Southeast Asian J Trop Med Public Health

A cross sectional survey of Enterobius vermicularis was carried out in 808 children in the Bangkok metropolis and nearby provinces. This was accomplished in a mobile health clinic from Huachiew Chalermprakiet University provided for communities in the areas during April 1999 to May 2000. Children 5-10 years of age were investigated for infestation of Enterobius vermicularis. Diagnosis was done by means of the transparent tape swab technique to recover eggs in the perianal region for examination under a light microscope. The average infection rate in children was 21.91% . The highest infection rate (38.59 %) was found in Ang Thong Province, while the lowest one (11.66 %) was found in Chonburi Province. The rate of infection seemed to relate to household environmental factors. The infection rate was significantly higher (p<0.05) in agricultural areas and areas farthest from urban Bangkok. Industrial and urban areas had the lower rates of infection. There was no significant difference (p>0.05) in the incidence of infection between males and females. Various studies have been done to determine the prevalence of helminth infection in Thailand. Different methods of diagnosis were utilized, including the preparation of feces for examination by Kato’s thick smear technique. The rate of enterobiasis thus determined, varied according to the geographical region. The rate of infection in Northern Thailand was 0.58%, 0.28% in the southern region, 0.27% in the central region, and 0.20% in the northeast. The highest prevalence of infection was found in children five to nine years of age (Preuksaraj et al, 1982; Jongsuksantigul et al, 1992). There was no significant relationship between the sex of the subjects and the rate of infection (Vajarasthira and Harinasuta, 1960). Population density and personal hygiene were significant factors in the distribution and prevalence of infection, however. This could explain consistently higher prevalences found in overcrowded areas such as slums (Tepmongkol et al, 1980; Teopipitporn et al, 1981), as well as in orphanages and schools (Mameechai et al, 1992; Wahah and Ratanaponglakh, 1992) where large numbers of young children are in close proximity. At present, we lack extensive data concerning the rates of infection in various areas and among different populations. It would be of interest to examine difference in urban residential, industrial, and rural agricultural areas. We chose to investigate the prevalence of enterobiasis in the Bangkok metropolitan area and the surrounding regions. We felt the data from an investigation of this area would assist us in developing INTRODUCTION The pinworm, Enterobius vermicularis, is one of the most common parasites infecting Homo sapiens worldwide. The archeological history shows this association to go back to the earliest origins of mankind. It is a species of Oxyurdia belonging to the phylum of nematodes, or roundworms. Pinworm infestation commonly causes irritation in its victims, however severe infestations can result in pathogenesis in various organs including the lung (Bever et al, 1973), liver (Daly and Baker, 1984; Slais, 1963), appendix (Cerva et al, 1991), and female genitals and reproductive organs (Mayayo et al, 1986; Beckman and Holland, 1981; Kogan et al, 1981; McMohan et al, 1984). Pinworms are prevalent in both the tropics and temperate regions of the world. Enterobius vermicularis is particularly widespread among school-aged children. Research done in the United States of America reported an average prevalence rate in children of around 30% (Smith and Gutierrez, 1984). Studies done in urban slum areas in Bangkok, Thailand showed a rate of infection varying from 53% to around 65% (Tepmongkol et al, 1978; Teopipiporn et al, 1981). Studies of preschool aged children in Khon Kaen Province in the northeastern region of Thailand indicated a prevalence of around 50.9% (Kaewkes et al, 1983). Research in Nakhon Pathom Province, an urban area adjacent to Bangkok, exhibited a prevalence rate of 38.2%. (Wahah and Ratanaponglakh, 1992).