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Prevalence of Endoparasitic Infection in Children and Its Relation with Cholera Prevention Efforts in Mexico

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Prevalence of Endoparasitic Infection in Children and Its Relation with Cholera Prevention Efforts in Mexico Prevalence of endoparasitic infection in children and its relation with cholera prevention efforts in Mexico Charles T. Faulkner,1 Benito Borrego Garcia,2 Michael H. Logan,3 John C. New,1 and Sharon Patton1 ABSTRACT Objective. To investigate whether increased knowledge and use of public health measures promoted for cholera prevention is reflected in lower prevalence of parasitic infection in house- holds in a community in the state of Tamaulipas, Mexico, that is close to the border with the United States of America. Methods. Between 1994 and 1997, fecal samples from 438 children were collected through convenience sampling and then examined for helminth eggs/larvae and protozoan cysts as bio- logic indicators of household compliance with recommended cholera prevention measures. The suggested measures were to wash hands before meals and after defecation, to drink purified water, to wash fruits and vegetables, and to eat well-cooked food. In addition, information on the knowl- edge of and the use of cholera preventive measures was collected by interviews with adult infor- mants in 252 households (186 of those households also provided a fecal sample for analysis). Results. Parasitic infections occurred in 131 of the 438 children (30%), who resided in 79 of the 186 households (42%) that provided fecal samples. Giardia lamblia accounted for 12.5% of all infections. Infections with Hymenolepis nana, Ascaris lumbricoides, Trichuris tri- chiura, Enterobius vermicularis, Ancylostoma/Necator, Strongyloides stercoralis, En- tamoeba coli, Entamoeba hartmanni, Entamoeba histolytica, Endolimax nana, and Io- damoeba bütschlii were also noted. Infected children were older and more often had an infected sibling. Households with three or more children were also more likely to have an infected child. The primary caregivers in the households where at least one child had a parasitic infection were distinguished by their inability to list at least three cholera prevention measures from memory. Conclusions. The 42% household prevalence of parasitic infection was relatively high and indicates that some residents of this community may not have fully embraced the public health education efforts promoted for prevention of cholera. The occurrence of nonpathogenic protozoan parasites such as Endolimax nana, Entamoeba coli, Entamoeba hartmanni, and I. bütschlii are important bioindicators for the persistence of unhygienic behaviors that increase the risk of cholera and other infectious diseases dependent on fecal-oral transmission. Informa- tion obtained by similar studies can be useful for monitoring compliance with community health and hygiene programs and may indicate the need to intensify educational efforts for the preven- tion of diarrhea associated with enteric pathogens that cannot be controlled by drugs alone. Key words Cholera; parasitic diseases; health education; knowledge, attitudes, practice; Mexico. 1 University of Tennessee, Department of Compara- University of Tennessee, 2407 River Drive, Knox- 2 Médico veterinario zootecnista, Valle Hermoso, tive Medicine, Knoxville, Tennessee, United States ville, Tennessee 37796-4543, United States of Amer- Tamaulipas, Mexico. of America. Send correspondence to: Charles T. ica; telephone: (865) 974-5718; fax: (865) 974-5640; 3 University of Tennessee, Department of Anthropol- Faulkner, Department of Comparative Medicine, e-mail: [email protected] ogy, Knoxville, Tennessee, United States of America. Rev Panam Salud Publica/Pan Am J Public Health 14(1), 2003 31 The epidemic spread of Vibrio cho- community would be reflected in lower rounding communities and establish lerae, biotype El Tor, serotype Inaba, occurrence of infection with intestinal homes in neighborhoods developing into Latin America in 1991 prompted a protozoan and helminth parasites be- on the outskirts of Valle Hermoso. Con- vigorous response from public health cause their transmission is facilitated structed of concrete block or wood agencies at the international, national, by the same unhygienic behaviors that frame with plywood or flat-board sid- state, and local community levels (1–4). increase risk for cholera. ing, the houses in these neighborhoods Education materials disseminated These unhygienic behaviors include have between one and three rooms. to the public described the nature of inadequate hand-washing, drinking Electrical utilities and running water in- the disease and provided recommen- contaminated water, eating improp- side the house are available in approxi- dations for prevention of infection by erly washed fruits and vegetables, and mately 90% of the households (7). Out- cholera and similar pathogens. Many promiscuous defecation habits. The oc- side latrines are the primary method for residents of these countries became currence of nonpathogenic protozoan disposal of fecal waste, and only 19% of acutely aware of the fecal-oral route of parasites such as Endolimax nana, Io- the households have indoor toilets (7). cholera transmission and the impor- damoeba bütschlii, Entamoeba coli, and The decision to conduct this inves- tance of personal and household hy- Entamoeba hartmanni in populations tigation in Valle Hermoso was moti- giene measures in maintaining health. targeted by interventions to prevent vated primarily by our preexisting Increased promotion of personal hy- cholera are important bioindicators for relationship with local government giene measures such as frequent hand- unhygienic behavior because these officials and health department per- washing, consumption of bottled or parasites do not produce clinical dis- sonnel. The relatively small size of the chemically treated water, and thor- ease and are not treated by physicians. community and its convenient dis- oughly washing fruits and vegetables Use of these parasites as bioindicators tance from the border with the United prior to consumption helped mitigate of unhygienic behavior provided us States were secondary considerations the adverse impact of the cholera epi- with a method for objectively evaluat- that made this an attractive place for demic throughout Latin America, in- ing the quality of information on the the investigation. cluding Mexico (3–4). These efforts may knowledge and practice of cholera pre- have also had an additional effect on ventive measures obtained from inter- the community—wide prevalence of views with the primary caregivers in Household enlistment infection with endoparasitic helminths participating households. This investi- and data collection and protozoa dependent on the fecal- gation offered a unique opportunity to oral transmission route. De la Sotta examine an important dimension of All of the households in the study and colleagues (5) suggested that the human behavior by comparing what were located in neighborhoods that Chilean cholera control program was informants say they do with what they had been the focus of recent public responsible for a statistically signifi- actually do. The information obtained health education initiatives to reduce cant decrease in intestinal parasitoses through this research can be used by childhood morbidity from cholera and diagnosed at hospitals in the city of public health workers to monitor com- diarrheal disease produced by para- Santiago during the 3-year period that pliance with community health and sitic and other infectious enteric agents. followed a national campaign. How- hygiene programs, and it may indicate The ongoing educational effort was ever, this association may have been the need to intensify educational ef- initiated in 1993, that is, the year be- coincidental because Santiago resi- forts for prevention of diarrhea associ- fore the start of this investigation, and dents were not interviewed to deter- ated with enteric pathogens such as it was carried out by local committees mine if they knew or used any of the cholera, Salmonella, Cryptosporidium sp., of volunteer health promoters trained anti-cholera recommendations. and Giardia lamblia that cannot be con- to work under the supervision of We undertook our research to inves- trolled by drugs alone. nurses from a Valle Hermoso health tigate the impact that a locally admin- center operated by the Government’s istered program to prevent cholera had Secretariat of Health (Secretaría de Sa- on the prevalence of endoparasitic in- METHODS lud). Having the health promoters fection in households of a small com- structure already in place maximized munity in the state of Tamaulipas, in This study was carried out between our access to households and helped northeastern Mexico. Like de la Sotta 1994 and 1997 in Valle Hermoso, Ta- assure rapport with subjects. and colleagues (5), we were intrigued maulipas, Mexico, a community of Some of the participants enlisted in by the possibility that increased com- 39 004 persons located 45 km south the study during open meetings with munity awareness and utilization of of the border with the United States of health educators and two of the au- cholera prevention measures could re- America (6–7). Employment and in- thors (CTF and BBG). At these meet- duce the prevalence of intestinal para- vestment opportunities arising from ings the project objectives were de- sitic infections. We hypothesized that recent industrial growth and increased scribed by the two authors (CTF and household compliance with the edu- trade with the United States have BBG), and the participants received in- cational initiative undertaken in this prompted people to relocate from sur- structions for collecting fecal
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