Rat Ectoparasite Surveys in Puerto Rico with Toxicological Studies on Xenopsylla Cheopis

Irving Fox School of Medicine, School of Tropical Medicine, San Juan, Puerto Rico

Search for other papers by Irving Fox in
Current site
Google Scholar
PubMed Close
,
Ileana G. Bayona School of Medicine, School of Tropical Medicine, San Juan, Puerto Rico

Search for other papers by Ileana G. Bayona in
Current site
Google Scholar
PubMed Close
, and
Gisela A. Rivera School of Medicine, School of Tropical Medicine, San Juan, Puerto Rico

Search for other papers by Gisela A. Rivera in
Current site
Google Scholar
PubMed Close
DOI:
https://doi.org/10.4269/ajtmh.1964.13.887
Volume/Issue:
Volume 13: Issue 6
Page(s):
887–896
Restricted access
Get Permissions

Summary

Rat ectoparasite surveys made in San Juan, Puerto Rico, from 1960 to 1964 showed no increase in Xenopsylla cheopis in one section of the city, Santuree, where each year less than 5 percent of the rats were infested, whereas in another section, La Perla, there was a marked increase, the infestation rate reaching 44 percent. Laboratory colonies of a La Perla strain and of a San Francisco strain were established and tested for tolerance of DDT and dieldrin with the standard WHO technique for adults and with original techniques for larvae and pupae.

Adults of the La Perla strain were more resistant to DDT than were those of the San Francisco strain (LC50, 1.27% compared with LC50, 0.82%), and were also more resistant to dieldrin (LC50, 0.34% compared with LC50, 0.12%). As larvae and adults were found to have different toxicological characteristics, these had to be tested separately. Emergence of adults from cocoons was not suppressed by concentrations of DDT or dieldrin sufficient to kill adults and larvae. Laboratory colonies started from a single pair produced thousands of fleas in 3 months' time, indicating that a control program which fails to kill all stages of the flea may be ineffective. The flea population is made up chiefly of pupae in cocoons and larvae; adult fleas are less numerous, most being found off the rat in the breeding medium.

Author Notes

Published Online:
Nov 1964
Cover The American Journal of Tropical Medicine and Hygiene
The American Journal of Tropical Medicine and Hygiene
Print ISSN:
0002-9637
Past two years Past Year Past 30 Days
Abstract Views 593 302 25
Full Text Views 7 0 0
PDF Downloads 2 0 0
 

 

 

 
 
Affiliate Membership Banner
 
 
Research for Health Information Banner
 
 
CLOCKSS
 
 
 
Society Publishers Coalition Banner
Save