Revista de Saúde Pública
Print version ISSN 0034-8910
FORATTINI, Oswaldo Paulo et al. Ecological aspects of South American trypanosomiasis: XVII - The domiciliation development of local triatominae populations in the Triatoma sordida endemic center. Rev. Saúde Pública [online]. 1983, vol.17, n.3, pp. 159-199. ISSN 0034-8910. http://dx.doi.org/10.1590/S0034-89101983000300001.
The results of observations made on triatominae bug domiciliation, after house cleaning using chemical substances, are reported. The work was carried out during the period January 1975 to January 1979. The region studied is part of the endemic center formed by the "cerrados" (doy up-land forests) of Central Brazil. Original local bug domiciliation found before house treatment, was composed of Triatoma infestans and Triatoma sordida populations. After desinsectization, surveillance research showed the start and development of a new, thowgh slower, domiciliation procedure, leading to house infection rates well below those initially found. After house cleaning, these values varied from 1.9 to 5.7%, comparing with 40.4% in the initial survey. This situation continued for at least three and half years, suggesting strongly that the surveillance activities should be started at the end of this period. In the meantime efforts should be made to induce the local human population to co-operate in denouncing new intradomiciliary triatominae foci and to maintain the standard of home cleanliness, as high as possible. As for the transfer of trypanosomiasis infection to the home, it was shown to be mainly due to domiciliated or semidomiciliated vertebrates, principally rats (Rattus) and opossums (Didelphis), of ubiquitous behaviour. In the new domiciliation process, a predominant role was performed by T. sordida starting with the invasion of the peridomiciliary environment. The reappearance of T. infestans was due mainly to human activity. The role of R. neglectus was very small though like T. sordida, it readily established itself in experimental hen houses. The proportional participation of the two main species in the specific composition of domiciliated bug populations was considered before and after house cleaning, through the positive dwellings rates on five differents dates. Results showed a constant increase of T. sordida participation, and an equally constant decrease of that of T. infestans. The more intense T. infestans domiciliation process than that of T. sordida is attributable to educational and residence factors. There was evidence of active dispersal capacity of the T. infestans. In the rural areas peridomiciliary dwellings fulfilled the concentration ecotopes role for the domiciliation process starting with sylvatic triatominae bugs, mainly T. sordida. Areas with fever of these dwellings, seem to, resist re-infestation longer than others.
Keywords : Trypanosomiasis, South American; Triatoma sordida; Triatoma infestans; Rhodnius neglectus; Triatominae [domiciliation]; Triatominae [control]; Entomological surveillance; Ecology.