, and where the risk of outbreaks is high. Archived rapid diagnostic tests (RDTs), used by national malaria control and elimination programs for clinical diagnosis, present a valuable, yet rarely used resource for in-depth studies on malaria epidemiology. Methods: 1022 RDTs from two sub-Districts in Bangladesh (Alikadam and Kamalganj) were screened by qPCR for low-density Plasmodium falciparum and Plasmodium vivax infections, and by ELISA for Anopheles salivary gland antibodies as a marker for exposure to vectors. Results: Concordance between RDT and qPCR was moderate. qPCR detected 31/1022 infections compared to 36/1022 diagnosed by RDT. Exposure to Anopheles was significantly higher in Kamalganj despite low transmission, which could be explained by low bed net use. Conclusions: Archived RDTs present a valuable source of antibodies for serological studies on exposure to vectors. In contrast, the benefit of screening archived RDTs to obtain a better estimate of clinical case numbers is moderate. Kamalganj could be prone to outbreaks. Keywords: Rapid diagnostic test, Plasmodium falciparum, Plasmodium vivax, Malaria, Transmission, Surveillance, Salivary biomarker, Anopheles Background In many countries, scaled up malaria control has resulted in reduced morbidity and mortality. Between 2000 and 2015, malaria incidence worldwide fell by 37%, malaria mortality by 60% [1], and an increasing number of countries now aim for malaria elimination. In recent years, however, progress in reducing transmission has stalled, with 228 million cases and 405,000 deaths reported in 2018 [2]. Rapid diagnosis and treatment of symptomatic individuals is critical, but parasite density in many individuals is below the limit of detection of microscopy or *Correspondence: [email protected] 1 Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556‑0369, USA Full list of author information is available at the end of the article
rapid diagnostic test (RDT) of around 100 parasites/μL blood. As a result, a large proportion of all infections among febrile individuals escape diagnosis [3, 4]. This limitation also challenges surveillance, that relies on accurate case numbers and prevalence estimates. In pre-elimination settings, surveillance is crucial to monitor the impact of control interventions and adapt strategies as needed. As alternative to case number routinely reported by health centres, molecular screening can be applied to screen for low-density infections, either among febrile patients, or among the general population to identify asymptomatic infections. Ideal
Data Loading...
