Long-term transmission patterns and public health policies leading to malaria elimination in Panamá

Abstract

Background: The present study provides a countrywide perspective of the malaria situation in Panamá over a longterm framework, with the purpose of identifying historical malaria resurgence events and their potential causes. Methods: A descriptive-ecological study was conducted by analysing demographic and epidemiological annual malaria time series data in Panamá (1884-2019) using several data sources. Malaria intensity indicators were calculated during the study period. The effects of El Niño Southern Oscillation on malaria transmission were also analysed using a retrospective analysis of malaria cases between 1957 and 2019. Results: Several factors were identified responsible for malaria resurgence in Panamá, mostly related with Malaria Control Programme weakening. During the past 20 years (2000-2019) malaria has progressively increased in prevalence within indigenous settlements, with a predominance of male cases and a high proportion (15% of total cases) in children less than 5 years old. During this period, a significant and increasing proportion of the Plasmodium falciparum cases were imported. Retrospective analysis (1957-2019) evidenced that ENSO had a significant impact on malaria transmission dynamics in Panamá. Conclusions: Data analysis confirmed that although authorities have been successful in focalizing malaria transmission in the country, there are still neglected issues to be solved and important intercultural barriers that need to be addressed in order to achieve elimination of the disease by 2022. This information will be useful for targeting strategies by the National Malaria Elimination Programme.

Plasmodium vivax Genetic Diversity in Panama: Challenges for Malaria Elimination in Mesoamerica

“…Panama, located at the southern end of Mesoamerica ( Figure 1 ), has also regionally committed to eliminate malaria by 2021 [ 9 ]. During the past years, however, a relentless malaria burden has been observed in recognized endemic areas; a situation further complicated by the reestablishment of P. falciparum transmission in the eastern region of the country [ 10 ]. Moreover, indigenous populations account for more than 90% of local malaria cases [ 10 , 11 ].…”

“…During the past years, however, a relentless malaria burden has been observed in recognized endemic areas; a situation further complicated by the reestablishment of P. falciparum transmission in the eastern region of the country [ 10 ]. Moreover, indigenous populations account for more than 90% of local malaria cases [ 10 , 11 ]. Most of these indigenous populations (92%) live in extreme poverty, with significant higher rates of malnutrition, and infant and maternal mortality, especially when compared with the rest of the Panamanian population [ 9 , 10 , 11 , 12 , 13 ].…”

“…Moreover, indigenous populations account for more than 90% of local malaria cases [ 10 , 11 ]. Most of these indigenous populations (92%) live in extreme poverty, with significant higher rates of malnutrition, and infant and maternal mortality, especially when compared with the rest of the Panamanian population [ 9 , 10 , 11 , 12 , 13 ]. Panama is also a hotspot for the transit of economic migrants worldwide [ 14 ].…”

“…Panama is also a hotspot for the transit of economic migrants worldwide [ 14 ]. Recent studies have shown a growing number of imported malaria continuously entering from South America through the Darién Gap, an area across the Colombia and Panama border ( Figure 1 ) [ 10 , 15 ]. Plasmodium parasites isolated from these imported cases have shown a higher genetic diversity when compared with the genetic structure displayed by local cases [ 15 ].…”

“…The majority (95%) of the malaria cases registered in Panama since 2000 have been caused by P. vivax [ 10 ]. This fact suggests that an efficient elimination plan must include a comprehensive study of P. vivax biology considering the species peculiarities that hamper its control.…”