Large and prolonged food-borne multistate hepatitis A outbreak in Europe associated with consumption of frozen berries, 2013 to 2014.

In May 2013, Italy declared a national outbreak of hepatitis A, which also affected several foreign tourists who had recently visited the country. Molecular investigations identified some cases as infected with an identical strain of hepatitis A virus subgenotype IA. After additional European Union/European Economic Area (EU/EEA) countries reported locally acquired and travel-related cases associated with the same outbreak, an international outbreak investigation team was convened, a European outbreak case definition was issued and harmonisation of the national epidemiological and microbiological investigations was encouraged. From January 2013 to August 2014, 1,589 hepatitis A cases were reported associated with the multistate outbreak; 1,102 (70%) of the cases were hospitalised for a median time of six days; two related deaths were reported. Epidemiological and microbiological investigations implicated mixed frozen berries as the vehicle of infection of the outbreak. In order to control the spread of the outbreak, suspected or contaminated food batches were recalled, the public was recommended to heat-treat berries, and post-exposure prophylaxis of contacts was performed. The outbreak highlighted how large food-borne hepatitis A outbreaks may affect the increasingly susceptible EU/EEA general population and how, with the growing international food trade, frozen berries are a potential high-risk food.

Food-borne diseases associated with frozen berries consumption: a historical perspective, European Union, 1983 to 2013.

Epidemiological investigations of outbreaks of hepatitis A virus (HAV) and norovirus (NoV) infections in the European Union/European Economic Area (EU/EEA) in the last five years have highlighted frozen berries as a vehicle of infection. Given the increasing berry consumption in the EU over the last decades, we undertook a review of the existing evidence to assess the potential scale of threat associated with this product. We searched the literature and four restricted-access online platforms for outbreak/contamination events associated with consumption of frozen berries. We performed an evaluation of the sources to identify areas for improvement. The review revealed 32 independent events (i.e. outbreak, food contamination) in the period 1983­2013, of which 26 were reported after 2004. The identified pathogens were NoV, HAV and Shigella sonnei. NoV was the most common and implicated in 27 events with over 15,000 cases reported. A capture­recapture analysis was performed including three overlapping sources for the period 2005­2013. The study estimated that the event-ascertainment was 62%. Consumption of frozen berries is associated with increasing reports of NoV and HAV outbreaks and contamination events, particularly after 2003. A review of the risks associated with this product is required to inform future prevention strategies. Better integration of the available communication platforms and databases should be sought at EU/EEA level to improve monitoring, prevention and control of food-borne-related events.

Changing hepatitis A epidemiology in the European Union: new challenges and opportunities.

This perspective on hepatitis A in the European Union and European Economic Area (EU/EEA) presents epidemiological data on new cases and outbreaks and vaccination policies. Hepatitis A endemicity in the EU/EEA ranges from very low to intermediate with a decline in notification rates in recent decades. Vaccination uptake has been insufficient to compensate for the increasing number of susceptible individuals. Large outbreaks occur. Travel increases the probability of introducing the virus into susceptible populations and secondary transmission. Travel medicine services and healthcare providers should be more effective in educating travellers and travel agents regarding the risk of travel-associated hepatitis A. The European Centre for Disease Prevention and Control (ECDC) endorses the World Health Organization's recommendations on vaccination of high-risk groups in countries with low and very low endemicity and on universal vaccination in countries with intermediate endemicity. Those recommendations do not cover the use of hepatitis A vaccine to control outbreaks. ECDC together with EU/EEA countries should produce evidence-based recommendations on hepatitis A immunisation to control outbreaks. Data about risk behaviours, exposure and mortality are scarce at the EU/EEA level. EU/EEA countries should report to ECDC comprehensive epidemiological and microbiological data to identify opportunities for prevention.

Three simultaneous, food-borne, multi-country outbreaks of hepatitis A virus infection reported in EPIS-FWD in 2013: what does it mean for the European Union?

Between March and May 2013, three multi-country outbreaks of hepatitis A virus (HAV) infection were reported through the Epidemic Intelligence Information System for Food- and Water-borne diseases (EPIS-FWD) of the European Centre for Disease Prevention and Control (ECDC). The aim of this work is to put these outbreaks into a European Union (EU) and European Economic Area (EEA) perspective and highlight opportunities for improving detection and investigation of such outbreaks. Although HAV outbreaks are not unusual in the EU/EEA, having three large food-borne multi-country outbreaks declared within three months is an unexpected event, particularly when at least two of these outbreaks are associated with frozen berries. Factors influencing the occurrence of these events include the increased number of susceptible Europeans, the limited coverage of HAV vaccination, the global trade of potentially contaminated products introduced in the EU/EEA, and the 'awareness chain effect' leading to a wave of notifications. Further studies should be conducted to understand the risk posed by frozen berries. Laboratory capacity and surveillance of viral infections in the EU/EEA, as well as HAV vaccination recommendations to travellers to endemic countries should be strengthened. Finally, timely reporting food-borne events through EPIS-FWD, to ensure timely response.

Evaluation of the Health Protection Event-Based Surveillance for the London 2012 Olympic and Paralympic Games.

The Health Protection Agency (HPA) (currently Public Health England) implemented the Health Protection Event-Based Surveillance (EBS) to provide additional national epidemic intelligence for the 2012 London Olympic and Paralympic Games (the Games). We describe EBS and evaluate the system attributes. EBS aimed at identifying, assessing and reporting to the HPA Olympic Coordination Centre (OCC) possible national infectious disease threats that may significantly impact the Games. EBS reported events in England from 2 July to 12 September 2012. EBS sourced events from reports from local health protection units and from screening an electronic application 'HPZone Dashboard' (DB). During this period, 147 new events were reported to EBS, mostly food-borne and vaccine-preventable diseases: 79 from regional units, 144 from DB (76 from both). EBS reported 61 events to the OCC: 21 of these were reported onwards. EBS sensitivity was 95.2%; positive predictive value was 32.8%; reports were timely (median one day; 10th percentile: 0 days - same day; 90th percentile: 3.6 days); completeness was 99.7%; stability was 100%; EBS simplicity was assessed as good; the daily time per regional or national unit dedicated to EBS was approximately 4 hours (weekdays) and 3 hours (weekends). OCC directors judged EBS as efficient, fast and responsive. EBS provided reliable, reassuring, timely, simple and stable national epidemic intelligence for the Games.

Measles outbreak on a cruise ship in the western Mediterranean, February 2014, preliminary report.

A measles outbreak occurred in February 2014 on a ship cruising the western Mediterranean Sea. Overall 27 cases were reported: 21 crew members, four passengers.For two cases the status crew or passenger was unknown. Genotype B3 was identified. Because of different nationalities of cases and persons on board,the event qualified as a cross-border health threat. The Italian Ministry of Health coordinated rapid response.Alerts were posted through the Early Warning and Response System.

Timeliness of electronic reporting and acceptability of public health follow-up of routine nonparatyphoidal and nontyphoidal Salmonella infections, London and South East England, 2010 to 2011.

Nonparatyphoidal and nontyphoidal Salmonella (NTS) infections are major causes of food poisoning in England. Diagnostic laboratories and clinicians have a statutory responsibility to report NTS infection cases to the Health Protection Agency via various means, with electronic reporting encouraged as the universal method. The Health Protection Agency (Public Health England since 1 April 2013) refers cases to environmental health departments for follow-up. Timeliness of reporting and adequacy of NTS infection case follow-up are key factors in the implementation of public health actions. Laboratories, health protection units, and environmental health departments in London and South East (SE) regions of England completed three surveys between December 2010 and April 2011, collecting data about the NTS infection case reporting methods and the time elapsed between symptom onset and public health actions. The median period between symptom onset and public health investigation was 25 days in London and 23 days in SE when electronic reporting was used and 12 days in London and 11 days in SE when other means of reporting were used. The most common follow-up method was a telephone questionnaire in London (53%) and a postal questionnaire in SE (52%). The telephone questionnaire had the highest response rate (98% in London; 96% in SE). Timeliness and efficiency of electronic NTS infection case reports can be improved by decreasing the electronic laboratory report period and using telephone-administered questionnaires to maximize the public health benefit when following up single cases of NTS infection.

Infectious disease surveillance for the London 2012 Olympic and Paralympic Games.

The London 2012 Olympic and Paralympic Games will be one of the largest mass gathering events in British history. In order to minimise potential infectious disease threats related to the event, the Health Protection Agency (HPA) has set up a suite of robust and multisource surveillance systems. These include enhancements of already established systems (notification of infectious diseases, local and regional reporting,laboratory surveillance, mortality surveillance, international surveillance, and syndromic surveillance in primary care), as well as new systems created for the Games (syndromic surveillance in emergency departments and out-of-hours/unscheduled care,undiagnosed serious infectious illness surveillance).Enhanced existing and newly established surveillance systems will continue after the Games or will be ready for future reactivation should the need arise. In addition to the direct improvements to surveillance, the strengthening of relationships with national and international stakeholders will constitute a major post-Games legacy for the HPA.

Large outbreak of Salmonella enteritidis PT8 in Portsmouth, UK, associated with a restaurant.

Seventy-five individuals with Salmonella infection were identified in the Portsmouth area during August and September 2009, predominantly Salmonella Enteritidis phage type 8. Five patients were admitted to hospital. A case-case comparison study showed that a local restaurant was the most likely source of the infection with a risk of illness among its customers 25-fold higher than that of those who did not attend the restaurant. A case-control study conducted to investigate specific risk factors for infection at the restaurant showed that eating salad was associated with a threefold increase in probability of illness. Changing from using ready washed lettuces to lettuces requiring washing and not adhering strictly to the 48 hours exclusion policy for food handlers with diarrhoea were likely to have contributed to the initiation and propagation of this outbreak. Possibilities for cross-contamination and environmental contamination were identified in the restaurant.

The Escherichia coli AmtB protein as a model system for understanding ammonium transport by Amt and Rh proteins.

The Escherichia coli ammonium transport protein (AmtB) has become the model system of choice for analysis of the process of ammonium uptake by the ubiquitous Amt family of inner membrane proteins. Over the past 6 years we have developed a range of genetic and biochemical tools in this system. These have allowed structure/function analysis to develop rapidly, offering insight initially into the membrane topology of the protein and most recently leading to the solution of high-resolution 3D structures. Genetic analysis has revealed a novel regulatory mechanism that is apparently conserved in prokaryotic Amt proteins and genetic approaches are also now being used to dissect structure/function relationships in Amt proteins. The now well-recognised homology between the Amt proteins, found in archaea, eubacteria, fungi and plants, and the Rhesus proteins, found characteristically in animals, also means that studies on E. coli AmtB can potentially shed light on structure/function relationships in the clinically important Rh proteins.