The prevalence, intensities and risk factors associated with geohelminth infection in tea-growing communities of Assam, India


Rebecca Justine Traub, R. C. Andrew Thompson (corresponding author), Ian D. Robertson and Peter Irwin, World Health Organisation Collaborating Centre for the Molecular Epidemiology of Parasitic Infections, Division of Veterinary and Biomedical Sciences, Murdoch University, South Street, Murdoch, Perth, Western Australia 6150. Tel.: +61-8-93602466; Fax: +61-8-93104144; E-mail:,,,
Norbert Mencke, Bayer AG, BHC-Business Group Animal Health, 51368 Leverkusen, Germany. Tel.: +49-2173-384285;Fax: +49-2173-384956; E-mail:


Objective  To determine the prevalence, intensity and associated risk factors for infection with Ascaris, hookworms and Trichuris in three tea-growing communities in Assam, India.

Methods  Single faecal samples were collected from 328 individuals and subjected to centrifugal floatation and the Kato Katz quantitation technique and prevalence and intensities of infection with each parasite calculated. Associations between parasite prevalence, intensity and host and environmental factors were then made using both univariate and multivariate analysis.

Results  The overall prevalence of Ascaris was 38% [95% confidence interval (CI): 33, 43], and the individual prevalence of hookworm and Trichuris was 43% (95% CI: 38, 49). The strongest predictors for the intensity of one or more geohelminths using multiple regression (P ≤ 0.10) were socioeconomic status, age, household crowding, level of education, religion, use of footwear when outdoors, defecation practices, pig ownership and water source.

Conclusion  A universal blanket treatment with broad-spectrum anthelmintics together with promotion of scholastic and health education and improvements in sanitation is recommended for helminth control in the communities under study.