ABSTRACT
We describe the outbreak investigation associated with an unusual increase in Salmonella Goldcoast cases in Hungary observed in autumn 2009, which included descriptive and analytical epidemiological studies and microbiological and veterinary investigations. Sixty cases were identified between 1 January 2009 and 1 March 2010, 50 of them from late July 2009 to January 2010. Of 50 S. Goldcoast isolates, 44 showed an indistinguishable pulsed-field gel electrophoresis profile. We conducted a matched case-control study that indicated a statistically significant association between S. Goldcoast infection and the consumption of pork cheese. The majority of cases (seven of nine) reporting consumption of this product belonged to a single family cluster. After removing six cases of this cluster, pork cheese still showed an elevated but non-significant risk for being a case in the univariable analysis (Mantel-Haenszel odds ratio (MH OR): 3.87, 95% confidence interval (CI): 0.38-39.47). A single S. Goldcoast isolate was identified during routine veterinary surveillance activities in 2009 in minced beef from a butcher's shop, originating from an abattoir where also pigs were slaughtered. We conclude that the outbreak was probably due to multiple sources of contaminated meat, probably pork, released on the market over a period of several months in 2009.
Subject(s)
Foodborne Diseases/epidemiology , Health Knowledge, Attitudes, Practice , Salmonella Food Poisoning/epidemiology , Case-Control Studies , Cheese/microbiology , Disease Notification , Disease Outbreaks , Food Microbiology/standards , Foodborne Diseases/microbiology , Humans , Hungary/epidemiology , Meat Products/microbiology , Population Surveillance , Salmonella/classification , Salmonella/isolation & purification , Salmonella Food Poisoning/microbiology , Socioeconomic Factors , Surveys and Questionnaires , Vomiting/complicationsABSTRACT
Within the Influenza Monitoring Vaccine Effectiveness in Europe (I-MOVE) project we conducted a multicentre casecontrol study in eight European Union (EU) Member States to estimate the 2011/12 influenza vaccine effectiveness against medically attended influenza-like illness (ILI) laboratory-confirmed as influenza A(H3) among the vaccination target groups. Practitioners systematically selected ILI / acute respiratory infection patients to swab within seven days of symptom onset. We restricted the study population to those meeting the EU ILI case definition and compared influenza A(H3) positive to influenza laboratory-negative patients. We used logistic regression with study site as fixed effect and calculated adjusted influenza vaccine effectiveness (IVE), controlling for potential confounders (age group, sex, month of symptom onset, chronic diseases and related hospitalisations, number of practitioner visits in the previous year). Adjusted IVE was 25% (95% confidence intervals (CI): -6 to 47) among all ages (n=1,014), 63% (95% CI: 26 to 82) in adults aged between 15 and 59 years and 15% (95% CI: -33 to 46) among those aged 60 years and above. Adjusted IVE was 38% (95%CI: -8 to 65) in the early influenza season (up to week 6 of 2012) and -1% (95% CI: -60 to 37) in the late phase. The results suggested a low adjusted IVE in 2011/12. The lower IVE in the late season could be due to virus changes through the season or waning immunity. Virological surveillance should be enhanced to quantify change over time and understand its relation with duration of immunological protection. Seasonal influenza vaccines should be improved to achieve acceptable levels of protection.