No abstract

Abstract. This investigation's objective was to identify risk factors for hepatitis C virus (HCV) in a village in Upper Egypt with a moderately high prevalence (8.7%) of antibodies to HCV (anti-HCV). A representative sample of 6,012 (63%) of the 9,581 village inhabitants was included in the study. A questionnaire solicited information regarding risk factors for infection, and blood samples were tested for anti-HCV. Parenteral risks identified in age-adjusted analysis included blood transfusions, dental procedures, hospital admission, surgery, complicated deliveries, history of injection therapy for schistosomiasis, and history of frequent injections. Circumcision was pervasive and was not associated per se with ant-HCV; however, circumcision by an informal, rather than formal, health care provider was associated with anti-HCV among young men and boys. The results did not reveal any unique community-acquired exposures that caused HCV infections: inhabitants who had tattoos, who smoked goza, who were shaved by a community barber, or who had their ears pierced were not at greater risk for anti-HCV than those who did not. Risks identified in multivariate analysis for both those older and younger than 30 years included prior parenteral therapy for schistosomiasis and blood transfusion; for those 30 or younger, circumcision by an informal rather than formal health care provider, and frequent injections; and for those older than 30, never attending college, invasive medical procedures, and complicated deliveries. Selecting for those with blood transfusion, prior parenteral therapy for schistosomiasis, and invasive medical procedures would identify less than half of those infected. Inclusion of frequent injections would identify 80% of those infected with HCV, but as a result of the pervasive use of injections, it would not discriminate from those uninfected. Nonetheless, general reduction of these exposures and assuring sterile practices are logical goals for intervention.

Abstract. The prevalence of antibody to hepatitis C virus (anti-HCV) was determined in a cross-sectional survey in a village in Upper Egypt. Exposure and demographic characteristics were obtained through a questionnaire. Antibody to hepatitis C virus was assessed using a second generation enzyme immunoassay, and the presence of HCV RNA was tested using a reverse transcriptaseϪpolymerase chain reaction. Collection of blood samples was targeted at those Ն 5 years old, and obtained from 62.8%. This report describes the community, the HCV infection characteristics of the subjects, and evaluates some factors associated with presence of anti-HCV. Of the 6,031 participants, 522 (8.7%) were anti-HCV positive. Prevalence was higher among males than females (11.3% versus 6.5%; P Ͻ 0.001). It was greater among those Ͼ 30 years of age than among those Յ 30 years of age (20.0% versus 3.6%; P Ͻ 0.001). Those who were less educated, farmed, provided health care, and were currently married had a significantly higher anti-HCV prevalence than those who were not; however, these associations were not significant after adjusting for age. Although active infections with Schistosoma haematobium were not associated with anti-HCV, a history of past infection was (age-adjusted risk ratio [RR] ϭ 2.1, 95% confidence interval [CI] ϭ 1.8, 2.4); 134 persons who had a history of receiving parenteral anti-schistosomal therapy had a higher age-adjusted RR (3.0; 95% CI ϭ 2.5, 3.7) for anti-HCV than those who did not. Hepatitis C virus RNA was detected in 62.8% of the anti-HCV positive subjects, without significant variation by age, gender, education, or marital status. The prevalence of anti-HCV in Upper Egypt is high, albeit lower than in Lower Egypt, with continuing but limited transmission indicated by the lower prevalence in residents Յ 30 years old.

Abstract. A population-based serosurvey in two rural Egyptian communities was used to assess age-specific prevalence of antibody to hepatitis E virus (anti-HEV). One community is in the Nile Delta (11,182 inhabitants; 3,997 participants) and the other in Upper Egypt (10,970 inhabitants; 6,029 participants). Samples were tested for anti-HEV with a commercial enzyme-linked immunoassay (ELISA) based on antigens derived from open reading frame (ORF)2 and ORF3. Although there was a clear difference in sensitivity among the lots of the commercial test used, it was still possible to determine the seroprevalence. The seroprevalence of anti-HEV exceeded 60% in the first decade of life, peaked at 76% in the second decade and remained above 60% until the eighth decade. Prevalence of this magnitude is among the highest reported in the world, with an age-specific pattern more similar to hyperendemic hepatitis A virus transmission than generally described. Lot-to-lot variation in the sensitivity of the commercial ELISA kit highlights a problem when comparing seroepidemiologic studies of different populations.

Acquired immunity to human schistosomiasis correlates with increased serum levels of schistosome antigen-specific IgE. Since interleukin (IL)-4 stimulates IgE production, the hypothesis that Th2-associated cell-mediated immunity participates in protection to reinfection was studied in a cohort of adolescent boys 12-18 months after chemotherapeutic cure in Upper Egypt. Initial Schistosoma haematobium prevalence was 51% and posttreatment incidence was 44%. Water contact was similar between putatively resistant and susceptible patients. Resistant persons had a 3.5- to 14-fold greater frequency of schistosome adult worm antigen (SWAP)-specific lymphocytes secreting IL-5 or IL-4 (by ELISPOT) and IL-5 or IL-4 production in peripheral blood lymphocyte culture supernatants (P < .05 to < .001, n = 48) versus susceptible subjects (n = 38). In contrast, SWAP-induced interferon-gamma and IL-10 production and lymphocyte proliferation were similar between the 2 groups. Schistosome egg antigen and streptolysin O each stimulated similar cytokine production in susceptible and resistant persons. Thus, enhanced SWAP-driven IL-4 and IL-5 production correlates with immunity to reinfection in adolescents exposed to urinary schistosomiasis.

Although the seroprevalence of hepatitis E virus (HEV) is approximately 80% in adult Egyptians living in rural areas, symptomatic HEV-caused acute viral hepatitis (AVH) is sporadic and relatively uncommon. To investigate the dichotomy between HEV infection and clinical AVH, HEV-specific immune responses in patients with symptomatic and asymptomatic HEV infection during a waterborne outbreak in Egypt were examined. Of 235 acute hepatitis patients in Assiut hospitals screened for HEV infection, 42 (17.9%) were acute hepatitis patients confirmed as HEV-caused AVH; 37 (88%) of the 42 patients were residents of rural areas, and 14 (33%) were from one village (Kom El-Mansoura). Another 200 contacts of AVH cases in this village were screened for HEV and 14 (7.0%), all of whom were family members of AVH cases, were asymptomatic HEV IgM-positive. HEV infections in this village peaked during the summer. Asymptomatic HEV seroconverters had significantly higher levels of epitope-specific neutralising (p=0.006) and high avidity (p=0.04) anti-HEV antibodies than the corresponding AVH cases. In conclusion, naturally acquired humoral immune responses appear to protect HEV-exposed subjects from AVH during an HEV outbreak in Egypt.

In the Assiut, Egypt Epidemiology 1, 2, 3 investigation, a sample of 14,204 persons in 10 villages, 31 ezbas (satellite communities), and 2,286 households was drawn from a rural population of 1,598,607. Parasitologic examination of urine and stool were made for Schistosoma haematobium and S. mansoni, and physical and ultrasound examinations were made on a 20% subsample. The overall estimated prevalence of S. haematobium was 5.2 Ϯ 0.5 (Ϯ SE). This varied considerably by village and ezba, ranging from 1.5% to 20.9%, with ezbas having a slightly higher overall prevalence than villages. The overall estimated geometric mean egg count was 6.6 Ϯ 0.5 eggs per 10 ml of urine and was consistently low throughout the communities. Infection with S. haematobium was associated with age (peak prevalence of 10.6 Ϯ 1.5% in 15-19-year-old age group) males, children playing in the canals, a history of blood in the urine, and reagent strip positivity for hematuria and proteinuria. The prevalence of either hepatomegaly or splenomegaly detected by physical examination was low (4.0% and 1.5%, respectively). The prevalence of hepatomegaly determined by ultrasonography was substantially higher, 24.1%. The prevalence of periportal fibrosis (PPF) was 12.0%, but grade II or III PPF was present in less than 1%. Ultrasonography-determined hepatomegaly, in both the midclavicular line and the midsternal line, increased by age to more than 30%. Periportal fibrosis was more common in the age groups in which infection rates were the highest. At the village and ezba level of analysis, the prevalence of hepatomegaly, splenomegaly, and PPF tended to be higher in communities having the highest prevalence of infection with S. haematobium.

No abstract