Prevalence and risks of soil transmitted helminths among Ethiopian school children: A cross-sectional study

Objective: To assess the prevalence and associated factors of soil transmitted helminths (STHs) among Endemata primary school in North West Ethiopia, 2021. Methods: A cross-sectional study with 195 school children was conducted from May to July 2021 at Endemata primary school. The study participants were selected by using systematic random sampling technique. Stool samples were processed via direct wet mount and formol-ether concentration techniques. Data was entered by Epi-Dara version 3.1 and data analysis was done using SPSS version 20.0. Variables were considered to be statistically significant if P<0.05 at 95% confidence level. Results: The overall prevalence of STHs was 10.8% (95% CI 7.1-16.0). The prevalence of Ascaris lumbricoides, hookworm and Trichuris trichiura were 5.6% (95% CI 3.1-9.9), 3.1% (95% CI 1.3- 6.7) and 2.1% (95% CI 0.6-5.3), respectively. Grade 1-4 students were more likely to get infected with STHs as compared to grade 5-8 students (adjusted OR 4.7, 95% CI 1.3-16.6). Students who did not have latrines at their home were at higher risk to develop STHs infection comparing with those who had latrine at their home (adjusted OR 5.0, 95% CI 1.7-15.2). Similarly, the school children who did not wear shoes were more likely to be infected by STH parasite than those who did it (adjusted OR 6.3, 95% CI 1.9-20.7). The odds of being infected by STH parasites in children who did not trim their fingernails were 4.9 as compared to those who did it (adjusted OR 4.9, 95% CI 1.5-15.7). Conclusions: The prevalence of STHs among Endemata primary school children was low. Student grade level, latrine availability, shoes wear and nail status were significantly associated with STHs infection. Therefore, we recommend policy makers and stakeholders to follow the integration of deworming with water, hygiene and sanitation as well as the consistent health education of school children to control and prevent STH infections.

Prevalence and risks of soil transmitted helminths among Ethiopian school children: A cross-sectional study

Objective: To assess the prevalence and associated factors of soil transmitted helminths (STHs) among Endemata primary school in North West Ethiopia, 2021. Methods: A cross-sectional study with 195 school children was conducted from May to July 2021 at Endemata primary school. The study participants were selected by using systematic random sampling technique. Stool samples were processed via direct wet mount and formol-ether concentration techniques. Data was entered by Epi-Dara version 3.1 and data analysis was done using SPSS version 20.0. Variables were considered to be statistically significant if P<0.05 at 95% confidence level. Results: The overall prevalence of STHs was 10.8% (95% CI 7.1-16.0). The prevalence of Ascaris lumbricoides, hookworm and Trichuris trichiura were 5.6% (95% CI 3.1-9.9), 3.1% (95% CI 1.3- 6.7) and 2.1% (95% CI 0.6-5.3), respectively. Grade 1-4 students were more likely to get infected with STHs as compared to grade 5-8 students (adjusted OR 4.7, 95% CI 1.3-16.6). Students who did not have latrines at their home were at higher risk to develop STHs infection comparing with those who had latrine at their home (adjusted OR 5.0, 95% CI 1.7-15.2). Similarly, the school children who did not wear shoes were more likely to be infected by STH parasite than those who did it (adjusted OR 6.3, 95% CI 1.9-20.7). The odds of being infected by STH parasites in children who did not trim their fingernails were 4.9 as compared to those who did it (adjusted OR 4.9, 95% CI 1.5-15.7). Conclusions: The prevalence of STHs among Endemata primary school children was low. Student grade level, latrine availability, shoes wear and nail status were significantly associated with STHs infection. Therefore, we recommend policy makers and stakeholders to follow the integration of deworming with water, hygiene and sanitation as well as the consistent health education of school children to control and prevent STH infections.

Candidatus Rickettsia hoogstraalii in Ethiopian Argas persicus ticks.

Ethiopian soft ticks Argas persicus, hard ticks including both Amblyomma variegatum and Rhipicephalus (Boophilus) spp., and fleas were collected from livestock, traditional human dwellings, and cracks and crevices of trees. They were assessed in pools for the presence of Rickettsia using PCR-based methods. The extracted tick DNA was subjected to molecular screening for Rickettsia, which revealed 50.5% of the pooled samples to be positive for Rickettsia spp. These were then subjected to multi-gene analysis using both outer surface proteins and housekeeping genes with proven discriminatory potential. Sequencing of the citrate synthase and outer membrane genes clearly led to the identification of three distinct rickettsial species, Candidatus Rickettsia hoogstraalii in Argas persicus ticks; R. africae in hard tick pools, and R. felis in fleas. Furthermore, we demonstrated the presence of the plasmid-borne small heat-shock protein gene hsp2 in DNA from A. persicus ticks suggesting that Candidatus R. hoogstraalii carried by these ticks possess a plasmid. Unlike chromosomal gene sequences, the hsp2 gene failed to cluster with Candidatus R. hoogstraalii, instead falling into an isolated separate clade, suggesting a different origin for the plasmid.

Borrelia in Ethiopian ticks.

Two regions (Jimma and Dire Dawa) in Ethiopia were investigated for the presence of soft ticks. Although no Ornithodoros spp. ticks were collected during this survey, published records of their existence in Ethiopia were found. An overwhelming infestation of Argas persicus was revealed in a village located adjacent to Dire Dawa. These ticks primarily were feeding on poultry, but were also biting humans. Furthermore, hard ticks were collected from livestock and companion animals in these regions. Collected ticks were assessed for Borrelia by real-time PCR followed by conventional PCR and sequencing to identify species present. A. persicus ticks were found to carry B. anserina in 3 of 40 (7.5%) A. persicus tick pools, whilst hard tick pools yielded 2 of 16 (12.5%) positive for B. theileri. Collectively, these borrelial species and their tick vectors are likely to have an important economic impact of particular relevance to subsistence farmers in Ethiopia.

Bartonella quintana in Ethiopian lice.

Head and clothing lice from Jimma, Ethiopia were investigated for pathogenic bacteria. Genomic DNA from pools of lice was subjected to PCR analysis for Bartonella spp., Borrelia spp. Coxiella burnetii, Rickettsia spp. and Yersinia pestis. All 102 lice pools were negative for the afore mentioned pathogens, with the exception of Bartonella species found among 6 of 65 (9.2%) head lice pools and1 of 33 clothing lice pools. Identification was achieved by sequencing the ribosomal intragenic transcribed spacer region (ITS), revealing all to be Bartonella quintana. Although established as a clothing louse-borne infection, typically causing chronic bacteraemia, trench fever, bacillary angiomatosis and endocarditis, this has only been rarely reported among head lice. The higher numbers of infected head lice pools compared with clothing lice suggests their competence for maintaining this infection within Ethiopia.

Epidemiology of nematode parasites of sheep around Jimma, southwestern Ethiopia.

An investigation was made into the epidemiology of nematode infections of sheep in two districts of Jimma zone, southwestern Ethiopia. We used two approaches--long-term monitoring of identified sheep for nematode infection and abattoir or market survey for analysis. In the first monitoring regime, we used 80 lambs [40 sheep (20 per sex) from each district (Dedo and Yebu)] averaging 4-5 months of age. Faecal egg counts (FEC), packed cell volume (PCV) and body weight changes were monitored over a period of 1 year. Additionally, faecal samples were collected (on a weekly basis) from sheep brought to abattoir/market for 1 year to monitor faecal egg counts. The nematode parasite burden, as judged by FEC and PCV, was generally low indicating that the climatic conditions are not conducive to the development and survival of nematode eggs and the free-living stages; hence, little transmission occurred. In the experimental flocks, the highest FEC and lower PCV were recorded during the long rainy season (June to September) with peak in August and September. Faecal samples collected from abattoir/market also followed the same trend. Results from experimental sheep indicated that location had a significant (P < 0.01) effect on FEC, PCV and average daily body weight gain. The FEC and PCV for sheep in Yebu (mid-altitude) district were 126 +/- 3.33 and 30.6 +/- 0.26, whereas the values for Dedo (highland) were 93 +/- 4.35 and 32.0 +/- 0.21, respectively. The results indicate that the highland areas are comparatively less favourable to the survival and development of nematodes. Female lambs had lower FEC and higher PCV compared to male lambs (P < 0.05). The overall nematode parasite challenge in the area, however, is low. We, therefore, recommend rotational grazing management combined with monitoring parasite load and selective treatment to reduce productivity loses and pasture contamination.