Uncovering the Burden of Dengue in Africa: Considerations on Magnitude, Misdiagnosis, and Ancestry

Abstract

Dengue is a re-emerging neglected disease of major public health importance. This review highlights important considerations for dengue disease in Africa, including epidemiology and underestimation of disease burden in African countries, issues with malaria misdiagnosis and co-infections, and potential evidence of genetic protection from severe dengue disease in populations of African descent. The findings indicate that dengue virus prevalence in African countries and populations may be more widespread than reported data suggests, and that the Aedes mosquito vectors appear to be increasing in dissemination and number. Changes in climate, population, and plastic pollution are expected to worsen the dengue situation in Africa. Dengue misdiagnosis is also a problem in Africa, especially due to the typical non-specific clinical presentation of dengue leading to misdiagnosis as malaria. Finally, research suggests that a protective genetic component against severe dengue exists in African descent populations, but further studies should be conducted to strengthen this association in various populations, taking into consideration socioeconomic factors that may contribute to these findings. The main takeaway is that Africa should not be overlooked when it comes to dengue, and more attention and resources should be devoted to this disease in Africa.

Keywords: Aedes; Africa; ancestry; climate change; coinfection; dengue; epidemiology; misdiagnosis; mosquitoes; outbreaks.

Figure 1

PRISMA-like diagram outlining the methods for article screening.

Figure 2

Mapping the epidemiology of dengue in Africa [30,35]; see Table 1 references. Notes: In 2011, the Republic of South Sudan seceded from Sudan. Therefore, it is difficult to determine whether dengue and/or Aedes exist in both Sudan and South Sudan due to the recent split and a lack of updated data. Thus, while South Sudan is coded as “no data available” and remains colored white for this map, it is likely that in the past, when the two countries were still combined, dengue cases and/or transmission had occurred in what is now considered South Sudan based on geographic proximity to other dengue-endemic countries and environmental suitability. These results are based on recorded cases only. Not every country has surveillance systems in place for dengue, but transmission may be possible based on vector competence and geography, and transmission may be occurring unrecognizably.