This report describes the epidemiology, investigation and control of a hepatitis A (HAV) outbreak in New Zealand. Descriptive and analytical epidemiology, virology, product traceback and an orchard investigation were carried out. A case–control study revealed that 56% of 39 cases had consumed raw blueberries, compared with 14% of 71 controls (odds ratio 7·6; 95% confidence intervals 2·6–22·4). Traceback of product through retailers and wholesalers implicated a single commercial orchard. Hepatitis A virus was detected by reverse transcriptase polymerase chain reaction in faecal specimens from cases as well as a blueberry product from the orchard. Presence of hepatitis A virus was confirmed by DNA hybridization and sequencing of PCR products. Sanitary audit of the orchard revealed multiple opportunities for contamination of blueberries by pickers. This outbreak highlights the need for food safety programmes in the berry fruit industry.

Untreated waste water usage in agriculture is an important health-threatening issue which could affect both workers' and the public's health. In this study we researched hepatitis E infection in 46 of 57 farmers who used untreated waste water in agriculture. We compared them with 45 persons of the same socio-economic status and age. Anti-HEV seropositivity was 34·8% in the workers and 4·4% in the control group. We suggest that this type of irrigation is an important potential risk for hepatitis E infection.

A community-based seroepidemiological survey of Addis Ababa, Ethiopia was conducted in 1994 to inform on the transmission dynamics and control of hepatitis B virus (HBV) infection. Venous blood from 4736 individuals under 50 years of age from 1262 households, selected using stratified cluster-sampling, was screened for HBV markers using commercial ELISAs. HBsAg prevalence was 7% (95% CI 6–8), higher in males (9%; 7–10) than females (5%; 4–6). HBeAg prevalence in HBsAg positives was 23% (18–29), and less than 1% of women of childbearing age were HBeAg positive. Overall HBV seroprevalence (any marker), rose steadily with age to over 70% in 40–49 year olds, indicating significant childhood and adult transmission. Estimated instantaneous incidence was 3–4/100 susceptibles/year, higher in males than females in 0–4 year olds, and peaking in early childhood and young adults. The age at which 50% had evidence of infection was around 20 years, and the herd immunity threshold is approximated at 63–77%. Addis Ababa is of intermediate-high HBV endemicity, with negligible perinatal transmission. Our main findings are the identification of a significant difference between males and females in the age-acquisition of HBV infection, and marked differences between age groups in HBV incidence rates. These results should target future research studies of underlying risk factors. Furthermore, we generate a crude estimate of the level of coverage of HBV vaccine that would be required to eliminate the virus from the study population.

It is generally believed that hepatitis B (HBV) and C (HCV) viruses are highly prevalent in the Republic of Yemen. This study investigated the prevalence of HBV and HCV markers in 494 blood donors from Aden, 493 blood donors from Sana'a, 97 residents from an African ethnic minority in Sana'a and 99 residents of Soqotra Island. There were significant differences in the prevalence of HBV carriage (HBsAg: 6·7, 15, 19·6 and 26·3% respectively; P<0·001); past HBV infection (anti-HBc: 17·4, 18·5, 30·9 and 59·6% respectively; P<0·001); susceptibility to HBV (absence of HBV markers: 73·3, 61·9, 38·1 and 9·1% respectively; P<0·001), infectivity of HBV carriers (HBV DNA: 51·5, 33·8, 52·6 and 65·4% respectively; P=0·028) and HCV antibodies (RIBA confirmed or indeterminate: 0·6, 0·2, 5·2 and 5·1% respectively; P<0·001). A significant difference in HBV carrier rate and a borderline significant difference in the prevalence of natural infection was observed between males and females in the African community (P=0·02 and 0·06 respectively). In contrast, in Soqotra Island, there was no significant sex difference in HBV carrier rate but susceptibility was significantly more prevalent in males (P=0·03). This study illustrates that significant difference in prevalence and epidemiology exists among different communities within the same country, reflecting political, geographical and social differences. Control strategies should take these differences into account.

A molecular epidemiological study of 48 recent rabies isolates recovered from cases reported throughout Iran identified three distinct viral variants, the evolutionary origins of which were identified by phylogenetic comparison with rabies viruses originating from Europe and Asia. Members of group 1 (15 isolates) were recovered from the northern half of the country only, while those of group 2 (31 isolates) were widely dispersed; both groups clustered within the widely disseminated cosmopolitan lineage. The two isolates of group 3 were detected in the northeastern tip of the country only and belonged to the Arctic strain. Rapid variant discrimination tools, employing restriction fragment length polymorphisms applied to amplified fragments of the viral genome, were devised whilst antigenic characterization of representative viruses identified a small panel of monoclonal antibodies that were also discriminatory. The future application of such methods should provide valuable epidemiological information on rabies incidence in Iran.

Migrants from Java arrive in hyperendemic Papua, Indonesia lacking exposure to endemic malaria. We evaluated records of evacuation to hospital with a diagnosis of severe malaria from a transmigration village in northeastern Papua. During the first 30 months, 198 residents with severe disease were evacuated (7·5 evacuations/100 person-years). During this period the risk of evacuation for adults (>15 years of age) was 2·8. (95% CI=2·1–3·8; P<0·0001) relative to children, despite apparently equal exposure to risk of infection. Relative risk (RR) for adults was greatest during the first 6 months (RR>16; 95% CI[ges ]2·0–129; P=0·0009), and diminished during the second 6 months (RR=9·4; 95% CI=2·7–32·8; P<0·0001) and the third 6 months (RR=3·7; 95% CI=1·7–7·9; P=0·0004). During the next two 6-month intervals, the RR for adults was 1·6 and 1·5 (95% CI range 0·8–2·6; P<0·18). Adults lacking chronic exposure were far more likely to progress to severe disease compared to children during initial exposure, but not after chronic exposure to infection.

We examined the risk factors for bacterial exacerbation, defined as the presence of pathogenic bacteria in sputum, in 90 chronic obstructive pulmonary disease (COPD) patients with an exacerbation and changes in sputum characteristics. Smoking, alcohol, lung function, body mass index, medical visits and treatments were the independent variables assessed using multivariable logistic regression modelling (OR, 95% CI). A bacterial exacerbation was diagnosed in 39 (43·3%) of 90 patients. Bacterial exacerbations were more prevalent among current smokers (OR 3·77, 95% CI 1·17–12·12), in patients with poor compliance with inhalation therapy (OR 3·25, 95% CI 1·18–8·93) and with severe lung function impairment (FEV1 OR 0·96, 95% CI 0·93-1·00). Prior use of antibiotics was a risk factor for Pseudomonas aeruginosa infection (OR 6·06, 95% CI 1·29–28·44) and influenza vaccination appeared to have a protective effect against this infection (OR 0·15, 95% CI 0·03–0·67). We conclude that severe impairment of lung function, smoking and poor compliance with therapy are risk factors for bacterial infection in COPD, and P. aeruginosa should be suspected in patients who have been treated with antibiotics and in those not vaccinated against influenza.

During the late production stages, a spelling mistake was introduced into the title of a recent article in Epidemiology and Infection by P. E. Carter, K. Begbie and F. M. Thomson-Carter [Epidemiol. Infect. (2003), 130, 207–219 DOI: 10.1017/S0950268802008038]. The correct title should be: Coagulase gene variants associated with distinct populations ofStaphylococcus aureus.

We apologise to the authors and readers for this error.