Seroprevalence and risk factors for Trypanosoma evansi, the causative agent of surra, in the dromedary camel (Camelus dromedarius) population in Southeastern Algeria.

Surra, caused by Trypanosoma evansi, is a re-emerging animal trypanosomosis, which is of special concern for camel-rearing regions of Africa and Asia. Surra decreases milk yield, lessens animal body condition score and reduces market value of exported animals resulting in substantial economic losses. A cross-sectional seroprevalence study of dromedary camels was conducted in Algeria, and major risk factors associated with infection were identified by collecting data on animal characteristics and herd management practices. The seroprevalence of T. evansi infection was determined in sera of 865 camels from 82 herds located in eastern Algeria using an antibody test (card agglutination test for Trypanosomiasis - CATT/T. evansi). Individual and herd seroprevalence were 49.5% and 73.2%, respectively, indicating substantial exposure of camels to T. evansi in the four districts studied. Five significant risk factors for T. evansi hemoparasite infection were identified: geographical area, herd size, husbandry system, accessibility to natural water sources and type of watering. There was no association between breed, sex or age with T. evansi infection. Results of this study provide baseline information that will be useful for launching control programmes in the region and potentially elsewhere.

Human Health Risks Associated with Metals from Urban Soil and Road Dust in an Oilfield Area of Southeastern Algeria.

Hassi Messaoud town is a recent city that is situated inside the oil field, which hosts an important petroleum extraction field and refinery. Large-scale and long-term oil refinery and corresponding industrial activities may contaminate the surrounding soil/dust and could lead to pollution levels that can affect human health. The soil and road dust samples were analysed for different trace elements: copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn). Geo-accumulation index (I(geo)), pollution index (PI), and integrated pollution index (IPI) were calculated to evaluate the heavy metal contamination level of urban soil and road dust. The I(geo) values indicate unpolluted to moderate polluted of investigated metals in the soil samples. The assessment results of PI support the results of I(geo), and IPI indicates heavy metals in road dust polluted seriously. The noncarcinogenic health risk assessment shows that ingestion of soil/dust particles is the route for exposure to heavy metals, followed by dermal adsorption. The human exposure risk assessment based on different exposure pathways showed that the hazard index (HI) was <1.0 for all of the elements. The relative exposure risk (noncarcinogenic) was greater for toddlers. Although the overall risk was within the acceptable limit of 1.00, the HI of Pb from the soil (0.103) and road dust (0.132) was close to the threshold limits, which over the long-term may pose a health risk.