scholarly journals Can Bats Serve as Reservoirs for Arboviruses?

Viruses ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 215 ◽  
Author(s):  
Anna C. Fagre ◽  
Rebekah C. Kading

Bats are known to harbor and transmit many emerging and re-emerging viruses, many of which are extremely pathogenic in humans but do not cause overt pathology in their bat reservoir hosts: henipaviruses (Nipah and Hendra), filoviruses (Ebola and Marburg), and coronaviruses (SARS-CoV and MERS-CoV). Direct transmission cycles are often implicated in these outbreaks, with virus shed in bat feces, urine, and saliva. An additional mode of virus transmission between bats and humans requiring further exploration is the spread of disease via arthropod vectors. Despite the shared ecological niches that bats fill with many hematophagous arthropods (e.g. mosquitoes, ticks, biting midges, etc.) known to play a role in the transmission of medically important arboviruses, knowledge surrounding the potential for bats to act as reservoirs for arboviruses is limited. To this end, a comprehensive literature review was undertaken examining the current understanding and potential for bats to act as reservoirs for viruses transmitted by blood-feeding arthropods. Serosurveillance and viral isolation from either free-ranging or captive bats are described in relation to four arboviral groups (Bunyavirales, Flaviviridae, Reoviridae, Togaviridae). Further, ecological associations between bats and hematophagous viral vectors are characterized (e.g. bat bloodmeals in mosquitoes, ingestion of mosquitoes by bats, etc). Lastly, knowledge gaps related to hematophagous ectoparasites (bat bugs and bed bugs (Cimicidae) and bat flies (Nycteribiidae and Streblidae)), in addition to future directions for characterization of bat-vector-virus relationships are described.

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S312-S312
Author(s):  
Seth D Judson ◽  
Vincent J Munster

Abstract Background During the pandemic of coronavirus disease 2019 (COVID-19), many questions arose regarding risks for hospital-acquired or nosocomial transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Aerosol generating medical procedures (AGMPs), techniques that can generate infectious, virus-laden aerosols, could potentially amplify transmission among healthcare workers (HCWs). Thus, it was widely recommended that HCWs use airborne precautions when performing AGMPs. However, in clinical settings it is often unclear what procedures constitute AGMPs and how the risk varies by procedure or pathogen. We set out to further define AGMPs and assess the risk for nosocomial transmission of SARS-CoV-2 and other high-risk viruses via AGMPs. Methods We identified potential AGMPs and emerging viruses that were high-risk for nosocomial transmission through reviewing experimental and clinical data. Potential AGMPs were those associated with previous virus transmission or mechanically capable of transmission. High-risk viruses were defined as those that cause severe disease in humans for which limited therapies or interventions exist, are infectious via aerosols in humans or non-human primates (NHPs), found in the respiratory tract of infected humans or NHPs, and had previous evidence of nosocomial transmission. Results We identified multiple potential AGMPs, which could be divided into those that generate aerosols or induce a patient to form aerosols, as well as eight families of high-risk viruses. All of the viruses were emerging zoonotic RNA viruses. In the family Coronaviridae, we identified potential evidence for SARS-CoV-1, MERS-CoV, and SARS-CoV-2 transmission via AGMPs. SARS-CoV-1 and SARS-CoV-2 were also found to be similarly stable when aerosolized. Conclusion Multiple emerging zoonotic viruses pose a high risk for nosocomial transmission through a variety of AGMPs. Given the similar stability of SARS-CoV-2 with SARS-CoV-1 when aerosolized and prior nosocomial transmission of SARS-CoV-1 via AGMPs, we suspect that certain AGMPs pose an increased risk for SARS-CoV-2 transmission. Additional experimental studies and on-site clinical sampling during AGMPs are necessary to further risk stratify AGMPs. Disclosures All Authors: No reported disclosures


2021 ◽  
Vol 219 (2) ◽  
Author(s):  
Elizabeth J. Fay ◽  
Keir M. Balla ◽  
Shanley N. Roach ◽  
Frances K. Shepherd ◽  
Dira S. Putri ◽  
...  

Emerging viruses threaten global health, but few experimental models can characterize the virus and host factors necessary for within- and cross-species transmission. Here, we leverage a model whereby pet store mice or rats—which harbor natural rodent pathogens—are cohoused with laboratory mice. This “dirty” mouse model offers a platform for studying acute transmission of viruses between and within hosts via natural mechanisms. We identified numerous viruses and other microbial species that transmit to cohoused mice, including prospective new members of the Coronaviridae, Astroviridae, Picornaviridae, and Narnaviridae families, and uncovered pathogen interactions that promote or prevent virus transmission. We also evaluated transmission dynamics of murine astroviruses during transmission and spread within a new host. Finally, by cohousing our laboratory mice with the bedding of pet store rats, we identified cross-species transmission of a rat astrovirus. Overall, this model system allows for the analysis of transmission of natural rodent viruses and is a platform to further characterize barriers to zoonosis.


FACETS ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 105-110 ◽  
Author(s):  
Benoit Talbot ◽  
Nusha Keyghobadi ◽  
Brock Fenton

Cimicid insects, bed bugs and their allies, include about 100 species of blood-feeding ectoparasites. Among them, a few have become widespread and abundant pests of humans. Cimicids vary in their degree of specialization to hosts. Whereas most species specialize on insectivorous birds or bats, the common bed bug can feed on a range of distantly related host species, such as bats, humans, and chickens. We suggest that association with humans and generalism in bed bugs led to fundamentally different living conditions that fostered rapid growth and expansion of their populations. We propose that the evolutionary and ecological success of common bed bugs reflected exploitation of large homeothermic hosts (humans) that sheltered in buildings. This was a departure from congeners whose hosts are much smaller and often heterothermic. We argue that interesting insights into the biology of pest species may be obtained using an integrated view of their ecology and evolution.


2018 ◽  
Vol 18 (5) ◽  
pp. 258-265 ◽  
Author(s):  
Alexandra E. Moskaluk ◽  
Matthew J. Stuckey ◽  
David A. Jaffe ◽  
Rickie W. Kasten ◽  
Alvaro Aguilar-Setién ◽  
...  

Pathogens ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 72
Author(s):  
Jan Slingenbergh

The current classification of animal viruses is largely based on the virus molecular world. Less attention is given to why and how virus fitness results from the success of virus transmission. Virus transmission reflects the infection-shedding-transmission dynamics, and with it, the organ system involvement and other, macroscopic dimensions of the host environment. This study describes the transmission ecology of the world main livestock viruses, 36 in total, a mix of RNA, DNA and retroviruses. Following an iterative process, the viruses are virtually ranked in an outer- to inner-body fashion, by organ system, on ecological grounds. Also portrayed are the shifts in virus host tropism and virus genome. The synthesis of the findings reveals a predictive virus evolution framework, based on the outer- to inner-body changes in the interplay of host environment-transmission modes-organ system involvement-host cell infection cycle-virus genome. Outer-body viruses opportunistically respond to the variation in the external environment. For example, respiratory and enteric viruses tend to be associated with poultry and pig mass rearing. Ruminant and equine viruses tend to be more deep-rooted and host-specific, and also establish themselves in the vital inner-body systems. It is concluded that the framework may assist the study of new emerging viruses and pandemic risks.


2019 ◽  
Vol 72 (1) ◽  
Author(s):  
Áine B. Collins ◽  
Michael L. Doherty ◽  
Damien J. Barrett ◽  
John F. Mee

Abstract In Autumn 2011, nonspecific clinical signs of pyrexia, diarrhoea, and drop in milk yield were observed in dairy cattle near the German town of Schmallenberg at the Dutch/German border. Targeted veterinary diagnostic investigations for classical endemic and emerging viruses could not identify a causal agent. Blood samples were collected from animals with clinical signs and subjected to metagenomic analysis; a novel orthobunyavirus was identified and named Schmallenberg virus (SBV). In late 2011/early 2012, an epidemic of abortions and congenital malformations in calves, lambs and goat kids, characterised by arthrogryposis and hydranencephaly were reported in continental Europe. Subsequently, SBV RNA was confirmed in both aborted and congenitally malformed foetuses and also in Culicoides species biting midges. It soon became evident that SBV was an arthropod-borne teratogenic virus affecting domestic ruminants. SBV rapidly achieved a pan-European distribution with most countries confirming SBV infection within a year or two of the initial emergence. The first Irish case of SBV was confirmed in the south of the country in late 2012 in a bovine foetus. Since SBV was first identified in 2011, a considerable body of scientific research has been conducted internationally describing this novel emerging virus. The aim of this systematic review is to provide a comprehensive synopsis of the most up-to-date scientific literature regarding the origin of SBV and the spread of the Schmallenberg epidemic, in addition to describing the species affected, clinical signs, pathogenesis, transmission, risk factors, impact, diagnostics, surveillance methods and control measures. This review also highlights current knowledge gaps in the scientific literature regarding SBV, most notably the requirement for further research to determine if, and to what extent, SBV circulation occurred in Europe and internationally during 2017 and 2018. Moreover, recommendations are also made regarding future arbovirus surveillance in Europe, specifically the establishment of a European-wide sentinel herd surveillance program, which incorporates bovine serology and Culicoides entomology and virology studies, at national and international level to monitor for the emergence and re-emergence of arboviruses such as SBV, bluetongue virus and other novel Culicoides-borne arboviruses.


Viruses ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1441
Author(s):  
Alexander Bergman ◽  
Emma Dahl ◽  
Åke Lundkvist ◽  
Jenny C. Hesson

A crucial, but unresolved question concerning mosquito-borne virus transmission is how these viruses can remain endemic in regions where the transmission is halted for long periods of time, due to mosquito inactivity in, e.g., winter. In northern Europe, Sindbis virus (SINV) (genus alphavirus, Togaviridae) is transmitted among birds by Culex mosquitoes during the summer, with occasional symptomatic infections occurring in humans. In winter 2018–19, we sampled hibernating Culex spp females in a SINV endemic region in Sweden and assessed them individually for SINV infection status, blood-feeding status, and species. The results showed that 35 out of the 767 collected mosquitoes were infected by SINV, i.e., an infection rate of 4.6%. The vast majority of the collected mosquitoes had not previously blood-fed (98.4%) and were of the species Cx. pipiens (99.5%). This is the first study of SINV overwintering, and it concludes that SINV can be commonly found in the hibernating Cx. pipiens population in an endemic region in Sweden, and that these mosquitoes become infected through other means besides blood-feeding. Further studies on mosquito ecology and viral interactions are needed to elucidate the mechanisms of the persistence of these viruses over winter.


Author(s):  
Lin Liu ◽  
Qin Shen ◽  
Nan Li ◽  
Yuwen He ◽  
Na Han ◽  
...  

Abstract The genus Culicoides includes biting midges, some of which are vectors for viruses that cause diseases in humans and animals. Knowledge of the roles of Culicoides in viral ecology is inadequate. We collected ~300 000 samples of Culicoides and mosquitoes in 15 representative regions within Yunnan, China. Using mosquitoes as reference vectors, we designed a comparative virome strategy to study the viral composition, diversity, hosts and spatiotemporal distribution of Culicoides. A map of viromes in Culicoides and mosquitoes in Yunan province, China, was constructed. At the same locations, Culicoides and mosquitoes usually share a similar viral diversity. At least 10 important pathogenic viruses were detected from Culicoides. Many novel viruses were discovered, including 21 segmented viruses of Flaviviridae, 180 viruses of Monjiviricetes and 130 viruses of Bunyavirales. The findings demonstrate that Culicoides is an important part of viral ecology and should be studied and monitored for potentially emerging viruses.


2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Michael L. Fisher ◽  
Jay F. Levine ◽  
James S. Guy ◽  
Hiroyuki Mochizuki ◽  
Matthew Breen ◽  
...  

Abstract Background The common bed bug, Cimex lectularius, is an obligatory blood-feeding ectoparasite that requires a blood meal to molt and produce eggs. Their frequent biting to obtain blood meals and intimate association with humans increase the potential for disease transmission. However, despite more than 100 years of inquiry into bed bugs as potential disease vectors, they still have not been conclusively linked to any pathogen or disease. This ecological niche is extraordinarily rare, given that nearly every other blood-feeding arthropod is associated with some type of human or zoonotic disease. Bed bugs rely on the bacteria Wolbachia as an obligate endosymbiont to biosynthesize B vitamins, since they acquire a nutritionally deficient diet, but it is unknown if Wolbachia confers additional benefits to its bed bug host. In some insects, Wolbachia induces resistance to viruses such as Dengue, Chikungunya, West Nile, Drosophila C and Zika, and primes the insect immune system in other blood-feeding insects. Wolbachia might have evolved a similar role in its mutualistic association with the bed bug. In this study, we evaluated the influence of Wolbachia on virus replication within C. lectularius. Methods We used feline calicivirus as a model pathogen. We fed 40 bed bugs from an established line of Wolbachia-cured and a line of Wolbachia-positive C. lectularius a virus-laden blood meal, and quantified the amount of virus over five time intervals post-feeding. The antibiotic rifampicin was used to cure bed bugs of Wolbachia. Results There was a significant effect of time post-feeding, as the amount of virus declined by ~90% over 10 days in both groups, but no significant difference in virus titer was observed between the Wolbachia-positive and Wolbachia-cured groups. Conclusions These findings suggest that other mechanisms are involved in virus suppression within bed bugs, independent of the influence of Wolbachia, and our conclusions underscore the need for future research.


1985 ◽  
Vol 117 (8) ◽  
pp. 995-1006 ◽  
Author(s):  
John W. McCreadie ◽  
Murray H. Colbo ◽  
Gordon F. Bennett

AbstractA cattle-baited (C-B) trap and a Trueman–McIver (T-M) segregating CO2 trap provided information on seasonal abundance, host-seeking activity, and blood-feeding of biting-flies near St. John's, Newfoundland. A total of 19 682 biting-flies (26 species) were collected (C-B trap = 11 407; T-M trap = 8275) from 26 May to 16 September 1982. Black-flies (Simuliidae) comprised 94.1% of the total sample (C-B trap = 10 747; T-M trap = 7773). Mosquitoes (Culicidae), biting midges (Ceratopogonidae), and tabanids (Tabanidae) comprised the remainder. Blood-fed flies represented 54.7% of the total catch in the C-B trap, but the proportion varied considerably among species. Black-fly activity was concentrated in June and July, though flies were also collected in May, August, and September. Prosimulium mixtum was the predominant species in June and Simulium venustum/verecundum complex was the major pest in July. Prosimulium mixtum was most active from mid-morning to late-afternoon, with little evening activity. Simulium venustum/verecundum complex showed 2 peaks of activity, one in the morning and another in the early evening. A few P. mixtum and S. venustum/verecundum complex were active after dark. Captures from the T-M and C-B traps were compared to test the reliability of the T-M trap as an indicator of activity of biting-flies attracted to cattle. Significant correlations (P < 0.001) between the number of flies collected in the 2 traps were found for P. mixtum and S. venustum/verecundum complex. Remaining species were taken in numbers too low for analysis.


Sign in / Sign up

Export Citation Format

Share Document