Could the bug Triatoma sherlocki be vectoring Chagas disease in small mining communities in Bahia,Brazil?

Searches for Chagas disease vectors were performed at the type locality from which Triatoma sherlocki Papa et al. (Hemiptera: Reduviidae: Triatominae) was described in the municipality of Gentio do Ouro, in the state of Bahia, Brazil, and in a small artisan quarry‐mining community ～13 km distant in a remote area of the same municipality. The latter site represents a new locality record for this species. Adults, nymphs and exuviae of T. sherlocki were found in 21% of human dwellings, indicating that the species is in the process of domiciliation. Prevalence of Trypanosoma cruzi infection in collected bugs was 10.8%. Simple predictive approaches based on environmental similarity were used to identify additional sites likely suitable for this species. The approach successfully predicted an additional five sites for the species in surrounding landscapes. Ecological and entomological indicators were combined to discuss whether this scenario likely represents an isolated case or an emerging public health problem.     

Efficiency of sulphur in garlic extract and non‐sulphur homeopathy in the control of the cattle tick Rhipicephalus (Boophilus) microplus

The objective of the present work was to evaluate the efficacy of a non‐sulphur‐based homeopathic preparation and a sulphur‐containing natural product derived from Allium sativum (Linnaeus) against infestation by the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae). A total of 24 crossbred calves (7 : 8 Holstein : Zebu), aged 6–8 months and maintained in individual stables under tick‐free conditions, were divided into three groups. Group 1 (control group) received no treatment; Group 2 was treated with 0.01 g/day of the homeopathic preparation Fator C&MC^®, and Group 3 was treated with 20 g/day of Enxofre‐Allium sativum^®. After adaptation to the diet for 1 month, each calf was subjected to artificial infestation with 8000 R. (B.) microplus larvae (aged 7–14 days) twice per week over a 5‐month period. Numbers of engorged females were recorded every 14 days and samples of freely released engorged females were collected at 14‐day intervals commencing 3 months after the start of the experiment. The engorged females were weighed, incubated for 15 days under biochemical oxygen demand conditions at 27 ± 1 °C and relative humidity >85%, and the weights of the egg masses produced were recorded. Other biological parameters, including reproduction estimate, reduction in oviposition and efficiency of treatment, were determined. A significant reduction in the number of engorged females was detected on animals treated with Enxofre‐Allium sativum^® (Group 3) in comparison with the other two groups. The overall efficiency of the treatment with the sulphur‐containing product was 64%, whereas that of the homeopathic preparation was 26%. Under the experimental conditions established, Enxofre‐Allium sativum^® can reduce the intensity of the R. (B.) microplus infestation.