In August 1994, 30 of 135 (23%) bakery plant employees and over 100 people from South Wales and Bristol in the United Kingdom, were affected by an outbreak of gastroenteritis. Epidemiological studies of employees and three community clusters found illness in employees to be associated with drinking cold water at the bakery (relative risk 3·3, 95%, CI 1·6–7·0), and in community cases with eating custard slices (relative risk 19·8, 95%, CI 2·9–135·1) from a variety of stores supplied by one particular bakery. Small round-structured viruses (SRSV) were identified in stool specimens from 4 employees and 7 community cases. Analysis of the polymerase and capsid regions of the SRSV genome by reverse transcription-polymerase chain reaction (RT-PCR) demonstrated viruses of both genogroups (1 and 2) each with several different nucleotide sequences. The heterogeneity of the viruses identified in the outbreak suggests that dried custard mix may have been inadvertently reconstituted with contaminated water. The incident shows how secondary food contamination can cause wide-scale community gastroenteritis outbreaks, and demonstrates the ability of molecular techniques to support classical epidemiological methods in outbreak investigations.

Respiratory syncytial virus (RSV) infection in The Gambia occurs seasonally in association with the rainy season. This study examined the genetic variability of RSV isolates from four consecutive epidemics from 1993–6. Each epidemic was made up of a number of variants which were replaced in subsequent epidemics. Analysis of attachment (G) protein gene sequences showed that isolates were closely related to those observed in the rest of the world. However, many isolates from 1993 and 1994 were unlike other isolates observed in the developed world during this period and were more similar to isolates from 1984 in Europe. In addition, the most commonly observed genotype in the UK in the 1990s was not detected in The Gambia during this period.

Dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS) are reportable diseases, the third most common causes for hospitalization of children in Thailand. Data collected from the Ministry of Public Health were analysed for trends. Rates of DHF increased in Thailand until 1987 when the largest epidemic ever, 325/100000 population, was recorded. Whereas the disease used to be confined to large cities, the rate is now higher in rural (102·2 per 100000) than urban areas (95·4 per 100000 in 1997). The age of highest incidence has increased, and the age group most severely affected is now those 5–9 years old (679/100000 in 1997). The case fatality rate has decreased with improved treatment and is now only 0·28%.

Despite strong circumstantial evidence to suggest that the main route of TB transmission from badgers to cattle is via contaminated badger excreta, it is unclear whether the associated risks are high enough to account for the prevalence of the disease in south-west England. To decide whether this was a viable route of transmission, cattle contact with badger excreta was investigated using a deterministic approach to quantify the risks to cattle posed by badger excreta. Levels of investigative and grazing contacts between cattle and badger urine and faeces could each account for the disease prevalence in south-west England. An infection probability of 3·7×10−4 per bite from pasture contaminated with badger urine infected with Mycobacterium bovis could account for the prevalence of TB in cattle in south-west England. Infection probabilities of 6·9×10−7 per investigation and 1·1×10−7 per bite from badger latrines could each account for the prevalence of TB in cattle in the south-west. When considering only the high risk areas of south-west England these bounds fell by a factor of eight. However, badger excreta may still constitute a high level of risk to cattle. The levels of cattle contact with badger excreta are far higher than previously thought, suggesting that it is the probability of infection per given contact with infected badger excreta which has the greater influence on the probability of transmission and not the level of contact. The infection probability per cattle contact with infected badger excreta is in all likelihood extremely low.

Eighteen strains of Campylobacter sputorum bv. paraureolyticus (isolated over a 12-month period from seven dairy cows contained in a single herd) were examined by resistotyping, and macrorestriction profiling using pulsed field gel electrophoresis (PFGE). The resistotypes of these strains were identical, although repeat testing indicated resistance to metronidazole was not a reliable trait for typing purposes. Five SmaI-derived genotypes were identified among the 18 strains. In 5 of 7 cows, isolates obtained from the same animal, but from different time periods, were genotypically indistinguishable, indicating persistence of infection. Macrorestriction profiles of 5 strains representing the 5 SmaI genotypes and 8 other strains of C. sputorum from various sources, were prepared using 4 endonucleases (SmaI, SalI, BamHI and KpnI). The only other strain of C. sputorum bv. paraureolyticus examined (a Canadian isolate from human faeces), was found to have a SmaI macrorestriction profile identical with one of the five clones isolated from the cattle. Moreover, SalI and BamHI profiles of all bv. paraureolyticus strains were similar, while digestion with KpnI was not observed. By contrast, the seven strains of C. sputorum bv. sputorum yielded various macrorestriction profiles with all the enzymes used, and features distinguishing the two biovars studied could be identified. This study indicates that C. sputorum can persist in cattle for at least 12 months and exhibits a clonal population genetic structure.