Increasing Incidence of Listeriosis in France and Other European Countries

The cause of an increase among persons >60 years of age in France is unknown

Influenza vaccination coverage against seasonal and pandemic influenza and their determinants in France: a cross-sectional survey

BACKGROUND: Following the emergence of the influenza A(H1N1)2009 virus, the French ministry of health decided to offer free vaccination against pandemic influenza to the entire French population. Groups of people were defined and prioritised for vaccination. METHODS: We took a random sample of the population of mainland France and conducted a retrospective cross-sectional telephone survey to estimate vaccination coverage against seasonal and pandemic influenza and to identify determinants of these vaccinations. RESULTS: 10,091 people were included in the survey. Overall seasonal influenza vaccination coverage (IVC) remained stable in the population from the 2008-2009 season to the 2009-2010 season reaching 20.6% and 20.8% respectively. Overall pandemic IVC in the French population is estimated to be 11.1% (CI95%: 9.8 - 12.4). The highest pandemic IVC was observed in the 0-4 years age group. For individuals with health conditions associated with higher risk of influenza, pandemic IVC was estimated to be 12.2% (CI95%: 9.8 - 15.1). The main determinants associated with pandemic influenza vaccine uptake were: living in a household with a child < 5 years OR(adj): 2.0 (CI95%: 1.3 - 3.1) or with two children < 5 years or more, OR(adj): 2.7 (CI95%: 1.4 - 5.1), living in a household where the head of the family is university graduate (>2 years), OR(adj): 2.5 (CI95%: 1.5 - 4.1), or has a higher professional and managerial occupation, OR(adj): 3.0 (CI95%: 1.5 - 5.5) and being vaccinated against seasonal influenza, OR(adj): 7.1 (CI95%: 5.1 - 10.0). Being an individual with higher risk for influenza was not a determinant for pandemic influenza vaccine uptake. These determinants are not the same as those for seasonal influenza vaccination. CONCLUSIONS: Overall A(H1N1)2009 influenza vaccine uptake remained low, particularly among individuals with higher risk for influenza and was lower than that observed for seasonal influenza. The reasons behind people's reluctance to be vaccinated need to be investigated further

Dengue virus infections among European travellers, 2015 to 2019

Background: Dengue is a disease with major impacts on public health in tropical and subtropical countries. In Europe, in the past decade, few autochthonous outbreaks were described. Aim: We aimed to identify factors associated with frequency of dengue virus infection among European travellers and at assessing how surveillance data could support preparedness against autochthonous outbreaks within Europe. Methods: We performed a descriptive analysis of travel-related dengue cases reported by European countries from 2015 through 2019. Using flight passenger data, we calculated travellers’ infection rates (TIR). We investigated the following associations: (i) between TIR and incidence rate in selected countries of infection and (ii) between number of travel-related cases and occurrence of autochthonous outbreaks within Europe. Results: There were 11,478 travel-related dengue cases and the TIR was 2.8 cases per 100,000 travellers. Most cases were infected in Asia (71%), predominantly in south-eastern Asia. The TIR was highest among travellers returning from Asia (6.1/100,000). There was an association between the incidence rate in the country of infection and the TIR but no association between the number of travel-related cases and occurrence of autochthonous outbreaks in Europe. Conclusions: The likelihood of infection in travellers is a function of the ongoing epidemiological situation in the country of exposure. The number of travel-related cases alone is not sufficient to estimate the likelihood of autochthonous outbreaks where vectors are present in Europe. Additional contributing factors such as adequate vectorial capacity and suitable environmental conditions are required.Peer Reviewe

Dengue serosurvey after a 2-month long outbreak in Nîmes, France, 2015: was there more than met the eye?

BackgroundClusters of dengue cases have recently become more frequent in areas of southern France colonised by the vector mosquito Aedes albopictus. In July 2015, a 2-month outbreak of dengue virus serotype 1 (DENV-1) was reported in Nîmes. Aim: We conducted a serosurvey in the affected area at the end of the vector activity period to determine the true extent of dengue transmission. Methods: We collected capillary blood from consenting household members, and information on their medical and travel histories, and exposure to mosquito bites. Recent infections were identified using IgM and IgG anti-DENV ELISA, followed, when positive, by plaque reduction neutralisation tests on serum against DENV 1-4 and West Nile virus. The prevalence estimator was calibrated on reference demographic data. We quantified the spatial clustering of dengue cases within the affected community and inferred the transmission tree. Results: The study participation rate was 39% (564/1,431). Three of 564 participants tested positive for DENV-1 infection (after marginal calibration, 0.41%; 95% confidence interval: 0.00-0.84). The spatial analysis showed that cases were clustered at the household level. Most participants perceived the presence of mosquitos as abundant (83%) and reported frequent mosquito bites (57%). We incidentally identified six past West Nile virus infections (0.9%; 95% CI: 0.2-1.6). Conclusion: This serosurvey confirms the potential for arboviral diseases to cause outbreaks - albeit limited for now - in France and Europe

Campylobacter infections in human : results of threeyears of surveillance 2001 - 2003

The frequency of Campylobacter infections in human, their potential severity, and the existence of preventive measures warrant the creation of a surveillance system. A Campylobacter surveillance system based on private laboratories (PL) was set up in France in 2002 to complement the hospital laboratory-based system(HL). Since 1 January 2001 (for HL), 1 April 2002 (for PL) and 31 December 2003, the Campylobacter National reference Centre analyzed 3 698 strains. Initially thought to be 3.4/100,000, the overall isolation rate was grossly underestimated, as the latest figure is 14/100,000 among children under 5 years old. The strains were mainly C. jejuni (76.9%), followed by C. coli (17.0%) and C. fetus (5.4%). Resistance rates were 41% for ampicillin and 28% for nalidixic acid. Surveillance must be maintained to collect more data on Campylobacter epidemiology in France and to estimate its incidence in the general population.La fréquence des infections humaines à Campylobacter, leur gravité potentielle et l'existence de mesures de prévention justifient une surveillance. En France, un système de surveillance des infections à Campylobacter a été mis en place en avril 2002, à partir des laboratoires de ville (LABM), en complément de celui du réseau des laboratoires hospitaliers (LH) existant depuis 1986. Entre le 1/01/01 (pour les LH), le 1/04/02 (pour les LABM) et le 31/12/03, le Centre National de Référence des Campylobacter a expertisé 3698 souches. Le taux global d'isolement de 3,4/100000 était très largement sous-estimé : il était de 14/100000 pour les enfants âgés de moins S ans. C. jejuni représentait 76,9% des souches, suivi de C. coli (17,0 %) et de C. fetus (5,4%). Le taux de résistance à l'ampicilline était de 41 % et à l'acide nalidixique de 28%. Les efforts pour la surveillance doivent être poursuivis, afin de mieux connaître les caractéristiques épidémiotogiques des infection à Campylobacter en France et de faire des estimations d'incidence en population générale

Comparing the Performance of Three Models Incorporating Weather Data to Forecast Dengue Epidemics in Reunion Island, 2018-2019

We developed mathematical models to analyze a large dengue virus (DENV) epidemic in Reunion Island in 2018-2019. Our models captured major drivers of uncertainty including the complex relationship between climate and DENV transmission, temperature trends, and underreporting. Early assessment correctly concluded that persistence of DENV transmission during the austral winter 2018 was likely and that the second epidemic wave would be larger than the first one. From November 2018, the detection probability was estimated at 10%-20% and, for this range of values, our projections were found to be remarkably accurate. Overall, we estimated that 8% and 18% of the population were infected during the first and second wave, respectively. Out of the 3 models considered, the best-fitting one was calibrated to laboratory entomological data, and accounted for temperature but not precipitation. This study showcases the contribution of modeling to strengthen risk assessments and planning of national and local authorities

Campylobacter Antimicrobial Drug Resistance among Humans, Broiler Chickens, and Pigs, France

We describe isolates from human Campylobacter infection in the French population and the isolates' antimicrobial drug resistance patterns since 1986 and compare the trends with those of isolates from broiler chickens and pigs from 1999 to 2004. Among 5,685 human Campylobacter isolates, 76.2% were C. jejuni, 17.2% C. coli, and 5.0% C. fetus. Resistance to nalidixic acid increased from 8.2% in 1990 to 26.3% in 2004 (p<10-3), and resistance to ampicillin was high over time. Nalidixic acid resistance was greater for C. coli (21.3%) than for C. jejuni (14.9%, p<10-3). C. jejuni resistance to ciprofloxacin in broilers decreased from 31.7% in 2002 to 9.0% in 2004 (p = 0.02). The patterns of resistance to quinolones and fluoroquinolones were similar between 1999 and 2004 in human and broiler isolates for C. jejuni. These results suggest a potential benefit of a regulation policy limiting use of antimicrobial drugs in food animals