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The purpose of this study was to identify risk factors for hepatitis C virus (HCV) infection in a rural village in the Nile Delta with a high prevalence of antibodies to HCV (anti-HCV). One half of the village households were systematically selected, tested for anti-HCV, and interviewed: 973 of 3,999 (24.3%) subjects were anti-HCV-positive (reflecting prior HCV infection but not necessarily current liver disease), with nearly equal prevalence among males and females. Anti-HCV prevalence increased sharply with age among both males and females, from 9.3% in those 20 years of age and younger to >50% in those older than 35, suggesting a cohort effect with reduced transmission in recent years. Multivariate regression was used to estimate independent effects of risk factors on seropositivity. Among those over 20 years of age, the following risk factors were significantly associated with seropositivity: age (P < . Previous studies of hepatitis C viral (HCV) infection in Egypt have shown a high prevalence of antibody to HCV (anti-HCV) among blood donors 1-4 and residents of rural areas endemic for schistosomiasis. 5 Anti-HCV was found in 12.1% of primary schoolchildren, 18.1% of residents of rural villages, and 22.1% of army recruits, 6 as well as in 31% of Egyptians applying to work abroad. 7,8 It is widely believed that parenteral exposure to the virus is the most important route for acquiring infection in Egypt. 7,9 We have recently reported data that suggest the very high prevalence of HCV infection in the adult population of rural areas of Egypt, particularly in men living in villages where schistosomiasis is endemic, is at least partially the result of extensive mass-control campaigns using parenteral tartar emetic conducted from the 1950s up until 1982. 10 Although the prevalence of infection among those too young to be exposed to these mass antischistosomiasis injection campaigns is lower than among the older population, infection in this younger cohort indicates that other modes of transmission have perpetuated the infection in the community. Uncertainty remains regarding the relative importance of various types of parenteral exposures and widely practiced community activities, e.g., circumcisions, goza smoking in a group, or being shaved at a community barber.To resolve this uncertainty, we conducted a large serologic survey in a rural Egyptian community. The purpose of this article is to report the observed associations of HCV infection with both the acknowledged parenteral exposures (e.g., blood transfusions, injections, invasive hospital procedures, dental treatment) and widely practiced community activities that are usually not considered to be determinants of HCV transmission. PATIENTS AND METHODSStudy Population. In 1997, one half of the households of a village in the Nile Delta, Aghour El Soughra, were systematically selected and interviewed with a structured questionnaire to identify potential exposures that might be related to HCV acquisition. Adults and children older than 10 years of age were interv...

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Since the publication of the International Programme on Chemical Safety (IPCS) Harmonized Scheme for Mutagenicity Testing, there have been a number of publications addressing test strategies for mutagenicity. Safety assessments of substances with regard to genotoxicity are generally based on a combination of tests to assess effects on three major end points of genetic damage associated with human disease: gene mutation, clastogenicity and aneuploidy. It is now clear from the results of international collaborative studies and the large databases that are currently available for the assays evaluated that no single assay can detect all genotoxic substances. The World Health Organization therefore decided to update the IPCS Harmonized Scheme for Mutagenicity Testing as part of the IPCS project on the Harmonization of Approaches to the Assessment of Risk from Exposure to Chemicals. The approach presented in this paper focuses on the identification of mutagens and genotoxic carcinogens. Selection of appropriate in vitro and in vivo tests as well as a strategy for germ cell testing are described.

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