Ettore Severi

Unique human immune signature of Ebola virus disease in Guinea

Despite the magnitude of the Ebola virus disease (EVD) outbreak in West Africa, there is still a fundamental lack of knowledge about the pathophysiology of EVD. In particular, very little is known about human immune responses to Ebola virus. Here we evaluate the physiology of the human T cell immune response in EVD patients at the time of admission to the Ebola Treatment Center in Guinea, and longitudinally until discharge or death. Through the use of multiparametric flow cytometry established by the European Mobile Laboratory in the field, we identify an immune signature that is unique in EVD fatalities. Fatal EVD was characterized by a high percentage of CD4+ and CD8+ T cells expressing the inhibitory molecules CTLA-4 and PD-1, which correlated with elevated inflammatory markers and high virus load. Conversely, surviving individuals showed significantly lower expression of CTLA-4 and PD-1 as well as lower inflammation, despite comparable overall T cell activation. Concomitant with virus clearance, survivors mounted a robust Ebola-virus-specific T cell response. Our findings suggest that dysregulation of the T cell response is a key component of EVD pathophysiology.

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.

Public health needs of migrants, refugees and asylum seekers in Europe, 2015: Infectious disease aspects

In the first 10 months of 2015 the total number of asylum applications to the European Asylum Support Office (EASO) recorded by European Union (EU) countries exceeded the 1 million mark, an unprecedented level since the establishment of the EU. Syria has been the most common country of origin of asylum applications, followed by Afghanistan and Iraq.1 However, these figures do not take unregistered migrants into account: in the same time period, 500 000 undocumented border crossing detections were recorded on the EU’s external borders, according to Frontex.2 In the light of these developments, the European Centre for Disease Prevention and Control (ECDC) assessed the public health needs of migrants or individuals that are applying for asylum or refugee status, through: (i) interviews with 14 experts from Member States and Non-Governmental Organizations with first-hand experience working with migrant populations (7–11 August 2015); (ii) a non-systematic review of available evidence (peer-reviewed publications and relevant ECDC risk assessments); and (c) an expert meeting on the prevention of infectious diseases among newly arrived migrants in the EU and European Economic Area (EEA) (12–13 November 2015).3–5 A recurrent theme across all the expert consultations conducted by ECDC was the need to establish a reception system for newly arrived migrants. In primary reception centres, a health assessment should be carried out immediately upon arrival. Equipping these reception areas with primary care and public health services facilitates screening, vaccination and treatment (if required) of individuals free of charge. The organisers of reception areas should consider adequately stocking them with rapid tests (e.g. for malaria) and providing instant treatment and care to patients. Such rapid interventions are the best course of action to detect and prevent onwards spread of cases of infectious disease, through the identification and management of infectious diseases with potential for …

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.

Multinational outbreak of travel-related Salmonella Chester infections in Europe, summers 2014 and 2015

Between 2014 and 2015, the European Centre for Disease Prevention and Control was informed of an increase in numbers of Salmonellaenterica serotype Chester cases with travel to Morocco occurring in six European countries. Epidemiological and microbiological investigations were conducted. In addition to gathering information on the characteristics of cases from the different countries in 2014, the epidemiological investigation comprised a matched case–case study involving French patients with salmonellosis who travelled to Morocco that year. A univariate conditional logistic regression was performed to quantify associations. The microbiological study included a whole genome sequencing (WGS) analysis of clinical and non-human isolates of S. Chester of varied place and year of isolation. A total of 162 cases, mostly from France, followed by Belgium, the Netherlands, Spain, Denmark and Sweden were reported, including 86 (53%) women. The median age per country ranged from 3 to 38 years. Cases of S. Chester were more likely to have eaten in a restaurant and visited the coast of Morocco. The results of WGS showed five multilocus sequence types (ST), with 96 of 153 isolates analysed clustering into a tight group that corresponded to a novel ST, ST1954. Of these 96 isolates, 46 (48%) were derived from food or patients returning from Morocco and carried two types of plasmids containing either qnrS1 or qnrB19 genes. This European-wide outbreak associated with travel to Morocco was likely a multi-source outbreak with several food vehicles contaminated by multidrug-resistant S. Chester strains.

Early findings in outbreak of haemolytic uraemic syndrome among young children caused by Shiga toxin-producing Escherichia coli, Romania, January to February 2016

As at 29 February 2016, 15 cases of haemolytic uraemic syndrome with onset between 25 January and 22 February were reported among children between five and 38 months in Romania, and three of them died. Cases were mostly from southern Romania. Six cases tested positive for Escherichia coli O26 by serology. Fruits, vegetables, meat and dairy products were among the possible common food exposures. Investigations are ongoing in Romania to control the outbreak.

Author's reply: measles on a cruise ship--links with the outbreak in the Philippines.

To the editor: We thank Mandal et al. for their letter in response to our paper. Firstly we would like to point out that most the concerns raised are due to the fact that our article was a preliminary report, which was also stated in the title. It was intended to rapidly inform about an outbreak of measles affecting European and non-European citizens that was ongoing at the time of publication and to alert public health, clinical and laboratory experts in various countries of the possibility of cases among people who had been on the cruise. In fact, most of those concerns are being addressed in the on-going investigation.

Community-wide outbreaks of haemolytic uraemic syndrome associated with Shiga toxin-producing Escherichia coli O26 in Italy and Romania: a new challenge for the European Union

E Severi 1 , F Vial 1 , E Peron 2 3 , O Mardh 1 , T Niskanen 1 , J Takkinen 1 1. European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden 2. European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden 3. Gastrointestinal, zoonosis and tropical diseases unit, Department of infectious diseases epidemiology, Robert Koch Institute, Berlin, Germany

Travel-associated hepatitis A in Europe, 2009 to 2015

Background Travel to countries with high or intermediate hepatitis A virus (HAV) endemicity is a risk factor for infection in residents of countries with low HAV endemicity. Aim: The objective of this study was to estimate the risk for hepatitis A among European travellers using surveillance and travel denominator data. Methods: We retrieved hepatitis A surveillance data from 13 European Union (EU)/ European Economic Area (EEA) countries with comprehensive surveillance systems and travel denominator data from the Statistical Office of the European Union. A travel-associated case of hepatitis A was defined as any case reported as imported. Results: From 2009 to 2015, the 13 countries reported 18,839 confirmed cases of hepatitis A, of which 5,233 (27.8%) were travel-associated. Of these, 39.8% were among children younger than 15 years. The overall risk associated with travel abroad decreased over the period at an annual rate of 3.7% (95% confidence interval (CI): 0.7–2.7) from 0.70 cases per million nights in 2009 to 0.51 in 2015. The highest risk was observed in travellers to Africa (2.11 cases per million nights). Cases more likely to be reported as travel-associated were male and of younger age (< 25 years). Conclusion: Travel is still a major risk factor for HAV infection in the EU/EEA, although the risk of infection may have slightly decreased in recent years. Children younger than 15 years accounted for a large proportion of cases and should be prioritised for vaccination.