The optimisation of Salmonella surveillance programmes for pullet and layer farms using local farm density as a risk factor.

Human salmonellosis cases are often caused by Salmonella serovars Enteritidis and Typhimurium and associated with the consumption of eggs and egg products. Many countries therefore implemented general surveillance programmes on pullet and layer farms. The identification of risk factors for Salmonella infection may be used to improve the performance of these surveillance programmes.

Estimating the introduction time of highly pathogenic avian influenza into poultry flocks.

The estimation of farm-specific time windows for the introduction of highly-pathogenic avian influenza (HPAI) virus can be used to increase the efficiency of disease control measures such as contact tracing and may help to identify risk factors for virus introduction. The aims of this research are to (1) develop and test an accurate approach for estimating farm-specific virus introduction windows and (2) evaluate this approach by applying it to 11 outbreaks of HPAI (H5N8) on Dutch commercial poultry farms during the years 2014 and 2016. We used a stochastic simulation model with susceptible, infectious and recovered/removed disease stages to generate distributions for the period from virus introduction to detection.

Burden of varicella complications in secondary care, England, 2004 to 2017.

BackgroundStrategies to control varicella vary across Europe. Evidence from established programmes has prompted the United Kingdom to re-evaluate the need for universal vaccination. The burden of complicated varicella is a key parameter in the cost-effectiveness analysis.

Impact and Cost-effectiveness of Selective Human Papillomavirus Vaccination of Men Who Have Sex With Men.

Background: Men who have sex with men (MSM) have a high lifetime risk of anogenital warts and cancers related to infection with human papillomavirus (HPV). They also benefit less from herd protection than heterosexual males in settings with female-only HPV vaccination.

Methods: We evaluated the potential health impact and cost-effectiveness of offering vaccination to MSM who visit genitourinary medicine (GUM) clinics.

The burden of hospitalisation for varicella and herpes zoster in England from 2004 to 2013.

Objectives: We aimed to determine the hospital burden of varicella-zoster virus infection (VZV) in England during 2004-2013 to support a future cost-effectiveness analysis of a childhood varicella vaccination programme.

Methods: We analysed the incidence, duration, outcome and costs of hospitalisations for VZV using the Hospital Episode Statistics (HES) database for the general and immunocompetent population. Mortality in HES was validated using data from the Office for National Statistics (ONS).

Mixtures as a fungicide resistance management tactic.

We have reviewed the experimental and modeling evidence on the use of mixtures of fungicides of differing modes of action as a resistance management tactic. The evidence supports the following conclusions. 1.

The emergence of resistance to fungicides.

Many studies exist about the selection phase of fungicide resistance evolution, where a resistant strain is present in a pathogen population and is differentially selected for by the application of fungicides. The emergence phase of the evolution of fungicide resistance--where the resistant strain is not present in the population and has to arise through mutation and subsequently invade the population--has not been studied to date. Here, we derive a model which describes the emergence of resistance in pathogen populations of crops.

Modeling future conservation of Hawaiian honeycreepers by mosquito management and translocation of disease-tolerant Amakihi.

Avian malaria is an important cause of the decline of endemic Hawaiian honeycreepers. Because of the complexity of this disease system we used a computer model of avian malaria in forest birds to evaluate how two proposed conservation strategies: 1) reduction of habitat for mosquito larvae and 2) establishment of a low-elevation, malaria-tolerant honeycreeper (Hawaii Amakihi) to mid-elevation forests would affect native Hawaiian honeycreeper populations. We evaluated these approaches in mid-elevation forests, where malaria transmission is seasonal and control strategies are more likely to work.

Do high levels of diffuse and chronic metal pollution in sediments of Rhine and Meuse floodplains affect structure and functioning of terrestrial ecosystems?

This paper (re)considers the question if chronic and diffuse heavy metal pollution (cadmium, copper, lead and zinc) affects the structure and functioning of terrestrial ecosystems of Biesbosch National Park, the floodplain area of rivers Meuse and Rhine. To reach this aim, we integrated the results of three projects on: 1. the origin, transfer and effects of heavy metals in a soil-plant-snail food chain; 2.

Metal accumulation in the earthworm Lumbricus rubellus. Model predictions compared to field data.

The mechanistic bioaccumulation model OMEGA (Optimal Modeling for Ecotoxicological Applications) is used to estimate accumulation of zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) in the earthworm Lumbricus rubellus. Our validation to field accumulation data shows that the model accurately predicts internal cadmium concentrations. In addition, our results show that internal metal concentrations in the earthworm are less than linearly (slope<1) related to the total concentration in soil, while risk assessment procedures often assume the biota-soil accumulation factor (BSAF) to be constant.