Medical DevicesFungi Pathogenic To Insects Are New Tool In Fight Against Chagas Disease
Entomopathogenic fungi may be a safe and efficient means of controlling
Triatoma infestans, the bug that helps spread Chagas disease, according to
new
research conducted in Argentina. The study, published May 12 in the
open-access journal PLoS Neglected Tropical Diseases, shows the success of
the
fungi to kill bugs resistant to current control methods.
Chagas disease is the most relevant parasitic disease in Latin America,
being a major burden that affects mostly poor human populations living in
rural areas. The parasite Trypanosoma cruzi is mainly transmitted through
blood-feeding triatomine bugs; in the southern Cone of South America the
most prominent vector is Triatoma infestans. Current control strategies
based on residual chemical insecticide application are threatened by the
emergence of pyrethroid resistance.
The researchers, led by Patricia Juç¡rez, performed both laboratory and
field experiments showing that the entomopathogenic fungus Beauveria
bassiana
is virulent against bug populations from pyrethroid-resistant foci in the
Argentina/Bolivia border. An attraction-infection trap was developed and
tested during a 15-day period in field assays performed in two rural
villages, demonstrating that more than 50% of the bugs detected were
killed by
fungal infection. By existing vector population models, the bug population
reduction was estimated to reduce the risk of acquiring the parasite
infection.
This approach might also prove useful at different settings, e.g.
peridomiciliary environments where current tactics and procedures are
reported to
fail, and rural communities located in remote areas inaccessible to
sanitary control teams. The authors emphasize that these results might
help to
provide a safe and efficient alternative to overcome bug
pyrethroid-resilience in the short term, and might be useful to control
other Chagas disease
vectors as well.
Financial Disclosure:
Partial financial support came from the Pan American
Health Organization/World Health Organization/Special Program for Research
and Training in Tropical Disease (A20433), the Agencia Nacional de
Promocion Cientifica y Tecnologica, Argentina (PICT 01-14174), and the
Consejo
Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Argentina,
to MPJ. The funders had no role in the study design, data collection and
analysis, decision to publish, or preparation of the manuscript.
Competing Interests:
NP, SJM, JRG, and MPJ have a patent pending on a
blood-sucking insect trap, and a method to detect and control those
insects.
Citation:
"Control of Pyrethroid-Resistant Chagas Disease Vectors with Entomopathogenic Fungi."
Pedrini N, Mijailovsky SJ, Girotti JR, Stariolo R, Cardozo RM, et al. (2009)
PLoS Negl Trop Dis 3(5): e434.doi:10.1371/journal.pntd.0000434
PLoS Neglected Tropical Diseases