Future directions for One Health research: Regional and sectoral gaps

Implementation of a One Health approach varies considerably between different geographical regions and remains challenging to implement without greater inclusivity of different disciplinary capacity and expertise. We performed comparative analyses of abstracts presented at the 1st World One Health Congress (WOHC 2011) and 6th WOHC (2020) to explore and describe the evolving demographics and disciplinary scope of One Health research. We classified abstracts into six One Health research categories and twenty-three subcategories. We also recorded corresponding authors' country and regional affiliation as well as study country (i.e., the country in which the research was conducted) to explore potential asymmetries between funding recipients and study subjects. The WOHC has seen a significant expansion in participation over the last 10 years. The numbers of abstracts accepted to the Congress increased threefold over the last decade (i.e., 302 abstracts in 2010, and 932 abstracts in 2020). At both Congresses, "Disease Surveillance" accounted for the largest proportion (105/302 (35%) and 335/932 (36%) in 2010 and 2020, respectively) of all abstracts accepted. However, "Environmental and Ecological Issues" (33/302 (10%) and 94/932 (11%)), and "Sustainable Food Systems" (19/302 (6%) and 44/932 (4%)) were less well-represented categories of One Health research in both 1st and 6th WOHC respectively. In contrast, "Antimicrobial Resistance" related research increased substantially over time (4/302 (1%) in 2011) and (119/932 (13%) in 2020). There were also differences in the type of research by authors based in "Very High Human Development" index countries compared to "Medium and Low Human Development. "Public Policy" dominated the former, whereas "Disease Surveillance" dominated the latter, suggesting potential regional differences regarding One Health research priorities. The results of the study highlight potential regional gaps and differences in One Health research priorities, with respect to emphasis on operational (surveillance) versus strategic (policy) One Health activities.

Navigating Storms: Examining Vultures’ Behavior in Response to Extreme Weather Events

Extreme weather events such as hurricanes and tornadoes have been found to change the spatial and temporal abundance of raptors by decreasing survival and forcing the emigration of individuals, or by increasing habitat heterogeneity and facilitating recolonization of disturbed areas. Nonetheless, little is known about how extreme weather events could affect raptors’ movements and their space use in areas disturbed by large-scale weather events. We studied how extreme weather affected the movements of black and turkey vultures (Coragyps atratus and Cathartes aura, respectively) in Mississippi, USA, facing Hurricane Zeta in November 2020, winter storm Viola in February 2021, and tornados MS-43 and MS-44 in May 2021. We GPS-tracked 28 vultures in the paths of these events. We compared movement rates, net-squared displacements, and use of forest cover, before, during, and after the events. Since storm avoidance behavior has been observed in other birds, we expected that vultures would shift their movements out of the path of these events before storms hit. Further, we forecasted that vultures would make greater use of forested areas as protection against harsh conditions such as strong winds and heavy rain. Vultures responded differently to each weather event; they shifted their movements out of the predicted path of the hurricane and tornadoes but not the snowstorm. These findings reveal that both species use avoidance behavior and adjust their navigation and hazard detection accordingly. Avoidance behavior was more pronounced in turkey vultures than in black vultures. In general, vultures did not make greater use of forest areas as we expected, but turkey vultures did select forest areas during the snowstorm. We propose that olfaction and audition may be key in vultures’ response to extreme weather events.

First Report of Babesia gibsoni in Cats in China

As there are few studies of Babesia spp. infection in cats in China, or anywhere in the world, the aim of this study was to explore the epidemic features of babesiosis in pet cats in China. In total, 429 blood samples were randomly collected in four different geographical regions. The 18S rRNA gene fragment of Babesia spp. was amplified by nest polymerase chain reaction (PCR), and haplotype and phylogenetic analysis of Babesia were performed to analyze the relationship of this protozoa. The total positive rate of infection was 2.8%. BLAST analysis indicated that Babesia gibsoni was detected in 12 cats. Among these, 4.3%, 3.1%, 0.8% and 2.0% were from Chongqing, Fujian, Hubei and Shandong, respectively. Haplotype and phylogenetic analysis showed that there were nine haplotypes and no obvious genetic variation among B. gibsoni populations. This is the first report of B. gibsoni in cats in China. These findings will be helpful for understanding the epidemiology of Babesia spp. in China, and provide a foundation for developing effective preventative strategies.

The COVID-19 pandemic is intricately linked to biodiversity loss and ecosystem health

The ongoing COVID-19 pandemic, caused by zoonotic SARS-CoV-2, has important links to biodiversity loss and ecosystem health. These links range from anthropogenic activities driving zoonotic disease emergence and extend to the pandemic affecting biodiversity conservation, environmental policy, ecosystem services, and multiple conservation facets. Crucially, such effects can exacerbate the initial drivers, resulting in feedback loops that are likely to promote future zoonotic disease outbreaks. We explore these feedback loops and relationships, highlighting known and potential zoonotic disease emergence drivers (eg, land-use change, intensive livestock production, wildlife trade, and climate change), and discuss direct and indirect effects of the ongoing pandemic on biodiversity loss and ecosystem health. We stress that responses to COVID-19 must include actions aimed at safeguarding biodiversity and ecosystems, in order to avoid future emergence of zoonoses and prevent their wide-ranging effects on human health, economies, and society. Such responses would benefit from adopting a One Health approach, enhancing cross-sector, transboundary communication, as well as from collaboration among multiple actors, promoting planetary and human health.

Characterization of orange-spotted grouper (Epinephelus coioides) interferon regulatory factor 4 regulated by heat shock factor 1 during heat stress in response to antiviral immunity

Interferon regulatory factor 4 (IRF4), in conjunction with thermogenic regulation, is a negative regulator of immune responses. Therefore, we examined whether temperature changes regulated the antiviral response of IRF4 in nervous necrosis virus (NNV)-infected orange-spotted groupers. We found that osgIRF4 mRNA expression was responsive to poly I:C stimulation and NNV infection. In vitro overexpression of osgIRF4 caused a marked decrease in the promoter activity of the antiviral protein Mx1, and magnified NNV replication. Notably, we showed that the IAD domain of osgIRF4 exerted a dominant inhibitory effect on the Mx1 promoter. Furthermore, on exposure to high temperatures, the action of osgIRF4 was dependent on heat shock factor 1 (HSF1) expression. Additionally, small interfering RNA knockdown of HSF1 abrogated high temperature-mediated osgIRF4 activity. These findings suggest that osgIRF4 is an essential negative regulator of innate antiviral immunity and enhances viral replication during heat stress in the orange-spotted grouper.

Resurrection of inactive microbes and resistome present in the natural frozen world: Reality or myth?

The present world faces a new threat of ancient microbes and resistomes that are locked in the cryosphere and now releasing upon thawing due to climate change and anthropogenic activities. The cryosphere act as the best preserving place for these microbes and resistomes that stay alive for millions of years. Current reviews extensively discussed whether the resurrection of microbes and resistomes existing in these pristine environments is true or just a hype. Release of these ancient microorganisms and naked DNA is of great concern for society as these microbes can either cause infections directly or they can interact with contemporary microorganisms and affect their fitness, survival, and mutation rate. Moreover, the contemporary microorganisms may uptake the unlocked naked DNA, which might transform non-pathogenic microorganisms into deadly antibiotic-resistant microbes. Additionally, the resurrection of glacial microorganisms can cause adverse effects on ecosystems downstream. The release of glacial pathogens and naked DNA is real and can lead to fatal outbreaks; therefore, we must prepare ourselves for the possible reemergence of diseases caused by these microbes. This study provides a scientific base for the adoption of actions by international cooperation to develop preventive measures.

Observations and perceptions of veterinarians and farmers on heartwater distribution, occurrence and associated factors in South Africa

Background

There is currently no scientific evidence regarding the current climatic or other epidemiological factors that could influence the occurrence of heartwater in South Africa.

Objectives

The objective was to determine whether climatic changes or other epidemiological factors influence the occurence of heartwater in South Africa.

Method

A survey was conducted to scrutinise these factors using both veterinarians and farmers working in known areas in which heartwater had previously been confirmed to establish the value of each of these factors. Based on the observations, meaningful tendencies were noted, and conclusions drawn.

Results

These include changes in the spatial distribution of heartwater in many areas, with serious expansion, in some instances, of up to 150 km. In total, 48% of veterinarians and 42% of farmers reported seeing increase in the number of farms affected by heartwater. Climate change as a causative factor indicated by observations of increased average temperatures, milder frosts, less rain and shorter rainy seasons was identified by the majority of farmers but not by as many veterinarians. Respondents in both groups considered vegetation change an important factor. Increasing number of wildlife, especially antelope, was seen as a major factor by most veterinarians and also by many farmers. Both groups identified the movement of livestock and wildlife as an increasingly important factor that should be of major concern for both industries because it leads to the avoidable spread of many diseases apart from heartwater.

Conclusion

Movement controls should be reinstated and reinforced by vigorously enforced legislation. The role of genetically determined resistance or resilience to heartwater infection in ruminants should be investigated. Breeding better adapted animals could provide part of a sustainable approach to the disease.

Thermoprotective molecules to improve oocyte competence under elevated temperature

Heat stress is an environmental factor that challenges livestock by disturbing animal homeostasis. Despite the broad detrimental effects of heat stress on reproductive function, the germline and the early preimplantation embryo are particularly prone. There is extensive evidence that elevated temperature reduces oocyte developmental competence through a series of cellular and molecular damages. Further research revealed that the oocyte respond to stress by activating cellular mechanisms such as heat shock response, unfolded protein response and autophagy to improve survival under heat shock. Such knowledge paved the way for the identification of thermoprotective molecules that alleviate heat-induced oocyte oxidative stress, organelle damage, and apoptosis. Therefore, this review depicts the deleterious effects of heat shock on oocyte developmental competence, heat-induced cellular and molecular changes, outlines pro-survival cellular mechanisms and explores thermoprotective molecules to improve oocyte competence.

Betanodavirus and VER Disease: A 30-year Research Review

The outbreaks of viral encephalopathy and retinopathy (VER), caused by nervous necrosis virus (NNV), represent one of the main infectious threats for marine aquaculture worldwide. Since the first description of the disease at the end of the 1980s, a considerable amount of research has gone into understanding the mechanisms involved in fish infection, developing reliable diagnostic methods, and control measures, and several comprehensive reviews have been published to date. This review focuses on host–virus interaction and epidemiological aspects, comprising viral distribution and transmission as well as the continuously increasing host range (177 susceptible marine species and epizootic outbreaks reported in 62 of them), with special emphasis on genotypes and the effect of global warming on NNV infection, but also including the latest findings in the NNV life cycle and virulence as well as diagnostic methods and VER disease control.

Flavors of Flaviviral RNA Structure: towards an Integrated View of RNA Function from Translation through Encapsidation

For many viruses, RNA is the holder of genetic information and serves as the template for both replication and translation. While host and viral proteins play important roles in viral decision‐making, the extent to which viral RNA (vRNA) actively participates in translation and replication might be surprising. Here, the focus is on flaviviruses, which include common human scourges such as dengue, West Nile, and Zika viruses, from an RNA‐centric viewpoint. In reviewing more recent findings, an attempt is made to fill knowledge gaps and revisit some canonical views of vRNA structures involved in replication. In particular, alternative views are offered on the nature of the flaviviral promoter and genome cyclization, and the feasibility of refining in vitro‐derived models with modern RNA probing and sequencing methods is pointed out. By tracing vRNA structures from translation through encapsidation, a dynamic molecule closely involved in the self‐regulation of viral replication is revealed.

Heat Waves, the New Normal: Summertime Temperature Extremes Will Impact Animals, Ecosystems, and Human Communities

A consequence of climate change is the increased frequency and severity of extreme heat waves. This is occurring now as most of the warmest summers and most intense heat waves ever recorded have been during the past decade. In this review, I describe the ways in which animals and human populations are likely to respond to increased extreme heat, suggest how to study those responses, and reflect on the importance of those studies for countering the devastating impacts of climate change.

Back to the future in a petri dish: Origin and impact of resurrected microbes in natural populations

Current natural populations face new interactions because of the re-emergence of ancient microbes and viruses. These risks come from the re-emergence of pathogens kept in laboratories or from pathogens that are retained in the permafrost, which become available upon thawing due to climate change. We here focus on the effects of such re-emergence in natural host populations based on evolutionary theory of virulence and long-term studies, which investigate host-pathogen adaptations. Pathogens tend to be locally and temporally adapted to their co-occurring hosts, but when pathogens from a different environment or different time enter the host community, the degree to which a new host-pathogen interaction is a threat will depend on the specific genotypic associations, the time lag between the host and the pathogen, and the interactions with native or recent host and pathogen species. Some insights can be obtained from long-term studies using a resurrection ecology approach. These long-term studies based on time-shift experiments are essential to obtain insight into the mechanisms underlying host-pathogen coevolution at several ecological and temporal scales. As past pathogens and their corresponding host(s) can differ in infectivity and susceptibility, strong reciprocal selective pressures can be induced by the pathogen. These strong selective pressures often result in an escalating arms race, but do not necessarily result in increased infectivity over time. Human health can also be impacted by these resurrected pathogens as the majority of emerging infectious diseases are zoonoses, which are infectious diseases originating from animal populations naturally transmitted to humans. The sanitary risk associated with pathogen emergence from different environments (spatial or temporal) depends on a combination of socioeconomic, environmental, and ecological factors that affect the virulence or the pathogenic potential of microbes and their ability to infect susceptible host populations.

First Molecular Detection of Piroplasm Infection in Pet Dogs from Gansu, China

Babesiosis, the hemolytic disease caused by Babesia, which is a tick-transmitted obligate intraerythrocytic protozoan parasite. This disease is responsible for significant mortality and morbidity rates and enormous economic losses to the livestock industry in tropical and subtropical regions worldwide. In this study, blood samples were collected from 141 pet dogs from Gansu, China, and analyzed for Babesia or Theileria spp. infection using specific PCR and sequencing based on 18S rRNA gene fragments. The results indicated that 18S rRNA gene sequences from 11 samples were similar to the 18S rRNA gene sequences in Babesia canis vogeli (2) and Theileria sinensis (9). The total infected rates of B. canis vogeli and T. sinensis were 1.4% (2/141) and 6.4% (9/141), respectively. This represents the first molecular report of T. sinensis in dogs worldwide and of B. canis vogeli in dogs from Gansu province of China. Furthermore, the finding of T. sinensis in dogs may represent the common infection of this parasite occurring in Gansu.

Google dengue trends: An indicator of epidemic behavior. The Venezuelan Case

INTRODUCTION

Dengue Fever is a neglected increasing public health thread. Developing countries are facing surveillance system problems like delay and data loss. Lately, the access and the availability of health-related information on the internet have changed what people seek on the web. In 2004 Google developed Google Dengue Trends (GDT) based on the number of search terms related with the disease in a determined time and place. The goal of this review is to evaluate the accuracy of GDT in comparison with traditional surveillance systems in Venezuela.

METHODS

Weekly epidemic data from GDT, Official Reported Cases (ORC) and Expected Cases (EC) according the Ministry of Health (MH) was obtained Monthly and yearly correlation between GDT and ORC from 2004 until 2014 was obtained. Linear regressions taking the reported cases as dependent variable were calculated.

RESULTS

The overall Pearson correlation between GDT and ORC was r=0.87 (p <0.001), while between ORC and EC according the Ministry of Health (MH) was r=0.33 (p<0.001). After clustering data in epidemic and non-epidemic weeks in comparison with GDT correlation were r=0.86 (p<0.001) and r=0.65 (p <0.001) respectively. Important interannual variation of the epidemic was observed. The model shows a high accuracy in comparison with the EC, particularly when the incidence of the disease is higher.

CONCLUSIONS

This early warning tool can be used as an indicator for other communicable diseases in order to apply effective and timely public health measures especially in the setting of weak surveillance systems.

Genetic diversity and molecular characterization of Babesia motasi-like in small ruminants and ixodid ticks from China

Ovine babesioses, an important tick-borne disease of sheep and goats in China, is caused by the reproduction of intraerythrocytic protozoa of the Babesia genus. Babesia motasi-like is a Babesia parasite that infects small ruminant in China, and two sub-groups of B. motasi-like can be subdivided based on differences in the rhoptry-associated-protein-1 gene. This study aimed to characterize the distribution, epidemiology and genetics of B. motasi-like in animals and ticks. A molecular investigation was carried out from 2009 to 2015 in 16 provinces in China. In total, 1081 blood samples were collected from sheep and goats originating from 27 different regions, and 778 ixodid tick samples were collected from 8 regions; the samples were tested for the presence of B. motasi-like using a specific nested PCR assay based on the rap-1b gene. The results indicated that 139 (12.9%), 91 (8.4%), 48 (4.4%) and 6 (0.7%) of the blood samples were positive for general B. motasi-like, Babesia sp. BQ1 (Lintan and Ningxian), Babesia sp. Tianzhu and Babesia sp. Hebei sub-groups, mixed infections, respectively. Among the collected 778 ixodid ticks (including Haemaphysalis longicornis, Haemaphysalis qinghaiensis, Dermacentor silvarum, Ixodes persulcatus, Rhipicephalus sanguineus and Rhipicephalus (Boophilus) microplus), the most frequently infected with Babesia were D. silvarum and I. persulcatus (35.7%), followed by H. longicornis (26.8%), H. qinghaiensis (24.8%) and R. sanguineus (9.3%). The PCR results were confirmed by DNA sequencing. The positive rates of B. motasi-like infection in ticks were found to be higher in China, compared with previous studies in other countries. B. motasi-like infections have not previously been reported in D. silvarum, I. persulcatus or R. sanguineus. The findings obtained in this study could be used for planning effective control strategies against babesiosis in China.

Genetic characterization and molecular survey of Babesia bovis, Babesia bigemina and Babesia ovata in cattle, dairy cattle and yaks in China

Background

Babesiosis is an important haemoparasitic disease, caused by the infection and subsequent intra-erythrocytic multiplication of protozoa of the genus Babesia that impacts the livestock industry and animal health. The distribution, epidemiology and genetic characterization of B. bigemina, B. bovis, and B. ovata in cattle in China as well as the prevalence of these protozoan agents were assessed.

Methods

A total of 646 blood specimens from cattle, dairy cattle and yaks from 14 provinces were collected and tested for the presence of the three Babesia species via a specific nested PCR assay based on the rap-1 and ama-1 genes. The PCR results were confirmed by DNA sequencing. Gene sequences and the genetic characterization were determined for selected positive samples from each sampling area.

Results

Of a total of 646 samples, 134 (20.7 %), 60 (9.3 %) and 10 (1.5 %) were positive for B. bovis, B. bigemina and B. ovata infections, respectively. Mixed infections were found in 7 of 14 provinces; 43 (6.7 %) samples were infected with B. bovis and B. bigemina. Three samples (0.5 %) exhibited a co-infection with B. bovis and B. ovata, and 6 (0.9 %) were infected with all three parasites. The rap-1a gene of B. bovis indicated a high degree of sequence heterogeneity compared with other published rap-1a sequences worldwide and was 85–100 % identical to B. bovis rap-1a sequences in Chinese isolates. B. bigemina rap-1c and B. ovata ama-1 genes were nearly identical, with 97.8–99.3 % and 97.8–99.6 % sequence identity, respectively, in GenBank.

Conclusions

Positive rates of B. bovis and B. bigemina infection are somewhat high in China. The B. bovis infection in yaks was first reported. The significant sequence heterogeneity in different variants of the rap-1a gene from Chinese B. bovis isolates might be a great threat to the cattle industry if RAP-1a protein is used as immunological antigen against Babesia infections in China. The data obtained in this study can be used to plan effective control strategies against babesiosis in China.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-015-1110-0) contains supplementary material, which is available to authorized users.

One world, one health: the threat of emerging swine diseases. A North American perspective

The predicted expansion of global livestock populations to meet the food and fibre demands of the growing human population raises numerous concerns, including the implications for disease emergence. The evolution of animal production in developed countries has been marked by substantial reduction in farm numbers with correspondingly larger herd sizes, specialization of enterprises, concentration or ownership and vertical integration. Innovations in the structure and operations of swine production have been largely driven by efforts to improve swine health, and the impact of several important swine diseases has declined. Productivity in swine production and the safety of pork products have increased markedly. The most significant emerging infectious diseases of pigs over the last decades have been highly host-specific viruses rather than multihost pathogens. While some bacterial pathogens of pigs have increased in importance in modern systems, improved management systems and biosecurity have enabled herd sizes to increase without negative impact on swine health. The most vulnerable scenario for disease emergence in swine, particularly for zoonotic agents, may be rapid expansion and intensification of swine industries in developing countries without incorporating the stringent biosecurity measures and veterinary oversight that have helped maintain the health and productivity of large herds in North America. Factors that may influence disease emergence in the long term include regulatory measures (particularly related to antimicrobial use), genetics and feeding practices.

Climate change and habitat fragmentation drive the occurrence of Borrelia burgdorferi, the agent of Lyme disease, at the northeastern limit of its distribution

Lyme borreliosis is rapidly emerging in Canada, and climate change is likely a key driver of the northern spread of the disease in North America. We used field and modeling approaches to predict the risk of occurrence of Borrelia burgdorferi, the bacteria causing Lyme disease in North America. We combined climatic and landscape variables to model the current and future (2050) potential distribution of the black-legged tick and the white-footed mouse at the northeastern range limit of Lyme disease and estimated a risk index for B. burgdorferi from these distributions. The risk index was mostly constrained by the distribution of the white-footed mouse, driven by winter climatic conditions. The next factor contributing to the risk index was the distribution of the black-legged tick, estimated from the temperature. Landscape variables such as forest habitat and connectivity contributed little to the risk index. We predict a further northern expansion of B. burgdorferi of approximately 250–500 km by 2050 – a rate of 3.5–11 km per year – and identify areas of rapid rise in the risk of occurrence of B. burgdorferi. Our results will improve understanding of the spread of Lyme disease and inform management strategies at the most northern limit of its distribution.

The climate change-infectious disease nexus: is it time for climate change syndemics?

Conceptualizing climate as a distinct variable limits our understanding of the synergies and interactions between climate change and the range of abiotic and biotic factors, which influence animal health. Frameworks such as eco-epidemiology and the epi-systems approach, while more holistic, view climate and climate change as one of many discreet drivers of disease. Here, I argue for a new paradigmatic framework: climate-change syndemics. Climate-change syndemics begins from the assumption that climate change is one of many potential influences on infectious disease processes, but crucially is unlikely to act independently or in isolation; and as such, it is the inter-relationship between factors that take primacy in explorations of infectious disease and climate change. Equally importantly, as climate change will impact a wide range of diseases, the frame of analysis is at the collective rather than individual level (for both human and animal infectious disease) across populations.

The PathoChip, a functional gene array for assessing pathogenic properties of diverse microbial communities

Pathogens present in the environment pose a serious threat to human, plant and animal health as evidenced by recent outbreaks. As many pathogens can survive and proliferate in the environment, it is important to understand their population dynamics and pathogenic potential in the environment. To assess pathogenic potential in diverse habitats, we developed a functional gene array, the PathoChip, constructed with key virulence genes related to major virulence factors, such as adherence, colonization, motility, invasion, toxin, immune evasion and iron uptake. A total of 3715 best probes were selected from 13 virulence factors, covering 7417 coding sequences from 1397 microbial species (2336 strains). The specificity of the PathoChip was computationally verified, and approximately 98% of the probes provided specificity at or below the species level, proving its excellent capability for the detection of target sequences with high discrimination power. We applied this array to community samples from soil, seawater and human saliva to assess the occurrence of virulence genes in natural environments. Both the abundance and diversity of virulence genes increased in stressed conditions compared with their corresponding controls, indicating a possible increase in abundance of pathogenic bacteria under environmental perturbations such as warming or oil spills. Statistical analyses showed that microbial communities harboring virulence genes were responsive to environmental perturbations, which drove changes in abundance and distribution of virulence genes. The PathoChip provides a useful tool to identify virulence genes in microbial populations, examine the dynamics of virulence genes in response to environmental perturbations and determine the pathogenic potential of microbial communities.

The ecology of emerging infectious diseases in migratory birds: an assessment of the role of climate change and priorities for future research

Pathogens that are maintained by wild birds occasionally jump to human hosts, causing considerable loss of life and disruption to global commerce. Preliminary evidence suggests that climate change and human movements and commerce may have played a role in recent range expansions of avian pathogens. Since the magnitude of climate change in the coming decades is predicted to exceed climatic changes in the recent past, there is an urgent need to determine the extent to which climate change may drive the spread of disease by avian migrants. In this review, we recommend actions intended to mitigate the impact of emergent pathogens of migratory birds on biodiversity and public health. Increased surveillance that builds upon existing bird banding networks is required to conclusively establish a link between climate and avian pathogens and to prevent pathogens with migratory bird reservoirs from spilling over to humans.

Simultaneous detection of piroplasma infections in field Haemaphysalis qinghaiensis ticks by reverse line blotting

Piroplasmosis is caused by tick-borne haemoprotozoan parasites in the genera of Theileria and Babesia, in which numbers of agents are highly pathogenic for cattle, sheep and goats. We developed a reverse line blot (RLB) assay for detection and differentiation of four different parasites, in which 18S ribosomal RNA gene sequence was amplified with a set of universal primers specific for all members in the genera of Theileria and Babesia; and the probes were designed on the basis of hypervariable region 4 (V4 region) of 18S rRNA gene. Three Theileria and one Babesia can be detected simultaneously on this system and it was sensitive to detect a parasitemia level between 10(-5) and 10(-8)%. A total of 149 Haemaphysalis qinghaiensis ticks collected from Lintan County of Gannan Tibetan Autonomous Region was tested by RLB. Among these, 136 tick samples were also tested by a nested PCR assay developed previously. After comparison of these results, it showed that more T. luwenshuni was detected in RLB assay, while more T. uilenbergi was detected in H. qinghaiensis ticks by nested PCR. The RLB has shown capability for simultaneous detection of four species of piroplasm in H. qinghaiensis ticks, indicating its usefulness for epidemiological studies of piroplasmosis.

Umatilla virus genome sequencing and phylogenetic analysis: identification of stretch lagoon orbivirus as a new member of the Umatilla virus species

The genus Orbivirus, family Reoviridae, includes 22 species of viruses with genomes composed of ten segments of linear dsRNA that are transmitted between their vertebrate hosts by insects or ticks, or with no identified vectors. Full-genome sequence data are available for representative isolates of the insect borne mammalian orbiviruses (including bluetongue virus), as well as a tick borne avian orbivirus (Great Island virus). However, no sequence data are as yet available for the mosquito borne avian orbiviruses.We report full-length, whole-genome sequence data for Umatilla virus (UMAV), a mosquito borne avian orbivirus from the USA, which belongs to the species Umatilla virus. Comparisons of conserved genome segments 1, 2 and 8 (Seg-1, Seg-2 and Seg-8) - encoding the polymerase-VP1, sub-core 'T2' protein and core-surface 'T13' protein, respectively, show that UMAV groups with the mosquito transmitted mammalian orbiviruses. The highest levels of sequence identity were detected between UMAV and Stretch Lagoon orbivirus (SLOV) from Australia, showing that they belong to the same virus species (with nt/aa identity of 76.04%/88.07% and 77.96%/95.36% in the polymerase and T2 genes and protein, respectively). The data presented here has assisted in identifying the SLOV as a member of the Umatilla serogroup. This sequence data reported here will also facilitate identification of new isolates, and epidemiological studies of viruses belonging to the species Umatilla virus.

Marine mammals as sentinel species for oceans and human health

The long-term consequences of climate change and potential environmental degradation are likely to include aspects of disease emergence in marine plants and animals. In turn, these emerging diseases may have epizootic potential, zoonotic implications, and a complex pathogenesis involving other cofactors such as anthropogenic contaminant burden, genetics, and immunologic dysfunction. The concept of marine sentinel organisms provides one approach to evaluating aquatic ecosystem health. Such sentinels are barometers for current or potential negative impacts on individual- and population-level animal health. In turn, using marine sentinels permits better characterization and management of impacts that ultimately affect animal and human health associated with the oceans. Marine mammals are prime sentinel species because many species have long life spans, are long-term coastal residents, feed at a high trophic level, and have unique fat stores that can serve as depots for anthropogenic toxins. Marine mammals may be exposed to environmental stressors such as chemical pollutants, harmful algal biotoxins, and emerging or resurging pathogens. Since many marine mammal species share the coastal environment with humans and consume the same food, they also may serve as effective sentinels for public health problems. Finally, marine mammals are charismatic megafauna that typically stimulate an exaggerated human behavioral response and are thus more likely to be observed.

A broad assessment of factors determining Culicoides imicola abundance: modelling the present and forecasting its future in climate change scenarios

Bluetongue (BT) is still present in Europe and the introduction of new serotypes from endemic areas in the African continent is a possible threat. Culicoides imicola remains one of the most relevant BT vectors in Spain and research on the environmental determinants driving its life cycle is key to preventing and controlling BT. Our aim was to improve our understanding of the biotic and abiotic determinants of C. imicola by modelling its present abundance, studying the spatial pattern of predicted abundance in relation to BT outbreaks, and investigating how the predicted current distribution and abundance patterns might change under future (2011-2040) scenarios of climate change according to the Intergovernmental Panel on Climate Change. C. imicola abundance data from the bluetongue national surveillance programme were modelled with spatial, topoclimatic, host and soil factors. The influence of these factors was further assessed by variation partitioning procedures. The predicted abundance of C. imicola was also projected to a future period. Variation partitioning demonstrated that the pure effect of host and topoclimate factors explained a high percentage (>80%) of the variation. The pure effect of soil followed in importance in explaining the abundance of C. imicola. A close link was confirmed between C. imicola abundance and BT outbreaks. To the best of our knowledge, this study is the first to consider wild and domestic hosts in predictive modelling for an arthropod vector. The main findings regarding the near future show that there is no evidence to suggest that there will be an important increase in the distribution range of C. imicola; this contrasts with an expected increase in abundance in the areas where it is already present in mainland Spain. What may be expected regarding the future scenario for orbiviruses in mainland Spain, is that higher predicted C. imicola abundance may significantly change the rate of transmission of orbiviruses.

Megacities as sources for pathogenic bacteria in rivers and their fate downstream

Poor sanitation, poor treatments of waste water, as well as catastrophic floods introduce pathogenic bacteria into rivers, infecting and killing many people. The goal of clean water for everyone has to be achieved with a still growing human population and their rapid concentration in large cities, often megacities. How long introduced pathogens survive in rivers and what their niches are remain poorly known but essential to control water-borne diseases in megacities. Biofilms are often niches for various pathogens because they possess high resistances against environmental stress. They also facilitate gene transfers of antibiotic resistance genes which become an increasing health problem. Beside biofilms, amoebae are carriers of pathogenic bacteria and niches for their survival. An overview about our current understanding of the fate and niches of pathogens in rivers, the multitude of microbial community interactions, and the impact of severe flooding, a prerequisite to control pathogens in polluted rivers, is given.

Communicable Diseases: Achievements and Challenges for Public Health

The past two centuries have seen enormous achievements in control of infectious diseases, previously the leading cause of death, in large measure due to sanitation and food safety, vaccines, antibiotics and improved nutrition. This has led people to put their faith in the notion that medical science would succeed in overcoming the remaining obstacles. Vaccination has eradicated smallpox, nearly eradicated poliomyelitis and greatly reduced many other highly dangerous infections such as diphtheria, tetanus and measles. New diseases such as HIV and new forms of influenza have taken both professional and popular opinion by surprise and have renewed the challenges before the world public health community. Emergence of antibiotic-resistant strains of common organisms due to overuse of antibiotics and lack of vaccines for many dangerous microorganisms poses problems to humanity. This stresses the need for new vaccines, effective antibiotics and strengthened environmental control measures. New knowledge of the microbiological origins of cancers such as that of the cervix, stomach and liver have strengthened primary prevention and brought hope that new cures will be found for other chronic diseases of infectious origin. Tragically long delays in adopting "new" and cost effective vaccines cause hundreds of thousands of preventable deaths each year in developing and mid-level developed countries. Gains are being made in control of many tropical diseases, but malaria, tuberculosis and other infectious diseases remain enormous global problems. Research and acquisition of new knowledge, risk communication, application of currently available means and fair distribution will be great challenges to public health in the coming decades.