Current and future Burden of Communicable Diseases in the European Union and EEA/EFTA countries (BCoDE). Methodology protocol

Mangen M-J, Gibbons C, Kretzschmar M, et al. Current and future Burden of Communicable Diseases in the European Union and EEA/EFTA countries (BCoDE). Methodology protocol. ECDC Technical Report. Stockholm: ECDC; 2011

Current and future Burden of Communicable Diseases in the European Union and EEA/EFTA countries (BCoDE). Methodology protocol

Mangen M-J, Gibbons C, Kretzschmar M, et al. Current and future Burden of Communicable Diseases in the European Union and EEA/EFTA countries (BCoDE). Methodology protocol. ECDC Technical Report. Stockholm: ECDC; 2011

Inactivation of Caliciviruses

The viruses most commonly associated with food- and waterborne outbreaks of gastroenteritis are the noroviruses. The lack of a culture method for noroviruses warrants the use of cultivable model viruses to gain more insight on their transmission routes and inactivation methods. We studied the inactivation of the reported enteric canine calicivirus no. 48 (CaCV) and the respiratory feline calicivirus F9 (FeCV) and correlated inactivation to reduction in PCR units of FeCV, CaCV, and a norovirus. Inactivation of suspended viruses was temperature and time dependent in the range from 0 to 100°C. UV-B radiation from 0 to 150 mJ/cm(2) caused dose-dependent inactivation, with a 3 D (D = 1 log(10)) reduction in infectivity at 34 mJ/cm(2) for both viruses. Inactivation by 70% ethanol was inefficient, with only 3 D reduction after 30 min. Sodium hypochlorite solutions were only effective at >300 ppm. FeCV showed a higher stability at pH <3 and pH >7 than CaCV. For all treatments, detection of viral RNA underestimated the reduction in viral infectivity. Norovirus was never more sensitive than the animal caliciviruses and profoundly more resistant to low and high pH. Overall, both animal viruses showed similar inactivation profiles when exposed to heat or UV-B radiation or when incubated in ethanol or hypochlorite. The low stability of CaCV at low pH suggests that this is not a typical enteric (calici-) virus. The incomplete inactivation by ethanol and the high hypochlorite concentration needed for sufficient virus inactivation point to a concern for decontamination of fomites and surfaces contaminated with noroviruses and virus-safe water

ECDC Round Table Report and ProMed-mail most useful international information sources for the Netherlands Early Warning Committee.

The Netherlands Early Warning Committee (NEWC) aims to identify infectious diseases causing a potential threat to Dutch public health. Threats are assessed and published as (information) alerts for public health experts. To identify threats from abroad, the NEWC screens 10 sources reporting disease outbreaks each week. To identify the sources essential for complete and timely reporting, we retrospectively analysed 178 international alerts published between 31 January 2013 and 30 January 2014. In addition, we asked the four NEWC coordinators about the required time to scan the information sources. We documented the date and source in which the signal was detected. The ECDC Round Table (RT) Report and ProMED-mail were the most complete and timely sources, reporting 140 of 178 (79%) and 121 of 178 (68%) threats respectively. The combination of both sources reported 169 (95%) of all threats in a timely manner. Adding any of the other sources resulted in minor increases in the total threats found, but considerable additional time investment per additional threat. Only three potential relevant threats (2%) would have been missed by only using the ECDC RT Report and ProMed-mail. We concluded that using only the ECDC RT Report and ProMed-mail to identify threats from abroad maintains a sensitive Early Warning System

Fluvio-marine sediment partitioning as a function of basin depth

Progradational fluvio-deltaic systems tend towards but cannot reach equilibrium, a state in which the longitudinal profile does not change shape and all sediment is bypassed beyond the shoreline. They cannot reach equilibrium because progradation of the shoreline requires aggradation along the longitudinal profile. Therefore progradation provides a negative feedback, unless relative sea level falls at a sufficient rate to cause non-aggradational extension of the longitudinal profile. How closely fluvio-deltaic systems approach equilibrium is dependent on their progradation rate, which is controlled by water depth and downstream allogenic controls, and governs sediment partitioning between the fluvial, deltaic, and marine domains. Here, six analogue models of coastal fluvio-deltaic systems and small prograding shelf margins are examined to better understand the effect of water depth, subsidence, and relative sea-level variations upon longitudinal patterns of sediment partitioning and grain-size distribution that eventually determine large-scale stratigraphic architecture. Fluvio-deltaic systems prograding in relatively deep-water environments are characterized by relatively low progradation rates compared to shallow-water systems. This allows these deeper water systems to approach equilibrium more closely, enabling them to construct less concave and steeper longitudinal profiles that provide low accommodation to fluvial systems. Glacio-eustatic sea-level variations and subsidence modulate the effects of water depth on the longitudinal profile. Systems are closest to equilibrium during falling relative sea level and early lowstand, resulting in efficient sediment transport towards the shoreline at those times. Additionally, the strength of the response to relative sea-level fall differs depending on water depth. In systems prograding into deep water, relative sea-level fall causes higher sediment bypass rates and generates significantly stronger erosion than in shallow-water systems, which increases the probability of incised-valley formation. Water depth in the receiving basin thus forms a first-order control on the sediment partitioning along the longitudinal profile of fluvio-deltaic systems and the shelf clinoform style. It also forms a control on the availability of sand-grade sediment at the shoreline that can potentially be remobilized and redistributed into deeper marine environments. Key findings are subsequently applied to the literature of selected shelf clinoform successions

The economic burden of a Salmonella Thompson outbreak caused by smoked salmon in the Netherlands, 2012-2013

BACKGROUND: In 2012, the Netherlands experienced the most extensive food-related outbreak of Salmonella ever recorded. It was caused by smoked salmon contaminated with Salmonella Thompson during processing. In total, 1149 cases of salmonellosis were laboratory confirmed and reported to RIVM. Twenty percent of cases was hospitalised and four cases were reported to be fatal. The purpose of this study was to estimate total costs of the Salmonella Thompson outbreak. METHODS: Data from a case-control study were used to estimate the cost-of-illness of reported cases (i.e. healthcare costs, patient costs and production losses). Outbreak control costs were estimated based on interviews with staff from health authorities. Using the Dutch foodborne disease burden and cost-of-illness model, we estimated the number of underestimated cases and the associated cost-of-illness. RESULTS: The estimated number of cases, including reported and underestimated cases was 21 123. Adjusted for underestimation, the total cost-of-illness would be €6.8 million (95% CI €2.5-€16.7 million) with productivity losses being the main cost driver. Adding outbreak control costs, the total outbreak costs are estimated at €7.5 million. CONCLUSION: In the Netherlands, measures are taken to reduce salmonella concentrations in food, but detection of contamination during food processing remains difficult. As shown, Salmonella outbreaks have the potential for a relatively high disease and economic burden for society. Early warning and close cooperation between the industry, health authorities and laboratories is essential for rapid detection, control of outbreaks, and to reduce disease and economic burden

Calicivirus Inactivation by Nonionizing (253.7-Nanometer-Wavelength [UV]) and Ionizing (Gamma) Radiation

Noroviruses (previously Norwalk-like viruses) are the most common viral agents associated with food- and waterborne outbreaks of gastroenteritis. In the absence of culture methods for noroviruses, animal caliciviruses were used as model viruses to study inactivation by nonionizing (253.7-nm-wavelength [UV]) and ionizing (gamma) radiation. Here, we studied the respiratory feline calicivirus (FeCV) and the presumed enteric canine calicivirus (CaCV) and compared them with the well-studied bacteriophage MS2. When UV irradiation was used, a 3-log(10) reduction was observed at a fluence of 120 J/m(2) in the FeCV suspension and at a fluence of 200 J/m(2) for CaCV; for the more resistant phage MS2 there was a 3-log(10) reduction at a fluence of 650 J/m(2). Few or no differences were observed between levels of UV inactivation in high- and low-protein-content virus stocks. In contrast, ionizing radiation could readily inactivate MS2 in water, and there was a 3-log(10) reduction at a dose of 100 Gy, although this did not occur when the phage was diluted in high-protein-content stocks of CaCV or FeCV. The low-protein-content stocks showed 3-log(10) reductions at a dose of 500 Gy for FeCV and at a dose of 300 for CaCV. The inactivation rates for both caliciviruses with ionizing and nonionizing radiation were comparable but different from the inactivation rates for MS2. Although most FeCV and CaCV characteristics, such as overall particle and genome size and structure, are similar, the capsid sequences differ significantly, making it difficult to predict human norovirus inactivation. Adequate management of UV and gamma radiation processes for virus inactivation should limit public health risks

To notify or not to notify : Decision aid for policy makers on whether to make an infectious disease mandatorily notifiable

Mandatory notification can be a useful tool to support infectious disease prevention and control. Guidelines are needed to help policymakers decide whether mandatory notification of an infectious disease is appropriate. We developed a decision aid, based on a range of criteria previously used in the Netherlands or in other regions to help decide whether to make a disease notifiable. Criteria were categorised as being effective, feasible and necessary with regard to the relevance of mandatory notification. Expert panels piloted the decision aid. Here we illustrate its use for three diseases (Vibrio vulnificus infection, chronic Q fever and dengue fever) for which mandatory notification was requested. For dengue fever, the expert panel advised mandatory notification; for V. vulnificus infection and chronic Q fever, the expert panel concluded that mandatory notification was not (yet) justified. Use of the decision aid led to a structured, transparent decision making process and a thorough assessment of the advantages and disadvantages of mandatory notification of these diseases. It also helped identify knowledge gaps that required further research before a decision could be made. We therefore recommend use of this aid for public health policy making

To notify or not to notify : Decision aid for policy makers on whether to make an infectious disease mandatorily notifiable

Mandatory notification can be a useful tool to support infectious disease prevention and control. Guidelines are needed to help policymakers decide whether mandatory notification of an infectious disease is appropriate. We developed a decision aid, based on a range of criteria previously used in the Netherlands or in other regions to help decide whether to make a disease notifiable. Criteria were categorised as being effective, feasible and necessary with regard to the relevance of mandatory notification. Expert panels piloted the decision aid. Here we illustrate its use for three diseases (Vibrio vulnificus infection, chronic Q fever and dengue fever) for which mandatory notification was requested. For dengue fever, the expert panel advised mandatory notification; for V. vulnificus infection and chronic Q fever, the expert panel concluded that mandatory notification was not (yet) justified. Use of the decision aid led to a structured, transparent decision making process and a thorough assessment of the advantages and disadvantages of mandatory notification of these diseases. It also helped identify knowledge gaps that required further research before a decision could be made. We therefore recommend use of this aid for public health policy making