Strongyloidiasis in Ethiopia: systematic review on risk factors, diagnosis, prevalence and clinical outcomes

Abstract

Background: Strongyloidiasis is a gastrointestinal infection caused by the parasitic nematode Strongyloides stercoralis. It is estimated to infect up to 370 million people globally and is predominately found in tropical and subtropical areas of socioeconomic disadvantage. Main body: This systematic literature review identified studies published in the last ten years on the risk factors, diagnosis, prevalence and/or clinical outcomes of strongyloidiasis in Ethiopia. The prevalence of S. stercoralis ranged from 0.2 to 11.1% in adults, 0.3% to 20.7% in children, 1.5% to 17.3% in HIV positive adults and 5% in HIV positive children. The identified studies primarily used microscopy based techniques that potentially underestimated the prevalence four fold compared with serology and PCR. Strongyloidiasis in children presents a particularly significant issue in Ethiopia as children often presented with anemia, which is associated with impaired mental and cognitive development. The most significant risk factor for strongyloidiasis was HIV status and although other risk factors were identified for helminth infections, none were statistically significant for S. stercoralis specifically. Several studies detected S. stercoralis in dogs and non-biting cyclorrhaphan flies. However, future research is needed to explore the role of these reservoirs in disease transmission. Conclusions: This review demonstrated that strongyloidiasis is an overlooked and neglected disease in Ethiopia. There is a need for a systematic approach using a combination of molecular and serology based diagnostic methods to ascertain the true incidence and burden of strongyloidiasis in Ethiopia. Further research is also needed to break the cycle of transmission by identifying environmental reservoirs, risk factors and exploring the potential for zoonotic transfer.

Strongyloidiasis in Africa: Systematic Review and Meta-Analysis on Prevalence, Diagnostic Methods, and Study Settings

“…The prevalence of strongyloidiasis among school children was 6.4% (6.0-6.8%) in this review. A considerable similar report among school-age children is also found in a systematic review conducted in Ethiopia [ 104 ]. This might be justified firstly by the fact that African children are living in unhygienic environment with poor sanitation practices where most children play with contaminated soil and walk barefoot that increases the probability of the entrance of the filariform larvae in the body [ 105 ].…”

Epidemiology of intestinal helminthiases in a rural community of Ethiopia: Is it time to expand control programs to include Strongyloides stercoralis and the entire community?

“…Even though data on the combination of techniques are not evaluated in this paper, the authors point out the fact that strongyloidiasis is underestimated Ethiopia and that there is a need to approach this issue through the use of a combination of diagnostic methods. [27]. The co-infection of hookworm and S. stercoralis in our sample was as expected: there is evidence in different geographic locations of similar patterns, as both parasites share the same transmission pathway [36,37].…”

“…To our knowledge, this is the first study carried out at community level specifically for the detection S. stercoralis in Ethiopia and this is the highest prevalence ever detected at the community level in the country. A very recent review of studies published in the last ten years on strongyloidiasis in Ethiopia [27] showed, a mean prevalence of 2.5% in healthy adults and 11% in HIV positive adults. In Africa, only a study carried out in Gabon showed a prevalence higher than our study, 91.8%, but it was in a population of 15 PSAC [28,29].…”

Strongyloides stercoralis infection in Ethiopia: systematic review and meta-analysis on prevalence and diagnostic methods

“…This situation forced the health institutions to employ DSM method for the diagnosis of Strongyloides infection. As a result, under diagnosis and underreporting of the true prevalence of S. stercoralis infection in Ethiopia is a major problem ( Terefe et al, 2019 ). Thus, the aim of this systematic review and meta-analysis was to provide an overview of the prevalence of Strongyloides infection by country and regional label and by diagnostic methods used in Ethiopia.…”