An assessment of Zoonotic and Production Limiting Pathogens in Rusa Deer (Cervus timorensis rusa) from Mauritius

Valuing the contributions of non-native species to people and nature

While decision-making can benefit from considering positive and negative outcomes of change, over the past half-century, research on non-native species has focused predominately on their negative impacts. Here we provide a framework for considering the positive consequences of non-native species relative to relational, instrumental, and intrinsic values. We demonstrate that their beneficial outcomes are common and profoundly important for human well-being. Identified benefits include social cohesion, cultural identity, mental health, food and fuel production, regulation of clean waters, and attenuation of climate change. We argue that long-standing biases against non-native species within the literature have clouded the scientific process and hampered policy advances and sound public understanding. Future research should consider both costs and benefits of non-native species.

Detection of Leptospira interrogans in Wild Sambar Deer (Rusa unicolor), Brazil

Leptospirosis is an emerging zoonotic disease caused by bacteria of the genus Leptospira. Wild animals may present acute disease or become chronic hosts. The present study aimed to identify Leptospira spp. infection and determine circulating serogroups in free-ranging sambar deer (Rusa unicolor) in a fragment of peri-urban tropical forest in northeastern Brazil. Blood samples were collected and subjected to microscopic agglutination testing (MAT) and PCR analysis (genes lipL32 and secY). Anti-Leptospira antibodies were detected in 60% of the animals tested, with serogroups Cynopteri (33.4%), Hebdomadis (22.2%) and Grippotyphosa (22.2%) identified as most prevalent. DNA corresponding to the pathogenic species Leptospira interrogans was detected in 2/15 (13.3%) of the samples tested. Sambar deer experience a high level of exposure to Leptospira spp. in our epidemiological setting. It is important to emphasize the implementation of effective measures (i.e., maintaining habitats and reducing human contact) for the conservation of endangered species.

Paving the way for human vaccination against Rift Valley fever virus: A systematic literature review of RVFV epidemiology from 1999 to 2021

BACKGROUND

Rift Valley fever virus (RVFV) is a lethal threat to humans and livestock in many parts of Africa, the Arabian Peninsula, and the Indian Ocean. This systematic review's objective was to consolidate understanding of RVFV epidemiology during 1999-2021 and highlight knowledge gaps relevant to plans for human vaccine trials.

METHODOLOGY/PRINCIPAL FINDINGS

The review is registered with PROSPERO (CRD42020221622). Reports of RVFV infection or exposure among humans, animals, and/or vectors in Africa, the Arabian Peninsula, and the Indian Ocean during the period January 1999 to June 2021 were eligible for inclusion. Online databases were searched for publications, and supplemental materials were recovered from official reports and research colleagues. Exposures were classified into five groups: 1) acute human RVF cases, 2) acute animal cases, 3) human RVFV sero-surveys, 4) animal sero-surveys, and 5) arthropod infections. Human risk factors, circulating RVFV lineages, and surveillance methods were also tabulated. In meta-analysis of risks, summary odds ratios were computed using random-effects modeling. 1104 unique human or animal RVFV transmission events were reported in 39 countries during 1999-2021. Outbreaks among humans or animals occurred at rates of 5.8/year and 12.4/year, respectively, with Mauritania, Madagascar, Kenya, South Africa, and Sudan having the most human outbreak years. Men had greater odds of RVFV infection than women, and animal contact, butchering, milking, and handling aborted material were significantly associated with greater odds of exposure. Animal infection risk was linked to location, proximity to water, and exposure to other herds or wildlife. RVFV was detected in a variety of mosquito vectors during interepidemic periods, confirming ongoing transmission.

CONCLUSIONS/SIGNIFICANCE

With broad variability in surveillance, case finding, survey design, and RVFV case confirmation, combined with uncertainty about populations-at-risk, there were inconsistent results from location to location. However, it was evident that RVFV transmission is expanding its range and frequency. Gaps assessment indicated the need to harmonize human and animal surveillance and improve diagnostics and genotyping. Given the frequency of RVFV outbreaks, human vaccination has strong potential to mitigate the impact of this now widely endemic disease.

Global Comprehensive Literature Review and Meta-Analysis of Brucella spp. in Swine Based on Publications From 2000 to 2020

Background: Brucellosis, a zoonotic disease, infects various hosts, including swine and humans. It has reemerged in recent years as a public health concern, and current studies on brucellosis infection in swine have been conducted worldwide. However, no meta-analyses of global brucellosis infection in swine have been published. The aim of this study was to provide an overview of Brucella species (spp.) in swine worldwide and the factors associated with its persistence.

Results: We searched seven databases for published epidemiological studies on brucellosis in pigs, including the Chinese National Knowledge Infrastructure, Wanfang Data, SpringerLink, ScienceDirect, Web of Science, the VIP Chinese Journal Database and PubMed. We selected 119 articles published from January 1, 2000 to January 3, 2020 for inclusion in the meta-analysis and analyzed the data using a random-effects model. Funnel plots and Egger's test showed significant publication bias in the included studies. The results of the sensitivity analysis showed that our study was relatively stable and reliable. The prevalence of brucellosis in swine was 2.1% (95% CI: 1.6–2.6), of which the highest infection rate, which was found in Europe, was 17.4% (95% CI: 11.1–24.9). The prevalence in feral pigs (15.0%, 95% CI: 8.4–23.2) was higher than that in domestic pigs (1.1%, 95% CI 0.2–2.5). The prevalence in high-income countries (15.7%, 95% CI 8.0–25.3) was significantly higher than that in middle- (0.8%, 95% CI 0.5–1.1), and low-income countries (0.1%, 95% CI 0.0–0.2). The prevalence was highest in finishing pigs at 4.9% (95% CI 0.9–11.0), and lowest among suckling pigs at 0% (95% CI 0.0–0.5).

Conclusion: The Brucella prevalence in pig herds currently is distributed widely throughout the world. In some countries, swine brucellosis may be a neglected zoonotic disease. We recommend long-term monitoring of the prevalence of brucellosis in domestic and wild pig herds. Attention should also be paid to animal welfare on intensive pig farms; controlling the breeding density may play an important role in reducing the spread of brucellosis among pigs.

Divergent impacts of warming weather on wildlife disease risk across climates

Disease outbreaks among wildlife have surged in recent decades alongside climate change, although it remains unclear how climate change alters disease dynamics across different geographic regions. We amassed a global, spatiotemporal dataset describing parasite prevalence across 7346 wildlife populations and 2021 host-parasite combinations, compiling local weather and climate records at each location. We found that hosts from cool and warm climates experienced increased disease risk at abnormally warm and cool temperatures, respectively, as predicted by the thermal mismatch hypothesis. This effect was greatest in ectothermic hosts and similar in terrestrial and freshwater systems. Projections based on climate change models indicate that ectothermic wildlife hosts from temperate and tropical zones may experience sharp increases and moderate reductions in disease risk, respectively, though the magnitude of these changes depends on parasite identity.

Paratuberculosis: A Potential Zoonosis and a Neglected Disease in Africa

The Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of paratuberculosis, which is an economically important disease of ruminants. The zoonotic role of MAP in Crohn’s disease and, to a lesser extent, in ulcerative colitis, the two major forms of idiopathic inflammatory bowel disease (IIBD), has been debated for decades and evidence continues to mount in support of that hypothesis. The aim of this paper is to present a review of the current information on paratuberculosis in animals and the two major forms of IIBD in Africa. The occurrence, epidemiology, economic significance and “control of MAP and its involvement IIBD in Africa” are discussed. Although the occurrence of MAP is worldwide and has been documented in several African countries, the epidemiology and socioeconomic impacts remain undetermined and limited research information is available from the continent. At present, there are still significant knowledge gaps in all these areas as far as Africa is concerned. Due to the limited research on paratuberculosis in Africa, in spite of growing global concerns, it may rightfully be considered a neglected tropical disease with a potentially zoonotic role.

Mechanisms of inter-epidemic maintenance of Rift Valley fever phlebovirus

Rift Valley fever phlebovirus (RVFV) is an arthropod-borne virus that has caused substantial epidemics throughout Africa and in the Arabian Peninsula. The virus can cause severe disease in livestock and humans and therefore the control and prevention of viral outbreaks is of utmost importance. The epidemiology of RVFV has some particular characteristics. Unexpected and significant epidemics have been observed in spatially and temporally divergent patterns across the African continent. Sudden epidemics in previously unaffected areas are followed by periods of long-term apparent absence of virus and sudden, unpredictable reoccurrence in disparate regions. Therefore, the elucidation of underlying mechanisms of viral maintenance is one of the largest gaps in the knowledge of RVFV ecology. It remains unknown whether the virus needs to be reintroduced before RVF outbreaks can occur, or if unperceived viral circulation in local vertebrates or mosquitoes is sufficient for maintenance of the virus. To gain insight into these knowledge gaps, we here review existing data that describe potential mechanisms of RVFV maintenance, as well as molecular and serological studies in endemic and non-endemic areas that provide evidence of an inter- or pre-epidemic virus presence. Basic and country-specific mechanisms of RVFV introduction into non-endemic countries are summarized and an overview of studies using mathematical modeling of RVFV persistence is given.

Occurrence of antibodies anti -Toxoplasma gondii, Neospora caninum and Leptospira interrogans in a captive deer herd in Southern Brazil

Abstract A large number of Brazilian zoos keep many endangered species of deer, however, very few disease surveillance studies have been conducted among captive cervids. Blood samples from 32 Brazilian deer (Blastocerus dichotomus, Mazama nana and Mazama americana) kept in captivity at Bela Vista Biological Sanctuary (Foz do Iguaçu, Brazil) were investigated for 10 ruminant pathogens, with the aims of monitoring deer health status and evaluating any potential zoonotic risk. Deer serum samples were tested for Brucella abortus, Leptospira (23 serovars), Toxoplasma gondii, Neospora caninum, bovine viral diarrhea virus, infectious bovine rhinotracheitis virus, foot-and-mouth disease virus, western equine encephalitis virus, eastern equine encephalitis virus and Venezuelan equine encephalitis virus. Antibodies against T. gondii (15.6%), N. caninum (6.2%) and L. interrogans serogroup Serjoe (3.1%) were detected. The serological results for all other infectious agents were negative. The deer were considered to be clinically healthy and asymptomatic regarding any disease. Compared with studies on free-ranging deer, the prevalences of the same agents tested among the captive deer kept at the Sanctuary were lower, thus indicating good sanitary conditions and high-quality management practices at the zoo.

Seroprevalence and risk factors of Mycobacterium avium subspecies paratuberculosis infection in domestic sika deer in China

Paratuberculosis or Johne's disease (JD), caused by Mycobacterium avium subspecies paratuberculosis (MAP), is a chronic infectious granulomatous enteritis of ruminants and other animals, which has a worldwide occurrence, but little is known of MAP infection in domestic sika deer in Jilin Province, China. The objective of the present investigation was to examine seroprevalence and risk factors of MAP infection in Jilin Province. Serum samples collected from 1400 sika deer from 16 sika deer herds were collected in the 4 districts of the province between May 2013 and August 2014 and were tested independently for the presence of antibodies against MAP. A total of 247 (17.64 %) sika deer tested positive for MAP antibodies using a commercially available enzyme immunoassay kit. The management level of farm and collecting region of sika deer was the main risk factor associated with MAP infection. The present study revealed the seroprevalence of MAP infection in sika deer in Jilin Province, China, which provided the baseline data for taking comprehensive countermeasures and measures in effectively preventing and controlling MAP infection in sika deer.