Infection risks of city canal swimming events in the Netherlands in 2016.

INTRODUCTION: Swimming events in city canals are gaining popularity in the Netherlands, even though canal water is usually not officially designated for recreational use. Knowledge regarding the risk of infection after swimming in canals is limited. An outbreak was reported in 2015 following a canal swimming event in Utrecht, the Netherlands. Local governments were concerned about the health risks of such events. In order to assess the safety of canal swimming, the Public Health Service (PHS) prospectively investigated two city canal swimming events in 2015. In 2016, we repeated this study, aiming to prospectively determine the risks of infection during two urban swimming events, the Utrecht SingelSwim 2016 (USS) and the Amsterdam City Swim 2016 (ACS). METHODS: We sent online questionnaires to 271 USS participants and 2697 ACS participants, concerning personal characteristics, symptoms, and exposure. Participants were asked to forward the questionnaire to three relatives, i.e., non-exposed. We analyzed water samples from the USS venue taken during the event, as well as stool samples of USS participants with acute gastrointestinal illness (AGI). AGI was defined as diarrhea and/or vomiting within seven days after the event. We calculated adjusted risk ratios (RR) for AGI in the exposed group compared with non-exposed respondents, using binomial regression models. RESULTS: The questionnaire was returned by 160 USS participants (exposed) (59%) and 40 non-exposed relatives. Five percent of the exposed (n = 17) and 3% of non-exposed (n = 1) reported AGI (RR = 1.69; 95% CI: 0.23-12.46). Norovirus genogroup II was detected in two of six USS water samples and in none of the three stool samples. In one of three stool samples, rotavirus was detected. The questionnaire was returned by 1169 ACS participants (exposed) (43%) and 410 non-exposed relatives. Six percent of the exposed (n = 71) and 1% of non-exposed (n = 5) reported AGI (RR 4.86; 95% CI: 1.98-11.97). CONCLUSION: Results of the ACS event showed a higher risk for AGI among the exposed, indicating that participants of events in urban canals in the Netherlands could be at a higher risk for AGI than those not participating. The inconclusive results from the USS are likely due to the small sample size. Swimming in non-monitored open water can bring health risks and more knowledge about environmental and human risk factors helps reduce the risk by being able to more specifically advise organizations and governments.

Targeted outreach hepatitis B vaccination program in high-risk adults: The fundamental challenge of the last mile.

BACKGROUND: The aim of this study was to evaluate the cost-effectiveness of the on-going decentralised targeted hepatitis B vaccination program for behavioural high-risk groups operated by regional public health services in the Netherlands since 1-November-2002. Target groups for free vaccination are men having sex with men (MSM), commercial sex workers (CSW) and hard drug users (HDU). Heterosexuals with a high partner change rate (HRP) were included until 1-November-2007. METHODS: Based on participant, vaccination and serology data collected up to 31-December-2012, the number of participants and program costs were estimated. Observed anti-HBc prevalence was used to estimate the probability of susceptible individuals per risk-group to become infected with hepatitis B virus (HBV) in their remaining life. We distinguished two time-periods: 2002-2006 and 2007-2012, representing different recruitment strategies and target groups. Correcting for observed vaccination compliance, the number of future HBV-infections avoided was estimated per risk-group. By combining these numbers with estimates of life-years lost, quality-of-life losses and healthcare costs of HBV-infections - as obtained from a Markov model-, the benefit of the program was estimated for each risk-group separately. RESULTS: The overall incremental cost-effectiveness ratio of the program was €30,400/QALY gained, with effects and costs discounted at 1.5% and 4%, respectively. The program was more cost-effective in the first period (€24,200/QALY) than in the second period (€42,400/QALY). In particular, the cost-effectiveness for MSM decreased from €20,700/QALY to €47,700/QALY. DISCUSSION AND CONCLUSION: This decentralised targeted HBV-vaccination program is a cost-effective intervention in certain unvaccinated high-risk adults. Saturation within the risk-groups, participation of individuals with less risky behaviour, and increased recruitment investments in the second period made the program less cost-effective over time. The project should therefore discus how to reduce costs per risk-group, increase effects or when to integrate the vaccination in regular healthcare.

Validation of the Mental Alternation Test with the Mini-Mental State Examination in geriatric psychiatric inpatients and normal controls.

The Mental Alternation Test (MAT) is a bedside test of cognition that was used for the detection of human immunodeficiency virus (HIV)-related cognitive impairment. It has been shown to have good reproducibility and inter-rater reliability, and takes only 60 seconds to administer. To assess the utility of the MAT in the geriatric primary care and geriatric psychiatric settings, we used the Mini-Mental State Examination (MMSE) as a further validation of the test. This cohort study included 20 geriatric psychiatric inpatients, 15 normal geriatric controls, and four normal adult controls. The study was conducted within the inpatient psychiatric unit of a referral hospital. Scores on the MAT and the MMSE were compared using correlation calculations. Test score means and standard deviations were computed for each study population. Test score cutoffs derived from a previous study were used to determine the sensitivity and specificity of the MAT as compared with the MMSE. The MAT score was found to correlate significantly with the MMSE score (r =.84, P <.0001). Scores on the MAT were predictive of scores on the MMSE, with a sensitivity of 91% and a specificity of 100%. We conclude that MAT is a good test of cognition in both geriatric primary care and geriatric psychiatric populations. It has both good specificity and sensitivity, and its ease of administration and inter-rater reliability make it a useful diagnostic tool for identifying those patients who may need further cognitive evaluations.

Neurotoxicity associated with suspected southern Pacific rattlesnake (Crotalus viridis helleri) envenomation.

An 18-year-old man was bitten on the hand by a snake he believed to be a Southern Pacific rattlesnake (Crotalus viridis helleri). Within minutes he developed generalized weakness, difficulty breathing, diplopia, dysphagia, and dysphonia. Neurological examination revealed ptosis and decreased motor strength. These symptoms partially improved after administration of Antivenin (Crotalidae) Polyvalent, but the patient continued to have difficulty walking for several days due to weakness. In addition to neurological symptoms, the patient also experienced pain immediately after the bite occurred and rapid swelling of the entire extremity, which extended beyond the shoulder. He complained of a metallic taste in his mouth and developed intense muscle fasciculations of the face, tongue, and upper extremities, which lasted for 2 days and did not improve with antivenin treatment. He exhibited laboratory evidence of coagulopathy and rhabdomyolysis. Although neurotoxins are known to occur in the venom of certain populations of rattlesnakes, only a few clinical reports describing severe neurological symptoms appear in the literature. To our knowledge, this is the first reported case of neurotoxicity associated with a suspected Southern Pacific rattlesnake envenomation.