D Coulombier

Taking stock of the first 133 MERS coronavirus cases globally – Is the epidemic changing?

Since June 2012, 133 Middle East respiratory syndrome coronavirus (MERS-CoV) cases have been identified in nine countries. Two time periods in 2013 were compared to identify changes in the epidemiology. The case-fatality risk (CFR) is 45% and is decreasing. Men have a higher CFR (52%) and are over-represented among cases. Thirteen out of 14 known primary cases died. The sex-ratio is more balanced in the latter period. Nosocomial transmission was implied in 26% of the cases.

Rapid assessment of population size by area sampling in disaster situations

In the initial phase of a complex emergency, an immediate population size assessment method, based on area sampling, is vital to provide relief workers with a rapid population estimate in refugee camps. In the past decade, the method has been progressively improved; six examples are presented in this paper and questions raised about its statistical validity as well as important issues for further research. There are two stages. The first is to map the camp by registering all of its co-ordinates. In the second stage, the total camp population is estimated by counting the population living in a limited number of square blocks of known surface area, and by extrapolating average population calculated per block to the total camp surface. In six camps selected in Asia and Africa, between 1992 and 1994, population figures were estimated within one to two days. After measuring all external limits, surfaces were calculated and ranged between 121,300 and 2,770,000 square metres. In five camps, the mean average population per square was obtained using blocks 25 by 25 meters (625 m2), and for another camp with blocks 100 by 100 m2. In three camps, different population density zones were defined. Total camp populations obtained were 16,800 to 113,600. Although this method is a valuable public health tool in emergency situations, it has several limitations. Issues related to population density and number and size of blocks to be selected require further research for the method to be better validated.

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 1983–2013, 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 capture–recapture analysis was performed including three overlapping sources for the period 2005–2013. 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 Organizations 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.

A comparison of cluster and systematic sampling methods for measuring crude mortality

OBJECTIVE To compare the results of two different survey sampling techniques (cluster and systematic) used to measure retrospective mortality on the same population at about the same time. METHODS Immediately following a cluster survey to assess mortality retrospectively in a town in North Darfur, Sudan in 2005, we conducted a systematic survey on the same population and again measured mortality retrospectively. This was only possible because the geographical layout of the town, and the availability of a good previous estimate of the population size and distribution, were conducive to the systematic survey design. RESULTS Both the cluster and the systematic survey methods gave similar results below the emergency threshold for crude mortality (0.80 versus 0.77 per 10,000/day, respectively). The results for mortality in children under 5 years old (U5MR) were different (1.16 versus 0.71 per 10,000/day), although this difference was not statistically significant. The 95% confidence intervals were wider in each case for the cluster survey, especially for the U5MR (0.15-2.18 for the cluster versus 0.09-1.33 for the systematic survey). CONCLUSION Both methods gave similar age and sex distributions. The systematic survey, however, allowed for an estimate of the towns population size, and a smaller sample could have been used. This study was conducted in a purely operational, rather than a research context. A research study into alternative methods for measuring retrospective mortality in areas with mortality significantly above the emergency threshold is needed, and is planned for 2006.

Multidisciplinary investigation of a multicountry outbreak of Salmonella Stanley infections associated with turkey meat in the European Union, August 2011 to January 2013.

Between August 2011 and January 2013, an outbreak of Salmonella enterica serovar Stanley (S. Stanley) infections affected 10 European Union (EU) countries, with a total of 710 cases recorded. Following an urgent inquiry in the Epidemic Intelligence Information System for food- and waterborne diseases (EPIS-FWD) on 29 June 2012, an international investigation was initiated including EU and national agencies for public health, veterinary health and food safety. Two of three local outbreak investigations undertaken by affected countries in 2012 identified turkey meat as a vehicle of infection. Furthermore, routine EU monitoring of animal sources showed that over 95% (n=298) of the 311 S. Stanley isolates reported from animal sampling in 2011 originated from the turkey food production chain. In 2004–10, none had this origin. Pulsed-field gel electrophoresis (PFGE) profile analysis of outbreak isolates and historical S. Stanley human isolates revealed that the outbreak isolates had a novel PFGE profile that emerged in Europe in 2011. An indistinguishable PFGE profile was identified in 346 of 464 human, food, feed, environmental and animal isolates from 16 EU countries: 102 of 112 non-human isolates tested were from the turkey production chain. On the basis of epidemiological and microbiological evidence, turkey meat was considered the primary source of human infection, following contamination early in the animal production chain.

Refugee crisis demands European Union-wide surveillance!

The conflicts in the Middle-East and instability in Libya and some parts of Asia and Africa have resulted in a dramatic influx of refugees to the European Union (EU) in recent years. In the first nine months of 2015, more than 600,000 applications for asylum were filed in the EU [1]. With no prospect of change of the international context in the near future, it is likely that the influx of refugees into the EU will continue and may even increase in coming months.

Polio and the risk for the European Union

Martin Eichner and Stefan Brockmann warn that “Vaccinating only Syrian refugees—as has been recommended by the ECDC—must be judged as insufficient; more comprehensive measures should be taken into consideration.” In response to the recent developments regarding wild-type polio virus (WPV) circulation in Israel and a cluster of poliomyelitis cases in Syria, the European Centre for Disease Prevention and Control (ECDC) has published two risk assessments for the European Union (EU). In those assessments, we stated that European countries are currently at high risk of WPV introduction and that there are areas of low vaccination coverage at increased risk for an establishment of local transmission of WPV. Importantly, in addition to vaccinating Syrian refugees, ECDC has invited European Member States to assess their national vaccination coverage against polio (we estimate that 12 million residents in the European Union younger than 30 years are unvaccinated), detect areas at risk, and to engage in complementary action, especially among vulnerable groups living in poor sanitary conditions, recommend to travellers to areas with WPV circulation to ensure they have an updated polio vaccination status, enhance their surveillance system based on the requirements established by the Regional Certification Commission for Polio Eradication, strengthen their existing environmental and enterovirus surveillance to complement acute flaccid paralysis surveillance (with the present suboptimum quality of EU polio surveillance systems it is probable that WPV circulation is not promptly detected), assess their laboratory capacity, and to update their preparedness plans for polio outbreaks. We declare that we have no confl icts of interest.

Enhanced epidemic intelligence using a web-based screening system during the 2010 FIFA World Cup in South Africa

The 2010 FIFA World Cup took place in South Africa between 11 June and 11 July 2010. The European Centre for Disease Prevention and Control (ECDC), in collaboration with the hosting authorities, carried out enhanced epidemic intelligence activities from 7 June to 16 July 2010 for timely detection and monitoring of signals of public health events with a potential to pose a risk to participants and visitors. We adapted ECDC’s routine epidemic intelligence process to targeted event-based surveillance of official and unofficial online information sources. A set of three specifically adapted alerts in the web-based screening system MedISys were set up: potential public health events in South Africa, those occurring in the participating countries and those in the rest of the world. Results were shared with national and international public health partners through daily bulletins. According to pre-established ECDC criteria for the World Cup, 21 events of potential public health relevance were identified at local and international level. Although none of the events detected were evaluated as posing a serious risk for the World Cup, we consider that the investment in targeted event-based surveillance activities during the tournament was relevant as it facilitated real-time detection and assessment of potential threats. An additional benefit was early communication of relevant information to public health partners.

Infectious diseases prioritisation for event-based surveillance at the European Union level for the 2012 Olympic and Paralympic Games.

In 2012, London hosted the Olympic and Paralympic Games (the Games), with events occurring throughout the United Kingdom (UK) between 27 July and 9 September 2012. Public health surveillance was performed by the Health Protection Agency (HPA). Collaboration between the HPA and the European Centre for Disease Prevention and Control (ECDC) was established for the detection and assessment of significant infectious disease events (SIDEs) occurring outside the UK during the time of the Games. Additionally, ECDC undertook an internal prioritisation exercise to facilitate ECDC’s decisions on which SIDEs should have preferentially enhanced monitoring through epidemic intelligence activities for detection and reporting in daily surveillance in the European Union (EU). A team of ECDC experts evaluated potential public health risks to the Games, selecting and prioritising SIDEs for event-based surveillance with regard to their potential for importation to the Games, occurrence during the Games or export to the EU/European Economic Area from the Games. The team opted for a multilevel approach including comprehensive disease selection, development and use of a qualitative matrix scoring system and a Delphi method for disease prioritisation. The experts selected 71 infectious diseases to enter the prioritisation exercise of which 27 were considered as priority for epidemic intelligence activities by ECDC for the EU for the Games.