malERA: An updated research agenda for characterising the reservoir and measuring transmission in malaria elimination and eradication

Abstract

This paper summarises key advances in defining the infectious reservoir for malaria and the measurement of transmission for research and programmatic use since the Malaria Eradication Research Agenda (malERA) publication in 2011. Rapid and effective progress towards elimination requires an improved understanding of the sources of transmission as well as those at risk of infection. Characterising the transmission reservoir in different settings will enable the most appropriate choice, delivery, and evaluation of interventions. Since 2011, progress has been made in a number of areas. The extent of submicroscopic and asymptomatic infections is better understood, as are the biological parameters governing transmission of sexual stage parasites. Limitations of existing transmission measures have been documented, and proof-of-concept has been established for new innovative serological and molecular methods to better characterise transmission. Finally, there now exists a concerted effort towards the use of ensemble datasets across the spectrum of metrics, from passive and active sources, to develop more accurate risk maps of transmission. These can be used to better target interventions and effectively monitor progress toward elimination. The success of interventions depends not only on the level of endemicity but also on how rapidly or recently an area has undergone changes in transmission. Improved understanding of the biology of mosquito–human and human–mosquito transmission is needed particularly in low-endemic settings, where heterogeneity of infection is pronounced and local vector ecology is variable. New and improved measures of transmission need to be operationally feasible for the malaria programmes. Outputs from these research priorities should allow the development of a set of approaches (applicable to both research and control programmes) that address the unique challenges of measuring and monitoring transmission in near-elimination settings and defining the absence of transmission.

Analyzing the Local Epidemiological Profile of Malaria Transmission in the Brazilian Amazon Between 2010 and 2015

“…Notwithstanding, very low transmission might mask seasonal patterns, requiring improvements in surveillance 21 . As transmission declines, interventions should be adapted to the new malaria typology 22 . There are several municipalities with high transmission, whereas others nearby do not have high transmission.…”

Plasmodium vivax molecular diagnostics in community surveys: pitfalls and solutions

“…The usage of molecular diagnosis for understanding the reservoir of transmission and to guide interventions has been emphasized by many recent publications [ 41 – 45 ], but the epidemiological relevance of detecting submicroscopic P. vivax infections is not the primary focus of this publication.…”

Seasonal variations in Plasmodium falciparum parasite prevalence assessed by varying diagnostic tests in asymptomatic children in southern Ghana

“…However, to move towards malaria elimination, an accurate profile of malaria transmission dynamics and infecting parasite clones in different transmission settings are needed to inform the implementation of the aforementioned strategies [ 2 , 3 ]. Inadequate information on malaria transmission intensity in endemic areas is common [ 4 , 5 ], and has resulted in either under or over estimation of the true prevalence of Plasmodium infections within different communities [ 6 ]. Unfortunately, the true prevalence of Plasmodium falciparum ( P .…”