The 2024 Europe report of the Lancet Countdown on health and climate change: unprecedented warming demands unprecedented action

A climatic suitability indicator to support Leishmania infantum surveillance in Europe: a modelling study

Background

Leishmaniases are neglected diseases transmitted by sand flies. They disproportionately affect vulnerable groups globally. Understanding the relationship between climate and disease transmission allows the development of relevant decision-support tools for public health policy and surveillance. The aim of this modelling study was to develop an indicator that tracks climatic suitability for Leishmania infantum transmission in Europe at the subnational level.

Methods

Historical records of sand fly vectors, human leishmaniasis, bioclimatic indicators, and environmental variables were integrated in a machine learning framework (XGBoost) to predict suitability in two past periods (2001-2010 and 2011-2020). We further assessed if predictions were associated with human and animal disease data from selected countries (France, Greece, Italy, Portugal, and Spain).

Findings

An increase in the number of climatically suitable regions for leishmaniasis was detected, especially in southern and eastern countries, coupled with a northward expansion towards central Europe. The final model had excellent predictive ability (AUC = 0.970 [0.947-0.993]), and the suitability predictions were positively associated with human leishmaniasis incidence and canine seroprevalence for Leishmania.

Interpretation

This study demonstrates how key epidemiological data can be combined with open-source climatic and environmental information to develop an indicator that effectively tracks spatiotemporal changes in climatic suitability and disease risk. The positive association between the model predictions and human disease incidence demonstrates that this indicator could help target leishmaniasis surveillance to transmission hotspots.

Funding

European Union Horizon Europe Research and Innovation Programme (European Climate-Health Cluster), United Kingdom Research and Innovation.

A Review of the Increasing Global Impact of Climate Change on Human Health and Approaches to Medical Preparedness

At the end of 2023, the World Health Organization (WHO) identified climate change as the greatest threat to human health. Global climate change is due to rising atmospheric concentrations of greenhouse gasses, primarily due to the burning of fossil fuels, mainly by populations in developed and developing countries. In 2022, the world experienced the highest temperatures for over 100,000 years. However, in 2022, global investment in fossil fuels increased by 10% and reached more than USD 1 trillion. The 2023 Lancet Commission report concluded that there has been little progress in protecting individuals from the adverse health effects of climate change. It is clear that global action against climate change needs to move more quickly, and the inequalities in the effects of climate change, including the impact on health, are increasing. This article aims to review the ongoing global impact of climate change on human health at individual and population levels, including recent initiatives and medical approaches to prepare for this increasing challenge.

Perspectives on climate action and the changing burden of infectious diseases among young Italian doctors and students: a national survey

Background

The eco-climatic crisis has been defined by the World Health Organization as the "single biggest health threat facing humanity," influencing both the emergence of zoonoses and the spread of vector-borne and water-borne diseases. The aim of this survey was to explore knowledge, eco-anxiety and attitudes toward the ecological and climate crisis among young Italian doctors and medical students.

Methods

A cross-sectional, multicenter survey was conducted from November 2022 to June 2023, by administering an anonymous questionnaire to Italian doctors and students of medicine. Endpoint of the study was a Knowledge, Attitudes and Practices (KAP) score on ecological and climate crisis (0-20 points). Association between variables and KAP score was assessed by Kruskal-Wallis' or Spearman's test, as appropriate, and significant variables were included into ordinal regression model and reported as adjusted odds ratio (aOR) with their 95% confidence intervals (CI).

Results

Both KAP and eco-anxiety scores showed acceptable levels of consistency with Cronbach's alpha. A total of 605 medical doctors and students living in 19 Italian regions were included in the study. Median age [Q1-Q3] was 27.6 [24.1-31.3] and females were 352 (58.2%). Despite showing good attitudes toward climate action, knowledge gap were found, with 42.5% (n = 257) of the respondents not knowing the temperature limits set by the Paris Agreements and 45.5% (n = 275) believing that climate change is caused by sunspots. Fears suggestive for eco-anxiety were common. At multivariable ordinal regression, high levels of eco-anxiety (aOR 1.29, p = 0.001) and low trust in government action (aOR 1.96, p = 0.003) were associated with a higher KAP score. Only one Italian medical school offered an educational module on climate change.

Conclusion

Young Italian doctors and medical students are concerned about the climate crisis but show poor knowledge of these topics. The Italian academic system should urgently respond to this need.

Public health aspects of Vibrio spp. related to the consumption of seafood in the EU

Vibrio parahaemolyticus, Vibrio vulnificus and non-O1/non-O139 Vibrio cholerae are the Vibrio spp. of highest relevance for public health in the EU through seafood consumption. Infection with V. parahaemolyticus is associated with the haemolysins thermostable direct haemolysin (TDH) and TDH-related haemolysin (TRH) and mainly leads to acute gastroenteritis. V. vulnificus infections can lead to sepsis and death in susceptible individuals. V. cholerae non-O1/non-O139 can cause mild gastroenteritis or lead to severe infections, including sepsis, in susceptible individuals. The pooled prevalence estimate in seafood is 19.6% (95% CI 13.7-27.4), 6.1% (95% CI 3.0-11.8) and 4.1% (95% CI 2.4-6.9) for V. parahaemolyticus, V. vulnificus and non-choleragenic V. cholerae, respectively. Approximately one out of five V. parahaemolyticus-positive samples contain pathogenic strains. A large spectrum of antimicrobial resistances, some of which are intrinsic, has been found in vibrios isolated from seafood or food-borne infections in Europe. Genes conferring resistance to medically important antimicrobials and associated with mobile genetic elements are increasingly detected in vibrios. Temperature and salinity are the most relevant drivers for Vibrio abundance in the aquatic environment. It is anticipated that the occurrence and levels of the relevant Vibrio spp. in seafood will increase in response to coastal warming and extreme weather events, especially in low-salinity/brackish waters. While some measures, like high-pressure processing, irradiation or depuration reduce the levels of Vibrio spp. in seafood, maintaining the cold chain is important to prevent their growth. Available risk assessments addressed V. parahaemolyticus in various types of seafood and V. vulnificus in raw oysters and octopus. A quantitative microbiological risk assessment relevant in an EU context would be V. parahaemolyticus in bivalve molluscs (oysters), evaluating the effect of mitigations, especially in a climate change scenario. Knowledge gaps related to Vibrio spp. in seafood and aquatic environments are identified and future research needs are prioritised.