Climate change projections of West Nile virus infections in Europe: implications for blood safety practices

Background: West Nile virus (WNV) is transmitted by mosquitoes in both urban as well as in rural environments and can be pathogenic in birds, horses and humans. Extrinsic factors such as temperature and land use are determinants of WNV outbreaks in Europe, along with intrinsic factors of the vector and virus. Methods: With a multivariate model for WNV transmission we computed the probability of WNV infection in 2014, with July 2014 temperature anomalies. We applied the July temperature anomalies under the balanced A1B climate change scenario (mix of all energy sources, fossil and non-fossil) for 2025 and 2050 to model and project the risk of WNV infection in the future. Since asymptomatic infections are common in humans (which can result in the contamination of the donated blood) we estimated the predictive prevalence of WNV infections in the blood donor population. Results: External validation of the probability model with 2014 cases indicated good prediction, based on an Area Under Curve (AUC) of 0.871 (SD = 0.032), on the Receiver Operating Characteristic Curve (ROC). The climate change projections for 2025 reveal a higher probability of WNV infection particularly at the edges of the current transmission areas (for example in Eastern Croatia, Northeastern and Northwestern Turkey) and an even further expansion in 2050. The prevalence of infection in (blood donor) populations in the outbreak-affected districts is expected to expand in the future. Conclusions Predictive modelling of environmental and climatic drivers of WNV can be a valuable tool for public health practice. It can help delineate districts at risk for future transmission. These areas can be subjected to integrated disease and vector surveillance, outreach to the public and health care providers, implementation of personal protective measures, screening of blood donors, and vector abatement activities. (Résumé d'auteur

The impact of economic crises on communicable disease transmission and control: a systematic review of the evidence.

There is concern among public health professionals that the current economic downturn, initiated by the financial crisis that started in 2007, could precipitate the transmission of infectious diseases while also limiting capacity for control. Although studies have reviewed the potential effects of economic downturns on overall health, to our knowledge such an analysis has yet to be done focusing on infectious diseases. We performed a systematic literature review of studies examining changes in infectious disease burden subsequent to periods of crisis. The review identified 230 studies of which 37 met our inclusion criteria. Of these, 30 found evidence of worse infectious disease outcomes during recession, often resulting from higher rates of infectious contact under poorer living circumstances, worsened access to therapy, or poorer retention in treatment. The remaining studies found either reductions in infectious disease or no significant effect. Using the paradigm of the "SIR" (susceptible-infected-recovered) model of infectious disease transmission, we examined the implications of these findings for infectious disease transmission and control. Key susceptible groups include infants and the elderly. We identified certain high-risk groups, including migrants, homeless persons, and prison populations, as particularly vulnerable conduits of epidemics during situations of economic duress. We also observed that the long-term impacts of crises on infectious disease are not inevitable: considerable evidence suggests that the magnitude of effect depends critically on budgetary responses by governments. Like other emergencies and natural disasters, preparedness for financial crises should include consideration of consequences for communicable disease control

Tracking infectious diseases in a warming world.

Using infectious diseases sensitive to climate as indicators of climate change helps stimulate andinform public health response

School life expectancy and risk for tuberculosis in Europe.

OBJECTIVE: This study aims to investigate the effect of country-level school life expectancy on Tuberculosis (TB) incidence to gain further understanding of substantial variation in TB incidence across Europe. METHODS: An ecological study examined the prospective association between baseline country-level education in 2000 measured by school life expectancy and TB incidence in 2000-2010 in 40 countries of the WHO European region using quantile regression. Subsequently, to validate the ecological associations between education and TB incidence, an individual-level analysis was performed using case-based data in 29 EU/EEA countries from the European Surveillance System (TESSy) and simulating a theoretical control group. RESULTS: The ecological analysis showed that baseline school life expectancy had a negative prospective association with TB incidence. We observed consistent negative effects of school life expectancy on individuals' TB infections prospectively. CONCLUSIONS: These findings suggests that country-level education is an important determinant of individual-level TB infection in the region, and in the absence of a social determinants indicator that is routinely collected for reportable infectious diseases, the adoption of country-level education for reportable infectious diseases would significantly advance the field

Mapping Climate Change Vulnerabilities to Infectious Diseases in Europe

Background: The incidence, outbreak frequency, and distribution of many infectious diseases are generally expected to change as a consequence of climate change, yet there is limited regional information available to guide decision making