[An outbreak of Yersinia enterocolitica O:9-infection].

Background: Yersiniosis is a zoonosis that is transmitted from pigs to humans. In January 2006 more cases of Yersinia enterocolitica enterocolitis than expected were reported in Norway. The fact that the isolates belonged to the O:9 serogroup, which is rare in Norway, and the geographical and temporal clustering of the cases, pointed to an outbreak.

Respiratory syncytial virus infections in congenital heart defects--hospitalizations and costs.

Aims: To register hospitalizations for respiratory syncytial virus (RSV) infections and estimate costs of prophylaxis with humanized monoclonal antibodies (palivizumab) against RSV, compared to hospital care, in cases with congenital heart defects (CHDs).

Methods: Population based study with prospective registration of CHDs. Costs for hospital treatment of RSV-infections in CHD-patients calculated by means of the Norwegian Diagnosis Related Groups system.

Epstein-Barr virus infection during pregnancy and the risk of adverse pregnancy outcome.

Objectives: To study the association between Epstein-Barr virus (EBV) antibody status in early pregnancy and pregnancy outcomes including fetal death, length of gestation and fetal weight and length at birth.

Design: Nested control study.

Setting: Population based health registers.

Maternal antibodies against cytomegalovirus in pregnancy and the risk of fetal death and low birth weight.

Background: The aim of this study was to assess the impact of maternal cytomegalovirus (CMV) antibody status in pregnancy on the risk of fetal death and of low birth weight.

Methods: The study of fetal death risk was a nested case-control study. Cases were all women within a cohort of 35,940 pregnant women in Norway 1992--94, who experienced fetal death after 16th week of gestation (n=281).

Extrahepatic bile duct atresia and viral involvement.

Several etiological factors have been suggested in the pathogenesis of extrahepatic biliary atresia (EHBA); congenital, metabolic, infectious, and multifactorial. Herein we present a study of 10 children with EHBA, the aim being to explore viral infection as a possible cause of their condition. During a period of 2 yr, all infants with EHBA were included in a study and examined on viral disease on admittance for Kasai operation.

Characterization of a recombinant type 3/type 2 poliovirus isolated from a healthy vaccinee and containing a chimeric capsid protein VP1.

A Sabin 3/Sabin 2/Sabin 3 (S3/2/3) intertypic recombinant poliovirus was isolated from a faecal specimen from a 2-year-old healthy boy approximately 12 weeks after administration of oral poliovirus vaccine. The first recombination junction was in the genomic region encoding the VP1 capsid protein between nucleotide positions 3274 and 3285 (numbering according to Sabin 3) and the second was in the RNA polymerase region (nucleotide positions 6824 and 6825). The recombination had introduced six Sabin 2-derived amino acids into the Sabin 3 capsid environment in the carboxyl terminus of VP1.

Seroepidemiology of Rickettsia africae infection in Norwegian travellers to rural Africa.

Rickettsia africae is the causative agent of African tick bite fever (ATBF), an acute febrile illness frequently accompanied by inoculation eschars, regional lymphadenitis, myalgia and severe headache. Recently, ATBF has been recognized as an emerging health problem for international travellers to rural sub-Saharan Africa. To estimate the incidence, risk factors for and proportion of symptomatic cases of travel-associated R.

[Tick-borne encephalitis in Norway].

Background: The first person reported with tick-borne encephalitis (TBE) in Norway fell ill in 1998; the second patient caught the disease in autumn 1999. Both had been to the island of Tromøy in Aust-Agder county. Searches for TBE antibodies were intensified in persons with encephalitis and a seroprevalence study was carried out.