Eurosurveillance - Volume 18, Issue 9, 28 February 2013

The norovirus (NoV) season in Denmark in late 2012 was characterised by an increase in the number of NoV infections caused mainly by the 2012 Sydney variant, but also by the 2009 New Orleans variant. Analysis of approximately 85% of the capsid gene from 10 Sydney 2012 and 9 New Orleans 2009 isolates showed rapid antigenic diversification of the Sydney 2012 variant shortly after its emergence. We also present new primers useful for transmission tracking.

We report the detection of a strain of Seoul hantavirus (SEOV) in pet rats in England and Wales. The discovery followed an investigation of a case of haemorrhagic fever with renal syndrome in Wales. Hantavirus RNA was detected via real-time reverse transcription-polymerase chain reaction (RT-PCR) and classic RT-PCR in pet rats belonging to the patient. Sequencing and phylogenetic analysis confirmed the virus to be a SEOV that is similar, but not identical, to a previously reported United Kingdom strain from wild rats.

On 21 January 2012, the Norwegian Food Safety Authority was informed about gastrointestinal illness among 111 swimming club members, who were staying at a hotel in Trondheim. A hotel dinner on 20 January was their only common meal. Kitchen staff were interviewed, and food leftovers and kitchen environment were sampled. A case was defined as a swimming team member staying at the hotel from 20 to 22 January, who fell ill with diarrhoea, abdominal pain or nausea during this period. A total of 43 cases were identified, with median duration of symptoms of 35 hours. cpe-positive Clostridium perfringens (3.8 x 10⁸ CFU), but not Bacillus cereus, was isolated from beef stew eaten by cases. cpe-negative C. perfringens was detected in a sample from the kitchen floor. SDS-PAGE showed indistinguishable protein profiles among C. perfringens cultures isolated from the beef stew, but slightly different profiles from the culture isolated from the kitchen floor. Cohort analysis showed that eating beef stew and rice was significantly associated with illness. No pathogens were detected in the rice. The temperature control of the stew, but not of the rice, was poor. Our results strongly indicate that cases were infected by Clostridium perfringens in beef stew that had inadequate temperature control during preparation.

Pertussis activity in England in 2012 was at its highest level for more than 12 years, leading to an increased number of deaths, especially among infants who were too young to be vaccinated. To support decision making on the introduction of maternal immunisation as an outbreak response measure to prevent these early deaths, we analysed reported deaths amongst infants of less than one year of age during the period from 2001 to 2011 with a capture/recapture analysis. We used log linear regression to allow for interactions. Reported deaths were obtained from the Hospital Episode Statistics for England, death registered by the Office of National Statistics and the enhanced surveillance of laboratory-confirmed pertussis conducted by the Health Protection Agency. There were a total of 48 deaths recorded; of these 41 had a disease onset before being fully protected by vaccination. Around half of these deaths (23) were recorded in all three datasets and 10 in only one. Due to the high coverage of the datasets the estimated number of deaths missed was small with 1.6 (95% confidence interval (CI): 0.5-4.5) deaths. The total average incidence was 0.721 (95% CI: 0.705-0.763) per 100,000 maternities. We concluded that under ascertainment of deaths from diagnosed pertussis cases is small. .