Outbreak of trichinellosis related to eating imported wild boar meat, Belgium, 2014.

Trichinellosis is a rare parasitic zoonosis caused by Trichinella following ingestion of raw or undercooked meat containing Trichinella larvae. In the past five years, there has been a sharp decrease in human trichinellosis incidence rates in the European Union due to better practices in rearing domestic animals and control measures in slaughterhouses. In November 2014, a large outbreak of trichinellosis occurred in Belgium, related to the consumption of imported wild boar meat. After a swift local public health response, 16 cases were identified and diagnosed with trichinellosis. Of the 16 cases, six were female. The diagnosis was confirmed by serology or the presence of larvae in the patients' muscle biopsies by histology and/or PCR. The ensuing investigation traced the wild boar meat back to Spain. Several batches of imported wild boar meat were recalled but tested negative. The public health investigation allowed us to identify clustered undiagnosed cases. Early warning alerts and a coordinated response remain indispensable at a European level.

Imputing QALYs from single time point health state descriptions on the EQ-5D and the SF-6D: a comparison of methods for hepatitis a patients.

OBJECTIVES: To explore the impact of applying different non-standardized analytical choices for quality of life measurement to obtain quality-adjusted life years (QALYs). In addition to more widely discussed issues such as the choice of instrument (e.g. EQ-5D or SF-6D?) researchers must also choose between different recall periods, scoring algorithms and interpolations between points of measurement. METHODS: A prospective survey was made among 114 Belgian patients with acute hepatitis A illness. Using non-parametric tests and generalized linear models (GLM's), we compared four different methods to estimate QALY losses, two based on the EQ-5D (administered during the period of illness without recall period) and two based on the SF-6D (administered after illness with 4 weeks recall period). RESULTS: We found statistically significant differences between all methods, with the non-parametric SF-6D-based method yielding the highest median QALY impact (0.032 QALYs). This is more than five times as high as the EQ-5D-based method with linear health improvement, which yields the lowest median QALY impact (0.006 QALYs). CONCLUSIONS: Economic evaluations of health care technologies predominantly use QALYs to quantify health benefits. Non-standardised analytical choices can have a decision-changing impact on cost-effectiveness results, particularly if morbidity takes up a substantial part of the total QALY loss. Yet these choices are rarely subjected to sensitivity analysis. Researchers and decision makers should be aware of the influence of these somewhat arbitrary choices on their results.

Virulence profiling and quantification of verocytotoxin-producing Escherichia coli O145:H28 and O26:H11 isolated during an ice cream-related hemolytic uremic syndrome outbreak.

In September-October 2007, a mixed-serotype outbreak of verocytotoxin-producing Escherichia coli (VTEC) O145:H28 and O26:H11 occurred in the province of Antwerp, Belgium. Five girls aged between 2 and 11 years developed hemolytic uremic syndrome, and seven other coexposed persons with bloody diarrhea were identified. Laboratory confirmation of O145:H28 infection was obtained for three hemolytic uremic syndrome patients, one of whom was coinfected with O26:H11. The epidemiological and laboratory investigations revealed ice cream as the most likely source of the outbreak. The ice cream was produced at a local dairy farm using pasteurized milk. VTEC of both serotypes with indistinguishable pulsed-field gel electrophoresis patterns were isolated from patients, ice cream, and environmental samples. Quantitative analysis of the ice cream indicated concentrations of 2.4 and 0.03 CFU/g for VTEC O145 and O26, respectively. Virulence typing revealed that the repertoire of virulence genes carried by the O145:H28 outbreak strain was comparable to that of O157 VTEC and more exhaustive as compared to the O26:H11 outbreak strain and nonrelated clinical strains belonging to these serotypes. Taken together, these data suggest that O145:H28 played the most important role in this outbreak.

Influenza Vaccination Programs for Healthcare Personnel: Organizational Issues and Beyond.

Healthcare personnel (HCP) are a high priority group for influenza vaccination aiming to protect them but also to protect vulnerable patients and healthcare services from healthcare-associated influenza and HCP absenteeism. Multi-component influenza vaccination programs targeting behavioral, organizational, and administrative barriers are critical, if influenza vaccination rates among HCP are to be raised on a sustained basis. Mandatory influenza vaccination policy is the only single intervention that can achieve high and sustainable vaccination rates in HCP in short term. In this article, we provide an overview of issues pertaining to influenza vaccination of HCP, with an emphasis on organizational issues of influenza vaccination programs.

Cholera among Belgian travellers in Turkey in 2005.

BACKGROUND: Two elderly people among a group of eight Belgian travellers who had stayed in Turkey for 2 weeks, developed a severe enteritis shortly after their return to Belgium. They had travelled by private bus, and had visited different places during their stay in Turkey from 6 to 17 September 2005. METHODS: After notification an epidemiological study was conducted by the Public Health authorities in Antwerp to identify the cause of the infection, to detect other cases, and to trace the source in Turkey. Vibrio cholerae was isolated from stools and a slide agglutination test was performed at the reference laboratory for cholera in Belgium. RESULTS: V. cholerae O1, El Tor, Inaba was identified in the stools of two patients. Four other patients, who suffered from a milder form of the disease, met the case definition of probable cases. No secondary infections among their contacts in Belgium were found. In spite of an epidemiological search conducted by the Turkish Public Health authorities, other cases of cholera in Turkey could not be detected. Nor a source for the outbreak could be established. CONCLUSIONS: The outbreak of imported cholera in Belgium stresses the risk of contracting cholera in a country not considered as a cholera endemic region. It highlights the need for careful laboratory surveillance of intestinal infections in travellers after their return to their homeland. Early detection and prompt reporting are recommended.

Comparison of three Legionella urinary antigen assays during an outbreak of legionellosis in Belgium.

During an outbreak of legionellosis in Belgium, urine samples of 32 legionellosis patients were tested with three Legionella urinary antigen assays: the Biotest enzyme immunoassay (EIA) kit, the Binax EIA kit and the Binax NOW Immunochromatographic Test kit. The three tests were concomitantly compared. The test sensitivities on the first urine samples were 65.6 % for the Biotest EIA, 50.0 % for the Binax EIA and 56.3 % for the Binax NOW. Testing of a second urine sample increased the sensitivities to 71.9 %, 59.4 % and 65.6 %, respectively. The differences were not statistically significant. In outbreak settings, testing second samples from patients presenting with symptoms but initially testing negative and/or concentrating urine samples for testing might be valuable additions to the urinary antigen test to increase the sensitivities of the tests.

Cost-effectiveness of hepatitis A vaccination for adults in Belgium.

Hepatitis A vaccination targeting adults (or adult risk-groups like e.g. travellers, health care workers, soldiers or teachers) could be considered an alternative to a universal infant or adolescent vaccination program in low endemic countries. We estimated the current disease burden of hepatitis A in Belgium, and evaluated whether adult vaccination is cost-effective. We used a Markov cohort model to simulate the costs and effects of (1) vaccination of adults and (2) serological screening of adults and vaccination of susceptibles and compared these with the current situation. The results indicated that these expanded vaccination strategies are not cost-effective in the epidemiological circumstances of a typical low-endemic western country. In order to gain 1 quality-adjusted life year the health care payer would have to pay 185,000€ for vaccination and 223,000€ for screening and vaccination of seronegatives. For adult vaccination to be cost-effective, risk-groups would need to be exposed to a force of infection that is 3.5-4 times higher than currently estimated in the general population; or the total costs of vaccination would have to drop with approximately 75%.

An outbreak of hepatitis A associated with the consumption of raw beef.

BACKGROUND: In July 2004, a sharp increase of hepatitis A, a notifiable disease in Belgium, was detected. OBJECTIVES: We investigated the outbreak in order to identify the source and take appropriate action. STUDY DESIGN: We conducted an outbreak investigation which included a matched case-control study to analyse the association with a range of food items and food providers. A phylogenetic analysis was used to study the relation between the outbreak cases and the identified source. RESULTS: We registered 269 cases of hepatitis A. Consumption of raw beef (OR 16.0; 95% CI 2.1-120.7) was the most probable way of infection. A food handler working at an epidemiologically linked meat distribution plant had contracted hepatitis A 1 month before the start of the outbreak. HAV strains from the food handler and the patients involved in the outbreak were monophyletically related. CONCLUSIONS: Since serological immunity in Belgium is decreasing over time, foodborne outbreaks of hepatitis A are a substantial risk. In this outbreak, a single food handler, at the level of the distribution chain, has been identified as the most likely source, through cross-contamination of raw beef. This outbreak investigation suggests the need to consider vaccination against hepatitis A in food handlers.

An outbreak of serogroup C meningococcal disease in the province of Antwerp (Belgium) in 2001-2002.

In 2001 an outbreak of Neisseria menigitidis serogroup C occurred in the province of Antwerp (Belgium). Over a year the incidence rate of meningococcal disease (MD) increased from 3.9 per 100,000 to 9.1 per 100,000 with a shift from serogroup B (87%) in 2000 to serogroup C (66%) in 2001. The most prominent phenotype was C:2a:P1.2,5. The incidence rate for serogroup C MD increased from 0.4 per 100,000 to 4.5 per 100,000 in 2001. The case fatality rate was 6.7% in 2001. After the introduction of a mass vaccination campaign with a conjugated vaccine against serogroup C MD the incidence of serogroup C MD fell from 4.5 to 1.8 per 100,000. As a result of the analysis of this outbreak, it was proposed to offer a vaccine against serogroup C to all people under 19 years of age. Part of this plan has been implemented to date in Belgium.