The seroprevalence of hepatitis B, C and D markers was assessed in a sample of 670 Albanian refugees in Southern Italy in 1997. The mean age was 25 years (S.D. = 12·3). Of study subjects 62·1% (95% CI: 58·4–65·7) were positive for anti-HBc antibodies and 13·6% (95% CI: 10·9–16·1) for HBsAg. The prevalence of anti-HBs was 47·6% (95% CI: 43·8–51·3). Among HBsAg carriers the prevalence of HBeAg was 7·7% (95% CI: 2·2–13·1). The highest carrier rate for HBsAg (25·5%; 95% CI: 16·7–34·3) was found in the age group 21–25 years. A relevant finding was a prevalence of HBsAg of 8·1% in children 10 years and under. The prevalence of anti-HCV antibodies was 0·3% (95% CI: 0·0–0·7) while only one of the HBsAg carriers was positive for anti-HDV (1·1%, 95% CI: 0–3·2). In Albania, hepatitis B infection represents a public health priority that should be addressed by a universal vaccination campaign.

Hepatitis B Virus (HBV) e antigen (HBeAg), HBV DNA and precore mutations affecting HBeAg expression during active replication were studied in 72 Tunisian hepatitis B surface antigen (HBsAg) positive individuals: 30 asymptomatic carriers of the virus, 37 with chronic hepatitis and 5 with acute hepatitis. HBV DNA was detected in 44 patients, but only 20% of them expressed HBeAg. Precore mutant strains, with mutations at position 1896 or at positions 1896 and 1899, were detected by PCR-hybridization in 86 and 36% of patients, respectively. Wild-type strains were detected in 54% of patients. Precore mutants were found in chronically and in acutely infected individuals, in patients with severe and asymptomatic infections, in HBeAg positive as well as HBeAg negative individuals. These results show the high frequency of HBV precore mutants in Tunisia.

Human rabies is known to be endemic in countries bordering Lebanon, but its prevalence in Lebanon has not been studied before. All eight cases of human rabies reported to the Lebanese Ministry of Public Health between 1991 and 1999 were reviewed, as well as three other cases admitted to the American University of Beirut Medical Center. A total of 1102 cases of animal bites to humans, the majority of which were dog bites, were reported to the Ministry of Public Health between 1991 and 1996. In this period, 2487 doses of rabies vaccine were administered to the above group, as post-exposure prophylaxis. Veterinarians, a high risk and educated group, were interviewed, and only 7 out of 72 were found to have been vaccinated. Major improvements in surveillance and reporting, better control of animal rabies, more awareness especially among high risk groups, and regional cooperation, are all needed to prevent and control this deadly infection.

A St. Louis encephalitis (SLE) epidemic in Florida during 25 weeks in 1990–1, resulted in 222 laboratory-diagnosed cases, an attack rate in the 28 affected counties of 2·25/100000. Disease risk rose with advanced age, to 17·14/100000 in persons over 80 years, and all 14 fatal cases were in persons over 55 years (median, 70 years). Community serosurveys in Indian River County, the epicenter of the outbreak (attack rate 21/100000), showed acute asymptomatic infections in 3·6% of the persons surveyed, with higher rates in persons with outdoor occupational exposure (7·4%) and in clients of a shelter for the indigent (13·3%). A matched case-control study found that evening outdoor exposure for more than 2 h was associated with an increased risk for acquiring illness (odds ratio [OR] 4·33, 95% CI 1·23–15·21) while a number of recommended personal protective measures were protective. Four SLE patients were dually infected with Highlands J virus, the first reported cases of acute infection with this alphavirus. The case-control study provided the first evidence that a public education campaign to reduce exposure had a protective effect against acquiring the disease.

Surveillance of dengue fever is mainly based on specific laboratory tests. However non-specific systems, such as clinical surveillance, are also required. In French Guiana, we have tested a non-specific laboratory surveillance system where different biological examinations performed for other reasons than the diagnosis of dengue fever were analysed as methods for dengue fever surveillance. The number of negative malaria diagnoses in Cayenne and Kourou was found to be the best indicator of dengue fever infections in these towns. This surveillance system appears to be very simple and reliable, and a test which could serve as an indicator that is likely to be found everywhere.

Dengue fever (DF) or dengue haemorrhagic fever (DHF) has not previously been reported in Coimbatore and Erode districts in Tamil Nadu in India. In 1998, 20 hospitalized cases of fever tested positive for dengue virus IgM and/or IgG antibodies. All of them had dengue-compatible illness, and at least four had DHF. Two of them died. Sixteen cases were below 10 years of age. The cases were scattered in 15 distantly located villages and 5 urban localities that had a high Aedes aegypti population. Although the incidence of dengue-like illness has not increased recently, almost 89% (95/107) of samples from healthy persons in the community tested positive for dengue IgG antibodies. The study showed that dengue has been endemic in the area, but was not suspected earlier. A strong laboratory-based surveillance system is essential to monitor and control DF/DHF.

A total of 65 cases of Creutzfeldt–Jakob disease with a history of cadaveric dura transplantation in Japan were analysed to clarify the epidemiologic features of such patients and to explore whether other such patients will appear in the future. The age at transplantation averaged 44·4 years with a standard deviation of 14·4 years. The age at onset had an average of 53·0 years with a standard deviation of 14·1 years. The shortest latent period was 14 months, and the longest was 218 months with an average of 103·1 months and a standard deviation of 49·9 months. From the relationship between the calendar year at transplantation and the latent period, other such patients will appear in the near future. The current data suggested that several patients with Creutzfeldt–Jakob disease will occur from those receiving cadaveric dura mater grafts in the near future.

Control programmes have reduced the prevalence of Bancroftian filariasis in Thailand to low levels. Recently, there has been an influx of more than one million Myanmar immigrants into urban centres of Thailand. The prevalence of patent Wuchereria bancrofti infection in these immigrants (2–5%) has prompted concern in the public health community that the potential now exists for a re-emergence of Bancroftian filariasis in Thailand. It is possible that an urban cycle of transmission could become established. The Myanmar immigrants are infected with the nocturnal periodic (urban) type W. bancrofti for which Culex quinquefasciatus serves as the main vector. The Thai strains of Cx. quinquefasciatus have never been reported to transmit Bancroftian filariasis. Our results of feeding experiments demonstrated that the Thai Cx. quinquefasciatus are permissive for the development of Myanmar W. bancrofti to infective third-stage larvae thus establishing the potential for establishing an urban cycle of transmission in Thailand. We also adapted the SspI repeat PCR assay for the identification of infective mosquitoes that was capable of detecting a single infective stage larvae in a pool of 100 mosquitoes.

In this work, we applied the random amplified polymorphic DNA (RAPD) technique to evaluate the genetic diversity in Photobacterium damselae subsp. piscicida (formerly Pasteurella piscicida), an important pathogen for different marine fish. Regardless of the oligonucleotide primer employed, the 29 isolates of Ph. damselae subsp. piscicida tested were separated into two groups, the RAPD-PCR analysis differentiated the European strains from the Japanese strains. The similarity between both groups estimated on the basis of the Dice coefficient was 75–80%. These results show that European and Japanese isolates of Ph. damselae subsp. piscicida, regardless of their host fish species, belong to two different clonal lineages. Our findings also indicate that RAPD profiling constitutes a useful tool for epidemiological studies of this fish pathogen.

Escherichia coli O157 isolates from cattle in Japan (n = 91) and in the USA (n = 415) were compared by pulsed-field gel electrophoresis of endonuclease-cleaved genomic DNA, location of the stx genes and bacteriophage typing. Three isolates from cattle in Japan with high similarity to isolates from cattle in the USA were found. Isolates from cattle farms in Japan and the USA may share a common source.

Epidemiol. Infect.124 (2000), 61–7

Occurrence ofClostridium perfringensβ2-toxin amongst animals, determined using genotyping and subtyping PCR assays

Page 61, Summary, line 7, should read:

‘… and the gene encoding β2-toxin was …’