To evaluate whether or not human herpesvirus 8 (HHV8) can be transmitted through a non-sexual route a serological survey was carried out in a group of 51 catholic nuns. The seroprevalence rate and the geometrical mean antibody titre to anti-latent HHV8 antigen were similar in nuns and in a group of 60 women, matched by age, in the general population (27 vs. 24%; 1028 vs. 1575, respectively). Moreover, by using nested polymerase chain reaction (PCR), HHV8 DNA sequences were detected in 7 of 16 (43·8%) saliva and peripheral blood mononuclear cells (PBMC) from patients with classical Kaposi's sarcoma (KS) and in 3 out of 7 (42%) AIDS-KS patients. None of 5 HIV positive persons who did not have KS tested positive for HHV8 DNA. HHV8 DNA sequences were also detected in 2 of 12 (17%) saliva and 1 PBMC sample out of 12 healthy HHV8 positive individuals (age range: 30–80 years old). This paper suggests that non-sexual transmission of HHV8 is operating in our geographical setting and saliva may be a potential source of HHV8 spreading in the general population.

Over a 14-year period (1984–97) the presence of rotavirus in stool samples from children under 15 years with acute gastroenteritis was studied by enzymoimmunoanalysis. Serotyping (G1–G4) was performed using monoclonal antibodies. A total of 17348 children under 15 were investigated. Rotavirus was detected in 3637 (21·0%) specimens, 74·6% of which were from children younger than 2 years old. G1 and G4 were the most frequent serotypes. In 1991–7, the minimum incidence of rotavirus gastroenteritis in children under 4 years of age was 21·7 cases/1000 children/year. By the age of 5 years, at least 1 out of 11·3 children and probably 1 out of every 5–6 children in this area had experienced an episode of rotavirus gastroenteritis that required medical care. In the 1984–90 period a clear seasonality was not observed but in the second period of the study (1991–7), seasonality was marked, with peak activity in winter.

In this study the impact of pregnancy duration on the measured level of HSV-2 antibodies was assessed. The study population comprised 35940 pregnant women in Norway, in 1992–4, followed during pregnancy. A random sample of 960 women was selected. A mean of 2·6 serum samples from each woman were analysed for HSV-2 specific IgG antibodies at different times in pregnancy. Crude and adjusted odds ratios were estimated in logistic regression models taking all observations per women into account. Twenty-seven percent of the pregnant women had antibodies against HSV-2 in the first trimester. The adjusted odds ratio of being HSV-2 antibody positive decreased during the pregnancy and was 0·5 (0·2–0·9, 95% confidence interval) in the 40th as compared to the 10th week of pregnancy. About 50% of initially HSV-2 positive women did not have detecable antibodies by the end of the pregnancy. This may be explained by haemodilution during pregnancy. Our findings have diagnostic implications and should encourage further studies.

Most outbreaks of viral hepatitis in India are caused by hepatitis E. This report describes an outbreak of hepatitis B in a rural population in Haryana state in 1997. At least 54 cases of jaundice occurred in Dhottar village (population 3096) during a period of 8 months; 18 (33·3%) of them died. Virtually all fatal cases were adults and tested positive for HBsAg (other markers not done). About 88% (21/24) of surviving cases had acute or persistent HBV/HCV infections; 54% (13/24) had acute hepatitis B. Many other villages reported sporadic cases and deaths. Data were pooled from these villages for analysis of risk factors. Acute hepatitis B cases had received injections before illness more frequently (11/19) than those found negative for acute or persistent HBV/HCV infections (3/17) (P = 0·01). Although a few cases had other risk factors, these were equally prevalent in two groups. The results linked the outbreak to the use of unnecessary therapeutic injections.

The aim of this study was to estimate the prevalence of hepatitis B exposure in the population of the Republic of Ireland, by measuring the prevalence of hepatitis B anti-core antibody in oral fluid collected by postal survey.

A random multi-stage stratified sample of Irish households was obtained, using the Irish electoral register as the sampling frame. A total of 962 households were selected, and a household response rate of 60·4% was achieved. Oral fluid specimens totalling 1714 were tested for antibody to hepatitis B core antigen (anti-HBc), using an Immune Capture Enzyme Immuno-Assay. Five specimens (0·29%) were found to contain anti-HBc. Adjusting for study design, the estimated anti-HBc prevalence in the Republic of Ireland is 0·51%.

This study demonstrates that self-collection of oral fluid samples is acceptable to the public, and based upon the data generated, that the Republic of Ireland has a low prevalence of hepatitis B infection.

The prevalence and genetic diversity of hepatitis C infection in women attending antenatal clinics in two regions of England was investigated to inform future surveillance and control measures. Women booking into antenatal care are routinely offered a test for immunity to rubella. Serum residues from these tests were unlinked, anonymized and archived as part of the Unlinked Anonymous Prevalence Monitoring Programme (UAPMP). The serum specimens were tested for anti-HCV using a cost-effective pooling strategy. After taking into account differential sampling from the UAPMP serum archive, the adjusted overall prevalence of anti-HCV was 0·43% (95% CI: 0·32–0·53) in London and 0·21% (95% CI: 0·14–0·28) in the Northern and Yorkshire region. Restriction fragment length polymorphism of amplified HCV RNA identified type 3a as the most common HCV genotype in these antenatal women. The prevalence of anti-HCV in antenatal women in the UK is low and consistent with that expected from injecting drug use.

Cryptosporidiosis is the most common cause of outbreaks of disease linked to mains water supply in the United Kingdom and the second commonest in the United States. Recent evidence has suggested that prior population immunity may have an impact on the epidemiology of waterborne outbreaks and in particular prior immunity may reduce the power of case-control studies for demonstrating association between disease and water consumption behaviour. However, the degree of impact of prior immunity on the power of epidemiological studies is not yet clear. This paper reports the results of some simple mathematical models of outbreaks of waterborne disease in populations with varying levels of immunity due to prior water and non-water exposure. The basic outbreak model was run on a spreadsheet. To determine the impact of prior immunity on case-control studies, further analysis was done using a Monte Carlo method to simulate sampling from cases and controls. It was found that moderate degrees of prior immunity due to water associated disease could markedly reduce the relative risk of water consumption on illness in waterborne outbreaks. In turn this would reduce the power of case-control studies. In addition, this model was used to demonstrate the impact of case misclassification and recall bias on case-control studies. Again it was found that within the model, the results of case-control studies could be significantly affected by both these sources of error. Anyone conducting epidemiological investigations of potentially waterborne outbreaks of disease should be aware of the epidemiological problems. Mistakes from case-control studies will be minimized if the outbreak team pays considerable attention to the descriptive phase of the investigation and if case-control studies are conducted as soon as possible after an outbreak is detected.

We studied the seroprevalence of three viruses (mouse cytomegalovirus (MCMV), minute virus of mice (MVM), and mouse parvovirus (MPV)) in house mice (Mus domesticus) in 1995–7. In the first year average mouse density was less than 1 mouse/ha. From November 1995 to May 1996 the population increased at an average rate of 7% per week, a doubling time of about 10 weeks. From August 1996 to May 1997 the population increased at an average rate of 10% per week, a doubling time of about 7·5 weeks. From a peak around 250 mice/ha in May 1997, the mouse population fell 19% per week to 5 mice/ha in October 1997. The seroprevalence for all three viruses varied dramatically over time. MCMV had the highest seroprevalence (61·7%), followed by MVM (8·5%) and MPV (18·4%). Time series data indicated that MCMV spread rapidly through the population of mice once trap success was greater than 14% (40–100 mice/ha). By contrast MVM and MPV seroprevalence occurred with a 2–3 month and 3–4 month time lag, respectively. The current study supports the contention that MCMV would be a good carrier for an immunocontraceptive vaccine for controlling field populations of mice.

Partial nucleotide sequence at the 3′ end of 1D (VP1-encoding) gene of 90 foot-and-mouth disease virus type O isolates recovered from field outbreaks in India between 1993–9 were determined. The sequences were compared with each other and reference viruses. The published sequences of 15 type O isolates recovered from different parts of Asia and one isolate (O1BFS) from Europe and one from Egypt (O1/Sharquia/Egypt/72) were also included in the analysis for comparison. On the basis of phylogenetic analysis the viruses could be grouped into four distinct genotypes (genotypes I–IV). All 90 isolates from India were genotype-I, as were the reference isolates from Bangladesh, China, Egypt, Iran, Saudi Arabia, Syria and Turkey. Genotype-I isolates were further subdivided into 16 sub-genotypes. The Indian isolates were found to be extremely heterogeneous in nature and clustered into 12 different genetic groups. In genotype-I, the nucleotide sequence difference seen between the isolates was 0–11·6%, while among the Indian isolates it is 0–8·8%. Viruses of similar genetic groups are circulating in India, Bangladesh and countries of the Middle East. Genotype-II and -III are represented by isolates from Lebanon (O1/South Lebanon) and Europe (O1-BFS), respectively. Genotype-IV is formed by isolates from China, Hong Kong and Taiwan. The present study reveals the occurrence of viruses belonging to multiple genetic groups over a short period of time and persistence of single genetic group in the same geographical area over several years. This is consistent with the endemic nature of the disease in the country.