Rate of reinfection with S. mansoni following treatment in two newly reclaimed areas of Egypt.

This paper reports an on-going study in two newly reclaimed areas in Ismailia Governorate, El-Manayef, 10 km south-west of the city of Ismailia (area 1) and the other in Siani Peninsula, just east of the Bitter Lakes (area 2). In he baseline survey, the prevalence of infection of 49.9% and 40.1% and high intensity infection of 21.8% and 15.7% were found for S. mansoni in areas 1 and 2 respectively. Geometric mean egg counts for those found positive were 101.2 and 75.9. In a subsequent survey, a year after treatment of positives, the overall prevalence was 30.2% and 30.5% and the prevalence of high intensity infection was 8.6% and 10.5% in the two areas. The prevalence among those found positive and then treated during the first round (reinfection rate) was 31.7% and 19.2%. Geometric mean egg counts had declined from 141.3 to 63.1 and from 133.6 to 59 among those who were reinfected. The occurrence of reinfection was strongly associated with younger age in both areas. Rates of reinfection showed a strong but not significant association with male sex in area 2 (p = 0.087), but no association in area 1. These high rates of reinfection demonstrate the importance of promotion of hygiene behaviors as well as ensuring access to chemotherapy.

Factors affecting knowledge of the symptoms of schistosomiasis in two rural areas near Ismailia, Egypt.

The primary method of control of schistosomiasis in Egypt is through passive chemotherapy, in which people who suspect they have the disease are encouraged to go to their local health unit to be tested and treated. If people are unable to recognize the symptoms of schistosomiasis, this strategy may fail. This paper presents data on local knowledge of the symptoms of schistosomiasis from two areas recently reclaimed from the desert near Ismailia. Using data from free-listing and triadic comparisons, it is shown that schistosomiasis is primarily seen as a urinary disease. Factor analysis performed on a series of 12 questions on the symptoms of schistosomiasis included in a survey demonstrated that responses group into three patterns, the first stressing constitutional symptoms such as weakness, the second stressing abdominal symptoms and the third blood in the urine, burning on urination and blood in the stool. The paper discusses the implications of these findings for efforts to promote regular treatment with praziquantel of people living in or near the Nile Delta who are at risk for intestinal schistosomiasis.

The prevalence of hepatitis B and C infections among immigrants to a newly reclaimed area endemic for Schistosoma mansoni in Sinai, Egypt.

Serology for hepatitis B and C markers was performed on a community-based random sample of 506 residents of an area recently reclaimed from the desert and endemic for Schistosoma mansoni. The mean age of the study subjects was (20 +/- 14), and 52% were males. The overall seroprevalence of hepatitis B (Anti-HBc and/or HBsAg) was 19.6%, hepatitis C (Anti-HCV) was 10.3%, while 5% were positive for both hepatitis B and C. A strong association was present with increasing age for both hepatitis B and C markers. However, there was no association with either sex, S. mansoni infection or schistosomal periportal fibrosis. Also HBV seropositivity was not associated with increased risk of HCV seropositivity. Anti-HCV seropositivity was significantly associated with previous parenteral treatment for schistosomiasis (OR = 7.9), and with history of previous surgery (OR = 3). Hepatitis B and C are major public health problems in this population. It is recommended to consolidate the Egyptian programme of infant hepatitis B vaccination, and to extend it to older children and high risk adult groups. There is also an urgent need to study more closely the epidemiology, natural history, risk factors and modes of transmission of hepatitis C.

PIP: In Egypt, infection with hepatitis B (HBV) and C (HCV), together with schistosomiasis are major causes of chronic liver disease. Findings are presented from a study conducted in January 1994 to determine the prevalence of HBV and HCV infections in a Schistosoma mansoni-endemic area east of the Bitter Lakes recently reclaimed from the desert for agriculture. Serology for hepatitis B and C markers was performed on a community-based random sample of 506 area residents of mean age 20 years, and 52% male. The seroprevalences of hepatitis infection were 19.6% for HBV, 10.3% for HCV, and 5% both HBV and HCV. The prevalence of HBV and HCV markers generally increased with age. No association, however, was found with either sex, S. mansoni infection, or schistosomal periportal fibrosis. HBV seropositivity was not associated with increased risk of HCV seropositivity. Anti-HCV seropositivity was significantly associated with previous parenteral treatment for schistosomiasis and history of previous surgery. HBV and HCV infection is a major problem in this population. The Egyptian program of infant hepatitis B vaccination should be consolidated and extended to older children and high-risk adult groups. There is also an urgent need to study more closely the epidemiology, natural history, risk factors, and modes of hepatitis C transmission.

Prevalence and epidemiology of Schistosoma mansoni and S. haematobium infection in two areas of Egypt recently reclaimed from the desert.

Projects are being carried out in many regions of Egypt to reclaim land from the desert for agriculture. This paper presents findings from a baseline epidemiologic study conducted in 1992 in two newly reclaimed areas near Ismailia, Egypt. In the first area, just east of the Suez Canal, 40.0% of the residents tested positive for Schistosoma mansoni and 1.7% tested positive for S. haematobium, while in the second area, 15 km southwest of Ismailia, 49.3% tested positive for S. mansoni and 3.3% tested positive for S. haematobium. The intensities of S. mansoni infection were moderately high, with a geometric mean egg count of 76 eggs/gram of feces among positive individuals in the first area, and 100 eggs/gram of feces in the second area. When compared with a previous study conducted in 1985, the prevalence of S. mansoni infection in the first area has increased from 21.7% to 42.1% among settlers in the last seven years, while that of S. haematobium has decreased from 7.8% to 1.7%. These trends may result from changes in irrigation practices or other alterations in the local environment. There is a risk of schistosomiasis becoming a major public health problem in reclaimed areas if adequate control measures are not taken.

Social and economic conditions in two newly reclaimed areas in Egypt: implications for schistosomiasis control strategies.

Reclamation of land from the desert is currently taking place in all parts of Egypt. A side-effect of many of these projects has been the introduction of schistosome parasites and their snail intermediate hosts, sometimes among Bedouin population with no previous exposure to the disease. The purpose of the present study was to describe social, environmental and economic conditions which can affect the transmission and control of schistosomiasis in reclaimed areas, and to investigate how residents of these areas view local conditions. Two areas were found to have high rates of internal and external migration, many different social groups with widely divergent priorities and minimal contact with each other, and inadequate infrastructure in terms of roads, transport, water and sanitation and health services. As a result of these conditions, control strategies which are effective for the population living in the Nile Valley will have to be modified considerably if schistosomiasis is to be brought under control in reclaimed areas.