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In the Anthropocene, in which we now live, climate change is impacting most life on Earth. Microorganisms support the existence of all higher trophic life forms. To understand how humans and other life forms on Earth (including those we are yet to discover) can withstand anthropogenic climate change, it is vital to incorporate knowledge of the microbial ‘unseen majority’. We must learn not just how microorganisms affect climate change (including production and consumption of greenhouse gases) but also how they will be affected by climate change and other human activities. This Consensus Statement documents the central role and global importance of microorganisms in climate change biology. It also puts humanity on notice that the impact of climate change will depend heavily on responses of microorganisms, which are essential for achieving an environmentally sustainable future.

There is concern that climate change will lead to expansion of vector-borne diseases as, of all disease types, they are the most sensitive to climate drivers1. Such expansion may threaten human health, and food security via effects on animal and crop health. Here we quantify the potential impact of climate change on a vector-borne disease of livestock, bluetongue, which has emerged in northern Europe in response to climate change2–4, affecting tens of thousands of farms at huge financial cost and causing the deaths of millions of animals5. We derive future disease risk trends for northern Europe, and use a detailed spatial transmission model6to simulate outbreaks in England and Wales under future climatic conditions, using an ensemble of five downscaled general circulation models7. By 2100, bluetongue risk extends further north, the transmission season lengthens by up to three months and outbreaks are larger on average. A 1 in 20-year outbreak at present-day temperatures becomes typical by the 2070s under the highest greenhouse gas emission scenario. However, animal movement restrictions are sufficient to prevent truly devastating outbreaks. Disease transmission uncertainty dominates over climate uncertainty, even at the longest prediction timescales. Our results suggest that efficient detection and control measures to limit the spread of vector-borne diseases will be increasingly vital in future, warmer climates.

Tick cell lines are increasingly used in many fields of tick and tick-borne disease research. The Tick Cell Biobank was established in 2009 to facilitate the development and uptake of these unique and valuable resources. As well as serving as a repository for existing and new ixodid and argasid tick cell lines, the Tick Cell Biobank supplies cell lines and training in their maintenance to scientists worldwide and generates novel cultures from tick species not already represented in the collection. Now part of the Institute of Infection and Global Health at the University of Liverpool, the Tick Cell Biobank has embarked on a new phase of activity particularly targeted at research on problems caused by ticks, other arthropods and the diseases they transmit in less-developed, lower- and middle-income countries. We are carrying out genotypic and phenotypic characterisation of selected cell lines derived from tropical tick species. We continue to expand the culture collection, currently comprising 63 cell lines derived from 18 ixodid and argasid tick species and one each from the sand fly Lutzomyia longipalpisand the biting midge Culicoides sonorensis, and are actively engaging with collaborators to obtain starting material for primary cell cultures from other midge species, mites, tsetse flies and bees. Outposts of the Tick Cell Biobank will be set up in Malaysia, Kenya and Brazil to facilitate uptake and exploitation of cell lines and associated training by scientists in these and neighbouring countries. Thus the Tick Cell Biobank will continue to underpin many areas of global research into biology and control of ticks, other arthropods and vector-borne viral, bacterial and protozoan pathogens.

A number of broiler flocks with respiratory disease and high mortality in five broiler farms in Libya were sampled for detection of infectious bronchitis virus (IBV). Twelve IBV strains from these farms were detected by reverse transcription polymerase chain reaction (RT-PCR) and differentiated by nucleotide sequencing of the hypervariable region of the S1 gene. A pair-wise comparison of the sequences showed two distinctive patterns. Those from farms 1, 2, 4 and 5, formed a separate cluster with 94–99% relatedness to the Egyptian IBV strains CK/Eg/BSU-2/2011, CK/Eg/BSU-3/2011 and Eg/1212B. Sequences from the farm 3 formed another cluster with 100% relatedness to Eg/CLEVB-2/IBV/012 and IS/1494/06. This appears to be the first report on the co-circulation these variant IBVs in Libya.

AbstractA number of broiler flocks with respiratory disease and high mortality in five broiler farms in Libya were sampled for detection of infectious bronchitis virus (IBV). Twelve IBV strains from these farms were detected by reverse transcription polymerase chain reaction (RT-PCR) and differentiated by nucleotide sequencing of the hypervariable region of the S1 gene. A pair-wise comparison of the sequences showed two distinctive patterns. Those from farms 1, 2, 4 and 5, formed a separate cluster with 94–99% relatedness to the Egyptian IBV strains CK/Eg/BSU-2/2011, CK/Eg/BSU-3/2011 and Eg/1212B. Sequences from the farm 3 formed another cluster with 100% relatedness to Eg/CLEVB-2/IBV/012 and IS/1494/06. This appears to be the first report on the co-circulation these variant IBVs in Libya.

The Asian tiger mosquito (Aedes albopictus) is an invasive species that has the potential to transmit infectious diseases such as dengue and chikungunya fever. Using high-resolution observations and regional climate model scenarios for the future, we investigated the suitability of Europe for A. albopictususing both recent climate and future climate conditions. The results show that southern France, northern Italy, the northern coast of Spain, the eastern coast of the Adriatic Sea and western Turkey were climatically suitable areas for the establishment of the mosquito during the 1960–1980s. Over the last two decades, climate conditions have become more suitable for the mosquito over central northwestern Europe (Benelux, western Germany) and the Balkans, while they have become less suitable over southern Spain. Similar trends are likely in the future, with an increased risk simulated over northern Europe and slightly decreased risk over southern Europe. These distribution shifts are related to wetter and warmer conditions favouring the overwintering of A. albopictusin the north, and drier and warmer summers that might limit its southward expansion.

Vector-borne diseases are among those most sensitive to climate because the ecology of vectors and the development rate of pathogens within them are highly dependent on environmental conditions. Bluetongue (BT), a recently emerged arboviral disease of ruminants in Europe, is often cited as an illustration of climate's impact on disease emergence, although no study has yet tested this association. Here, we develop a framework to quantitatively evaluate the effects of climate on BT's emergence in Europe by integrating high-resolution climate observations and model simulations within a mechanistic model of BT transmission risk. We demonstrate that a climate-driven model explains, in both space and time, many aspects of BT's recent emergence and spread, including the 2006 BT outbreak in northwest Europe which occurred in the year of highest projected risk since at least 1960. Furthermore, the model provides mechanistic insight into BT's emergence, suggesting that the drivers of emergence across Europe differ between the South and the North. Driven by simulated future climate from an ensemble of 11 regional climate models, the model projects increase in the future risk of BT emergence across most of Europe with uncertainty in rate but not in trend. The framework described here is adaptable and applicable to other diseases, where the link between climate and disease transmission risk can be quantified, permitting the evaluation of scale and uncertainty in climate change's impact on the future of such diseases.

Avian malaria has caused mortalities in captive penguins worldwide and it is a conservation threat for some wild penguins. The experience of staff working on penguins is highly valuable for the improvement of captivity conditions. An online questionnaire was designed to collect avian malaria information in penguins in the UK. Volunteers with diverse experience reviewed it for scientific value and clarity, and it was supported by the British and Irish Association of Zoos and Aquariums. Forty‐two institutions were contacted by email, obtaining 27 complete and five partial responses. Eighteen institutions reported avian malaria in 38 suspected and 37 confirmed outbreaks in the past 20 years, mainly occurring in the summer and recent years. Proportional risk was higher in the south east region of England. Humboldt and African penguins were more commonly affected, and prevalence was mostly low or medium, but lethality was high. Different treatment protocols were reported with inconsistent outcomes. Penguins’ susceptibility, their translocation across institutions, and the wide distribution of avian malaria make this disease a constant threat. Preventive and control measures are recommended, including testing for early diagnosis and treatment, avoiding prolonged stressful events in penguins, and monitoring and controlling mosquito vectors.

Schmallenberg virus (SBV) is an orthobunyavirus, carried by Culicoidesbiting midges, that causes reproductive problems in adult ruminants when infected during their gestation period. SBV was first detected in ruminants in the UK in 2011/2012 and then again in 2016. The reason behind the 2016 re‐emergence of SBV is unknown, but one possibility is that it can be maintained in wildlife, such as deer. SBV has been detected at high seroprevalence in deer in a number of European countries, but only once in the UK in a single region. The purpose of this study was to survey wild deer across Great Britain for recent evidence of SBV. Deer hunters were recruited for the purpose of providing postmortem blood samples to be tested for SBV antibodies. The seroprevalence of SBV in the British wild deer population was 13.8 per cent; found in red, roe, muntjac and fallow deer species, with more in deer further south. These results support the growing concern that SBV is now endemic in Great Britain and highlight the need to know the role of wildlife in SBV transmission.

Schmallenberg virus (SBV) causes abortions, stillbirths and fetal malformations in naïve ruminants. The impact of the initial outbreak (2011/2012) on British sheep farms has been previously investigated, with higher farmer perceived impacts and increased lamb and ewe mortality reported on SBV‐affected farms. After several years of low, or no, circulation the UK sheep flock once again became vulnerable to SBV infection. Re‐emergence was confirmed in autumn 2016. This study reports the analysis of a questionnaire designed to determine the farm‐level impact of SBV on the 2016/2017 UK lambing period. Higher neonatal lamb mortality, dystocia and associated ewe deaths, and higher perceived impacts on sheep welfare, flock financial performance and farmer emotional wellness were reported on SBV confirmed (n=59) and SBV suspected (n=82), than SBV not suspected (n=74) farms. Additionally, although few farmers (20.4 per cent) reported previously vaccinating against SBV, the majority (78.3 per cent) stated they would vaccinate if purchasing at less than £1 per dose. These results are largely comparable to the findings reported for the 2011/2012 outbreak, highlighting the ongoing impact of SBV on sheep farms. If SBV continues to re‐emerge cyclically, the economic and animal welfare costs to the UK sheep farming industry will continue.

Increased globalisation and climate change have led to concern about the increasing risk of arthropod‐borne virus (arbovirus) outbreaks globally. An outbreak of equine arboviral disease in northern Europe could impact significantly on equine welfare, and result in economic losses. Early identification of arboviral disease by horse owners may help limit disease spread. In order to determine what horse owners understand about arboviral diseases of horses and their vectors, the authors undertook an open, cross‐sectional online survey of UK horse owners. The questionnaire was distributed using social media and a press release and was active between May and July 2016. There were 466 respondents, of whom 327 completed the survey in full. High proportions of respondents correctly identified photographic images of biting midges (71.2 per cent) and mosquitoes (65.4 per cent), yet few were aware that they transmit equine infectious diseases (31.4 per cent and 35.9 per cent, respectively). Of the total number of respondents, only 7.4 per cent and 16.2 per cent correctly named a disease transmitted by biting midges and mosquitoes, respectively. Only 13.1 per cent and 12.5 per cent of participants identified specific clinical signs of African horse sickness (AHS) and West Nile virus (WNV), respectively. This study demonstrates that in the event of heightened disease risk educational campaigns directed towards horse owners need to be implemented, focussing on disease awareness, clinical signs and effective disease prevention strategies.

ABSTRACTFasciola hepaticais a parasitic trematode of global importance in livestock. Control strategies reliant on anthelmintics are unsustainable due to the emergence of drug resistance. Vaccines are under development, but efficacies are variable. Evidence from experimental infection suggests that vaccine efficacy may be affected by parasite-induced immunomodulation. Little is known about the immune response to F. hepaticafollowing natural exposure. Hence, we analyzed the immune responses over time in calves naturally exposed to F. hepaticainfection. Cohorts of replacement dairy heifer calves (n= 42) with no prior exposure to F. hepatica, on three commercial dairy farms, were sampled over the course of a grazing season. Exposure was determined through an F. hepatica-specific serum antibody enzyme-linked immunosorbent assay (ELISA) and fluke egg counts. Concurrent changes in peripheral blood leukocyte subpopulations, lymphocyte proliferation, and cytokine responses were measured. Relationships between fluke infection and immune responses were analyzed by using multivariable linear mixed-effect models. All calves from one farm showed evidence of exposure, while cohorts from the remaining two farms remained negative over the grazing season. A type 2 immune response was associated with exposure, with increased interleukin-4 (IL-4) production, IL-5 transcription, and eosinophilia. Suppression of parasite-specific peripheral blood mononuclear cell (PBMC) proliferation was evident, while decreased mitogen-stimulated gamma interferon (IFN-γ) production suggested immunomodulation, which was not restricted to parasite-specific responses. Our findings show that the global immune response is modulated toward a nonproliferative type 2 state following natural challenge with F. hepatica. This has implications in terms of the timing of the administration of vaccination programs and for host susceptibility to coinfecting pathogens.

In 2011–2012, northern European livestock faced a threat from a newly emerged virus, Schmallenberg virus (SBV), only a few years after a major outbreak of bluetongue serotype 8 (BTV‐8). Like BTV‐8, SBV is transmitted by Culicoidesbiting midges to ruminants and spread throughout Europe. SBV, however, spread faster, reaching the UK within three months of initial discovery. Adult ruminants show only mild, if any, clinical signs; however, infection of naive ruminants by SBV during the vulnerable period of gestation leads to abortions, stillbirths and fetal malformations. Although some data exist for the prevalence of SBV on UK sheep farms early in the outbreak, we have no information on its current status. Is SBV still circulating in the UK? To answer this, the authors designed a freedom from disease study across the southernmost counties of the UK. During autumn 2015, 1444 sheep, from 131 farms, were tested for antibodies against SBV by ELISA; 5 samples from 4 farms were twice found positive by ELISA but were later confirmed negative by virus neutralisation test. As the sheep were born between October 2014 and April 2015, the authors conclude that it is unlikely that SBV is still circulating in the south of England.

The ability of the infectious bronchitis H120 (a Massachusetts strain) and CR88 (a 793B strain) live attenuated vaccine viruses to protect from two Middle East infectious bronchitis virus isolates, IS/885/00-like (IS/885) and IS/1494/06-like (IS/1494) in broiler chicks was investigated. Day-old chicks were separated into three groups, (I) vaccinated with H120 at day-old followed by CR88 at 14 days-old, (II) vaccinated with H120 and CR88 simultaneously at day-old and again with CR88 at 14 days-old, (III) control unvaccinated. At 30 days-old, each of the groups was challenged with virulent IS/885 or IS/1494. Protection was evaluated based on the clinical signs, tracheal and kidney gross lesions and tracheal ciliostasis. Results showed that administering combined live H120 and CR88 vaccines simultaneously at day-old followed by CR88 vaccine at 14 days-old gave more than 80 per cent tracheal ciliary protection from both of the Middle East isolates. In addition, this programme conferred 100 per cent protection from clinical signs and tracheal or kidney lesions. The other vaccination programme, H120 at day-old followed by CR88 at 14 days-old, the tracheal ciliary protection conferred were 60 per cent and 80 per cent from IS/885/00-like and IS/1494/06-like, respectively.