[Selective vs. mass treatment with antihelminthic drugs: experience in two hyperendemic communities].
OBJECTIVE
To compare the prevalence and intensity of soil-transmitted nematode infection among children from two hyperendemic communities who were treated with antihelminthic drugs under two different regimens: selective or individual treatment was administered to members of one of the communities, and repeated mass treatment was given to the control community.


METHODS
The study population was comprised of 909 children of both sexes between the ages of 2 and 13 from two peri-urban communities: Las Lomas and El Abastos, both in Santa Fe, Argentina. A prospective, longitudinal, quasi-experimental study was carried out in these communities. During the 22-month study period, 5 parasitologic controls were performed and results were qualitatively and quantitatively examined. Treatment with antihelminthic drugs was given at controls 0, 2, 3, and 4. At Las Lomas, selective treatment was administered to those in sample A (n = 55) who were positive for parasites; in El Abasto, mass treatment was given to all children, including those in sample B (n = 50). Both samples received follow-up.


RESULTS
The prevalence and intensity of A. lumbricoides infections were found to be significant in El Abasto. No differences were detected in the case of T. trichiura. When prevalence and parasitic burden of A. lumbricoides were compared among controls within a single community (at the beginning and end of the study), no significant differences were observed in sample A, but a significant difference was seen in sample B. Insofar as T. trichiura is concerned, there were significant differences among controls in both samples.


CONCLUSIONS
Only repeated and massive treatment significantly lowered the prevalence and intensity of A. lumbricoides infections during the study period.
Beltramino
Daniel
D
Servicio de Pediatría, Hospital J. B. Iturraspe, Santa Fe, Argentina. dbeltramino@gigared.com
Lurá
María Cristina
MC
Carrera
Elena
E
D000293:Adolescent; D000818:Animals; D000969:Antinematodal Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001118:Argentina / Q000453:epidemiology; D001196:Ascariasis / Q000188:drug therapy* / Q000453:epidemiology*; D017164:Ascaris lumbricoides; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008463:Mebendazole / Q000008:administration & dosage / Q000627:therapeutic use*; D011446:Prospective Studies; D017171:Strongyloides stercoralis; D013322:Strongyloidiasis / Q000188:drug therapy* / Q000453:epidemiology*; D013827:Thiabendazole / Q000008:administration & dosage / Q000627:therapeutic use*; D013997:Time Factors; D014257:Trichuriasis / Q000188:drug therapy* / Q000453:epidemiology*
D000969:Antinematodal Agents; D008463:Mebendazole; D013827:Thiabendazole