The UK's suitability for Aedes albopictus in current and future climates.

The Asian tiger mosquito Aedes albopictus is able to transmit various pathogens to humans and animals and it has already caused minor outbreaks of dengue and chikungunya in southern Europe. Alarmingly, it is spreading northwards and its eggs have been found in the UK in 2016 and 2017. Climate-driven models can help to analyse whether this originally subtropical species could become established in northern Europe. But so far, these models have not considered the impact of the diurnal temperature range (DTR) experienced by mosquitoes in the field. Here, we describe a dynamical model for the life cycle of Ae. albopictus, taking into account the DTR, rainfall, photoperiod and human population density. We develop a new metric for habitat suitability and drive our model with different climate data sets to analyse the UK's suitability for this species. For now, most of the UK seems to be rather unsuitable, except for some densely populated and high importation risk areas in southeast England. But this picture changes in the next 50 years: future scenarios suggest that Ae. albopictus could become established over almost all of England and Wales, indicating the need for continued mosquito surveillance.

The effect of temperature, farm density and foot-and-mouth disease restrictions on the 2007 UK bluetongue outbreak.

In 2006, bluetongue (BT), a disease of ruminants, was introduced into northern Europe for the first time and more than two thousand farms across five countries were affected. In 2007, BT affected more than 35,000 farms in France and Germany alone. By contrast, the UK outbreak beginning in 2007 was relatively small, with only 135 farms in southeast England affected. We use a model to investigate the effects of three factors on the scale of BT outbreaks in the UK: (1) place of introduction; (2) temperature; and (3) animal movement restrictions. Our results suggest that the UK outbreak could have been much larger had the infection been introduced into the west of England either directly or as a result of the movement of infected animals from southeast England before the first case was detected. The fact that air temperatures in the UK in 2007 were marginally lower than average probably contributed to the UK outbreak being relatively small. Finally, our results indicate that BT movement restrictions are effective at controlling the spread of infection. However, foot-and-mouth disease restrictions in place before the detection and control of BT in 2007 almost certainly helped to limit BT spread prior to its detection.

Fasciola and fasciolosis in ruminants in Europe: Identifying research needs.

Fasciola hepatica is a trematode parasite with a global distribution, which is responsible for considerable disease and production losses in a range of food producing species. It is also identified by WHO as a re-emerging neglected tropical disease associated with endemic and epidemic outbreaks of disease in human populations. In Europe, F. hepatica is mostly associated with disease in sheep, cattle and goats. This study reviews the most recent advances in our understanding of the transmission, diagnosis, epidemiology and the economic impact of fasciolosis. We also focus on the impact of the spread of resistance to anthelmintics used to control F. hepatica and consider how vaccines might be developed and applied in the context of the immune-modulation driven by the parasite. Several major research gaps are identified which, when addressed, will contribute to providing focussed and where possible, bespoke, advice for farmers on how to integrate stock management and diagnosis with vaccination and/or targeted treatment to more effectively control the parasite in the face of increasing the prevalence of infection and spread of anthelmintic resistance that are likely to be exacerbated by climate change.

The role of climate change in a developing threat: the case of bluetongue in Europe.

There is a solid theoretical basis for expecting climate change to have a considerable effect on the infectious diseases of humans, animals and plants. Vector-borne diseases are the most likely to be affected. It is, however, rare to observe such impacts, as diseases are also influenced by many other drivers, some of which may have stronger effects over shorter time scales than climate change. Nevertheless, there is evidence that our warming climate has already influenced some animal diseases, of which bluetongue is considered a prime example. Bluetongue emerged dramatically in southern Europe after 1998 and in northern Europe from 2006. While the speed and scale of this emergence is a challenge to explain, there is evidence, principally from the development of climate-driven models, that recent climate change has played a significant role. Climate-driven models point to an increase in the risk of bluetongue transmission in Europe in recent decades, caused by an increased suitability of parts of southern Europe for the Afro-tropical biting midge, Culicoides imicola, as well as an increase in the vectorial capacity of indigenous Culicoides vectors in northern Europe. Farm-to-farm transmission models of bluetongue in England and Wales under predicted climatic conditions further suggest that, under high-emission scenarios, the scale of future outbreaks could far exceed those experienced to date. The role of climate change in the developing threat of animal disease is, therefore, likely to be economically and socially costly, unless lower emission targets can be set and followed.

Nombre d'arguments théoriques sérieux confirment l'ampleur des effets du changement climatique sur les maladies infectieuses affectant l'être humain, les animaux et les végétaux. Les maladies à transmission vectorielle sont probablement les plus sujettes à cette influence. Toutefois, il est très rare de pouvoir observer ces effets directement, dans la mesure où d'autres facteurs exercent également une influence sur les maladies, dont certains ont des effets plus marquants et plus rapides que le changement climatique. L'influence du réchauffement climatique sur certaines maladies animales a néanmoins été prouvée ; à ce titre, le cas de la fièvre catarrhale ovine est considéré comme exemplaire. La fièvre catarrhale ovine a fait son apparition en Europe méridionale après 1998, puis en Europe du Nord à partir de 2006. Si la rapidité et l'envergure de cette émergence sont difficiles à expliquer, plusieurs démonstrations, recourant pour la plupart à des modèles axés sur le climat font état du rôle important joué par le changement climatique. Les modèles axés sur le climat font ressortir un risque accru de transmission de la fièvre catarrhale ovine en Europe au cours des dernières décennies, associé, d'une part, à l'adéquation croissante de régions entières de l'Europe méridionale vis-à-vis du moucheron afro-tropical Culicoides imicola et, d'autre part, à l'accroissement de la capacité vectorielle des vecteurs Culicoides autochtones dans le nord de l'Europe. D'après les études basées sur des modèles de transmission de la fièvre catarrhale ovine entre exploitations en Angleterre et au Pays de Galles, dans les conditions climatiques prévisibles, il apparaît qu'en cas de fortes émissions, l'ordre de grandeur des foyers futurs serait considérablement plus élevé que dans les épisodes que nous avons connus jusqu'à présent. Par conséquent, le rôle du changement climatique dans les menaces évolutives de santé animale risque d'avoir un coût économique et social élevé, à moins que des objectifs de réduction de l'émission soient mis en place et fassent l'objet d'un suivi approprié.

Existen sólidas bases teóricas para prever que el cambio climático tendrá efectos considerables en las enfermedades infecciosas que afectan al hombre, los animales o las plantas. Las que más probablemente se verán afectadas son las enfermedades transmitidas por vectores. Sin embargo, rara vez pueden observarse tales efectos, pues hay otros muchos factores que influyen en las enfermedades, algunos de los cuales, a una escala temporal más breve, pueden tener una influencia más marcada que el cambio climático. Aun así, hay pruebas de que el clima, en pleno proceso de calentamiento, ya ha incidido en algunas enfermedades animales, de las que la lengua azul se considera un perfecto ejemplo. La lengua azul hizo una espectacular aparición en el sur de Europa a partir de 1998, y en la Europa septentrional a partir de 2006. Aunque resulta difícil explicar la velocidad y las proporciones de tal aparición, existen sólidos indicios, obtenidos principalmente de la elaboración de modelos regidos por variantes climáticas, de que el reciente cambio climático ha cumplido una función importante. Estos modelos apuntan a un incremento del riesgo de transmisión de la lengua azul en Europa en los últimos decenios, lo que se explica por las condiciones más propicias al jején afrotropical, Culicoides imicola, que ofrecen ciertas partes de Europa meridional y por un aumento de la capacidad vectorial de los Culicoides autóctonos del norte de Europa. Los modelos de transmisión de la lengua azul entre explotaciones agropecuarias de Inglaterra y Gales en las condiciones climáticas predichas indican además que, en la hipótesis de un elevado volumen de emisiones, los futuros brotes pueden revestir una escala muy superior a cuanto hemos conocido hasta ahora. Por consiguiente, a menos que se logre establecer y cumplir objetivos de emisiones menos cuantiosas, es probable que el cambio climático resulte económica y socialmente gravoso por su incidencia en la creciente amenaza que plantean las enfermedades animales.