[Hepatitis C virus infection among pregnant women and their children in Norway]. / Hepatitt C-virusinfeksjon hos gravide og barn i Norge.

Estimates indicate the births of 6 to 78 children vertically infected with hepatitis C virus infection each year in Norway. There is insufficient knowledge of the magnitude of this health problem and the National Institute of Public Health commissioned the authors to approach issues relating to vertical transmission of hepatitis C virus (HCV) infection in Norway. The risk of vertical transmission of HCV appears to be associated with the titre of the maternal viral load. Vertical transmission from nonviraemic mothers has not been demonstrated. No postexposure prophylaxis exists. There is a lack of association between vertical HCV transmission and delivery mode and no association with breast feeding. Universal screening for HCV infection among pregnant women is not recommended. Children born to women known to be HCV-positive should be followed up with antibody and polymerase chain reaction investigations in order to clarify their HCV status. More studies of HCV infection among pregnant women and their children in Norway are needed.

Delayed reinfection of Schistosoma mansoni in the Blue Nile Valley of western Ethiopia 10 years after mass chemotherapy.

In the Blue Nile Valley of western Ethiopia a successful control programme against Schistosomiasis mansoni starting from 1985 was in 1989 interrupted by local guerrilla warfare. The control was based on human mass chemotherapy campaigns during the rainy season of 1985 and 1986 and a limited annual, focal molluscicidal activity where re-infection was demonstrated. In 1995 the area was revisited and selected schools in previously hyperinfected villages were examined for reinfection. The results were compared to re-calculated figures for the 5-19 year age group from previous pre-, per- and post-control surveys in the same localities. In 1995 prevalence rates in the 5-19 year age group had risen to 68% (Salba-Korka) and 63% (Sirba), which are very close to the 1985-1986 pre-control prevalences. Infection intensities, however, had not risen to the same degree. In Salba-Korka the 1986 pre-control geometric mean S. mansoni eggs per gram of faeces in the 5-19 year age group was 73, after mass treatment until 1989 it was close to 0, whereas in 1995 it was still only 27. In Sirba the result was similar. This might indicate a slower transmission rate after the control period than previously. The reported seasonality of transmission and the local use of the molluscicidal bark of the 'Bitza' tree might possibly have had some delaying effect.

Control of Schistosoma mansoni in the Blue Nile Valley of western Ethiopia by mass chemotherapy and focal snail control: a primary health care experience.

A simplified combination of human mass treatment with oxamniquine and focal snail control has been applied in a local Schistosoma mansoni control programme in a primary health care setting in the Dalati and Agallu Metti areas of the Ethiopian Blue Nile Valley. Teams of local health personnel and farmers did the daily work under intermittent supervision. Monthly snail surveys near the major villages disclosed a seasonal pattern with many infected snails during the dry season in upper stagnant sections of tributary rivers (1000-1200 m altitude) with favourable temperatures, and few snails in the rainy season. The highest prevalences and intensities of human infection were found in the 15-19 year age group living in the lower altitudes around 700 m. 5067 individuals (50-80% of the local population) were treated with 20-40 mg oxamniquine per kg body weight during the rainy seasons of 1985 (Dalati) and 1986 (Agallu Metti). In the Dalati area cross sectional surveys in 1985 and 1986, before and after the mass treatment, showed a reduction in prevalence from 42.4% to 11.4%, while in the Agallu Metti area a stratified random sample showed a prevalence reduction from 65.4% in 1986 to 7.8% in 1987 and a reduction in the prevalence of moderate to heavy infection (greater than 100 eggs per gram of stool) from 36.9% to 1.4%. Beginning in 1986 niclosamide was applied focally wherever infected snails were found and the monthly snail surveillance continued until 1989. As a result of this combined approach overall snail infection rates were reduced from 11.2% (Dalati) and 32% (Agallu Metti) to zero and 2% respectively. In 1989 the human prevalence was still only 8.6% in Agallu Metti. This programme has shown that it is feasible to control S. mansoni in these very remote localities through the primary health care system.