Elimination of Rhodnius prolixus in Central America

Abstract

Rhodnius prolixus is one of the main vectors of Trypanosoma cruzi, causative agent of Chagas disease. In Central America, it was first discovered in 1915 in El Salvador, from where it spread northwest to Guatemala and Mexico, and southeast to Nicaragua and Costa Rica, arriving also in Honduras in the late 1950s. Indoor residual spraying (IRS) by the antimalaria services of Costa Rica prevented its spread southwards, and similar IRS programmes appear to have eliminated it from El Salvador by the late 1970s. In 1997, by resolution of the Ministers of Health of the seven Central American countries, a multinational initiative against Chagas disease (IPCA) was launched with one of the specific objectives being the elimination of R. prolixus from the region. As a result, more and more infested areas were encountered, and progressively sprayed using an IRS strategy already deployed against Triatoma infestans in the southern cone countries of South America. In 2008, Guatemala became the first of these countries to be formally certified as free of Chagas disease transmission due to R. prolixus. The other infested countries have since been similarly certified, and none of these has reported the presence of R. prolixus since June 2010. Further surveillance is required, but current evidence suggests that R. prolixus may now been eliminated from throughout the mesoamerican region, with a corresponding decline in the incidence of T. cruzi infections.

Prevalence of Trypanosoma cruzi infection in blood donors in El Salvador between 2001 and 2011

“…Specifically, of the 4,871 triatomine bugs detected, 2,525 (51.8%) corresponded to T. dimidiata and 2,346 (48.2%) to R. prolixus; 19% of triatomines were infected with T. cruzi, and 28.9% were infected with either Trypanosoma rangeli or with both T. cruzi and T. rangeli [17]. However, R. prolixus was last detected in El Salvador in 1976 [18] and officially declared by the PAHO to have been eliminated from the country in 2010 [7][8][9].…”

“…In El Salvador, elimination of R. prolixus was confirmed officially in 2010 by the IPCA [7][8][9]. However, El Salvador continues to be regarded as a country highly endemic for Chagas disease, as the national estimated positive serology rate for T. cruzi among blood donors is higher than that in other endemic countries in Central America.…”

Non, la maladie de Chagas n’est pas le nouveau sida des Amériques !

“…Chaque jour pourtant, et cela depuis plusieurs dizaines d'années, ces travaux donnent lieu à une bonne douzaine de publications scientifiques de niveau international. De même, ne sont ni rappelées ni même citées les grandes initiatives régionales (INCOSUR pour les pays du Cône Sud, IPA pour les pays du Pacte andin, IPCA pour les pays d'Amérique centrale) prises successivement, sous l'égide de la PAHO, pour contrôler, voire éliminer, la transmission vectorielle [14,24,28,37]. Pourtant, grâce à ces initiatives, la prévalence de la maladie a été réduite en moins de 20 ans de plus de 50 % et son incidence de pratiquement 90 % [26].…”

Elimination of Rhodnius prolixus in El Salvador, Central America

“…In 2011, Honduras and Nicaragua were also in the process of eliminating the disease transmission due to this vector (Hashimoto & Schofield 2012). Despite the improvements regarding R. prolixus, the current situation for T. dimidiata, a native species found in all Central American countries in domestic, peridomestic habitats and even urban areas, presents a permanent challenge to the control strategy for Chagas disease in the area.…”