Table of Contents Author Guidelines Submit a Manuscript
Interdisciplinary Perspectives on Infectious Diseases
Volume 2012, Article ID 409757, 5 pages
Research Article

Adaptation of Ritchie's Method for Parasites Diagnosing with Minimization of Chemical Products

1Central Laboratory of Clinical Pathology, University Hospital, University of São Paulo at Ribeirão Preto Medical School, 14040-902 Ribeirão Preto, SP, Brazil
2Laboratory of Ecotoxicology and Environmental Parasitology, University of São Paulo at Ribeirão Preto College of Nursing, Avenida Bandeirantes 3900, Campus Universitário, 14040-902 Ribeirão Preto, SP, Brazil
3Microtechnics/Metal Sector, University of São Paulo at Ribeirão Preto Medical School Hospital das Clínicas, 14040-902 Ribeirão Preto, SP, Brazil

Received 31 May 2012; Accepted 8 July 2012

Academic Editor: Oladele O. Kale

Copyright © 2012 Régis Silva Anécimo et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Latin America, Africa, and Asia present wide dissemination and high prevalence rates of waterborne parasitic diseases, which is a strong indicative of the fragility of public sanitation systems. In this context, parasitological analyses represent extremely relevant instruments. Several parasite diagnosis methods exist, among which Ritchie’s method (1948) stands out. This method uses formaldehyde and ether, two reagents of toxicological importance that can cause damages to environmental and occupational health. The present study aimed to compare Ritchie’s method modified by Régis Anécimo, without use of solvents, with the traditional Ritchie’s method, routinely used for helminth and protozoa diagnosing in Brazil. Some changes were introduced in the modified method, such as controlled increase of water temperature used after stool dilution and substitution of formaldehyde and ether by a neutral detergent before material centrifugation for observation of parasites. In examined samples by both methods, multiple infections were commonly observed; the modified method presented a similar sensitivity to identify the parasites. The development of analytic diagnosis methods that minimize the use of chemical products like ether and formaldehyde represents an important tool to prevent occupational diseases among exposed professionals, as well as to preserve environmental quality through the use of clean techniques.