Diapause in Tick Vectors of Disease

Author(s):  
Daniel E. Sonenshine
Keyword(s):  
Author(s):  
Matthew T Milholland ◽  
Lars Eisen ◽  
Robyn M Nadolny ◽  
Andrias Hojgaard ◽  
Erika T Machtinger ◽  
...  

Abstract Lyme and other tick-borne diseases are increasing in the eastern United States and there is a lack of research on integrated strategies to control tick vectors. Here we present results of a study on tick-borne pathogens detected from tick vectors and rodent reservoirs from an ongoing 5-yr tick suppression study in the Lyme disease-endemic state of Maryland, where human-biting tick species, including Ixodes scapularis Say (Acari: Ixodidae) (the primary vector of Lyme disease spirochetes), are abundant. During the 2017 tick season, we collected 207 questing ticks and 602 ticks recovered from 327 mice (Peromyscus spp. (Rodentia: Cricetidae)), together with blood and ear tissue from the mice, at seven suburban parks in Howard County. Ticks were selectively tested for the presence of the causative agents of Lyme disease (Borrelia burgdorferi sensu lato [s.l.]), anaplasmosis (Anaplasma phagocytophilum), babesiosis (Babesia microti), ehrlichiosis (Ehrlichia ewingii, Ehrlichia chaffeensis, and ‘Panola Mountain’ Ehrlichia) and spotted fever group rickettsiosis (Rickettsia spp.). Peromyscus ear tissue and blood samples were tested for Bo. burgdorferi sensu stricto (s.s), A. phagocytophilum, Ba. microti, and Borrelia miyamotoi. We found 13.6% (15/110) of questing I. scapularis nymphs to be Bo. burgdorferi s.l. positive and 1.8% (2/110) were A. phagocytophilum positive among all sites. Borrelia burgdorferi s.s. was found in 71.1% (54/76) of I. scapularis nymphs removed from mice and 58.8% (194/330) of captured mice. Results from study on tick abundance and pathogen infection status in questing ticks, rodent reservoirs, and ticks feeding on Peromyscus spp. will aid efficacy evaluation of the integrated tick management measures being implemented.


1991 ◽  
Vol 106 (2) ◽  
pp. 373-382 ◽  
Author(s):  
A. J. Shepherd ◽  
R. Swanepoel ◽  
S. P. Shepherd ◽  
P. A. Leman ◽  
O. Mathee

SUMMARYIn order to determine the way in which vertebrates infected with Crimean-Congo haemorrhagic fever (CCHF) virus and potential ixodid tick vectors interact in nature, immature and adult ticks of several species were fed on viraemic mammals and then assayed for virus content at varying times after feeding. CCHF virus was not isolated from ticks of six species tested after feeding as adults and immature forms on sheep with viraemia of 102·5−3·2LD 50/ml, nor from larval ticks fed on guinea-pigs and white-tailed rats with viraemia of 101·9−2·7LD 50/ml. In contrast, virus was isolated from 10 of 152 pools of engorged adult ticks of 5 species that fed on cattle with viraemia of 101·5−2·7LD 50/ml and from 3 of 137 female ticks after oviposition. Infection was transmitted to larval and nymphalHyalomma truncatumandH. marginatum rufipes, but not toRhipicephalus evertsi evertsi, from a scrub hare with viraemia of 104·250/ml but only nymphalH. truncatumandH. m. rufipesbecame infected from scrub hares with viraemia of 102·6−2·7LD 50/ml. Infection was transmitted trans-stadially inH. m. rufipesandH. truncatuminfected as nymphae, and adultH. m. rufipestransmitted infection to a sheep. No evidence of transovarial transmission was found in larval progeny of ticks exposed to CCHF virus as adults on sheep and cattle or as immatures on scrub hares.


2013 ◽  
Vol 112 (8) ◽  
pp. 3013-3017 ◽  
Author(s):  
Rafael Antonio Nascimento Ramos ◽  
Alessio Giannelli ◽  
Emanuele Brianti ◽  
Giada Annoscia ◽  
Cinzia Cantacessi ◽  
...  

2018 ◽  
Vol 184 (3) ◽  
pp. 95-95 ◽  
Author(s):  
Robert M Coultous ◽  
Paul Phipps ◽  
Charlie Dalley ◽  
Jane Lewis ◽  
Toni-Ann Hammond ◽  
...  

Equine piroplasmosis (EP) has historically been of minor concern to UK equine practitioners, primarily due to a lack of competent tick vectors. However, increased detection of EP tick vector species in the UK has been reported recently. EP screening is not currently required for equine importation, and when combined with recent relaxations in movement regulations, there is an increased risk regarding disease incursion and establishment into the UK. This study evaluated the prevalence of EP by both serology and PCR among 1242 UK equine samples submitted for EP screening between February and December 2016 to the Animal and Plant Health Agency and the Animal Health Trust. Where information was available, 81.5 per cent of submissions were for the purpose of UK export testing, and less than 0.1 per cent for UK importation. Serological prevalence of EP was 8.0 per cent, and parasite DNA was found in 0.8 per cent of samples. A subsequent analysis of PCR sensitivity in archived clinical samples indicated that the proportion of PCR-positive animals is likely to be considerably higher. The authors conclude that the current threat imposed by UK carrier horses is not adequately monitored and further measures are required to improve national biosecurity and prevent endemic disease.


2021 ◽  
Author(s):  
Erin M Stayton ◽  
Megan Lineberry ◽  
Jennifer Thomas ◽  
Tina Bass ◽  
Kelly Allen ◽  
...  

Abstract Background: Babesia species are intraerythrocytic Apicomplexan parasites that infect a wide range of vertebrate hosts. These pathogens are typically transmitted either by tick vectors or by direct blood-to-blood contact, and may cause life-threatening clinical disease such as thrombocytopenia, hemolytic anemia, and acute renal failure in canine hosts. While Babesia vogeli and Babesia gibsoni infections have both been reported in Oklahoma, reports of B. conradae infections have been limited to California. Methods: Whole blood samples were collected in EDTA tubes from all dogs in four separate kennels in Oklahoma. DNA was extracted from each blood sample and a nested PCR was performed using general Apicomplexan primers for the partial 18S rRNA gene. PCR products were electrophoresed in agarose matrix and appropriately sized amplicons were sequenced. Sequences were compared to reference 18S rRNA sequences available in GenBank, and samples with >98% homology to B. conradae (GenBank MK256976) were considered positive. B. conradae positive dogs were then treated with atovaquone (13.5 mg/kg TID) and azithromycin (10 mg/kg SID) for 10 days and retested at 30 and 60 days post treatment by PCR. Results: Fifteen of 40 dogs tested positive for B. conradae with 98–100% sequence homology to B. conradae from California. All positive cases were coyote-hunting Greyhounds. Treatment of clinically ill dogs with atovaquone and azithromycin resulted in complete clinical recovery in clinically ill dogs and all treated dogs had negative follow-up PCR at 30 and 60 days post treatment. Conclusions: Collectively, this study (i) documents the occurrence of B. conradae in Oklahoma, (ii) highlights this pathogen as a differential to be considered when clinical signs are present, and (iii) supports the use of atovaquone and azithromycin as effective treatment in these cases.


2020 ◽  
Author(s):  
Danielle M. Tufts ◽  
Laura B. Goodman ◽  
Meghan C. Benedict ◽  
April D. Davis ◽  
Meredith C. VanAcker ◽  
...  

AbstractHaemaphysalis longicornis, the Asian longhorned tick, is an invasive ixodid tick that has rapidly spread across the northeastern and southeastern regions of the United States since first reported in 2017. The emergence of H. longicornis presents a potential threat for livestock, wildlife, and human health as the host associations and vector potential of this invasive pest in the United States are poorly understood. Previous field data from the United States has shown that H. longicornis was not associated with natural populations of small mammals or birds, but they show a preference for medium sized mammals in laboratory experiments. Therefore, medium and large sized mammals were sampled on Staten Island, New York to determine H. longicornis host associations and vector potential for a range of human and veterinary pathogens. A total of 97 hosts were sampled and five species of tick (Amblyomma americanum, Dermacentor variabilis, H. longicornis, Ixodes scapularis, Ixodes cookei) were found feeding concurrently on these hosts. Haemaphysalis longicornis was found in the highest proportions compared to other native tick species on raccoons (55.4%), Virginia opossums (28.9%), and white-tailed deer (11.5%). Tissue, blood, and engorged larvae were tested for 17 different pathogens using a nanoscale PCR platform. Infection with five pathogens (Borrelia burgdorferi, Anaplasma phagocytophilum, Rickettsia spp., Mycoplasma haemocanis, and Bartonella spp.) was detected in host samples, but no pathogens were found in any larval samples. These results suggest that although large and medium sized mammals feed large numbers of H. longicornis ticks in the environment there is presently a low potential for H. longicornis to acquire pathogens from these wildlife hosts.HighlightsH. longicornis were sampled from seven genera of large and medium-sized mammalsRaccoons, opossums, and white-tailed deer fed a large proportion of H. longicornisH. longicornis did not acquire pathogens through co-feeding with native tick vectorsHost species were infected with a range of pathogens of human and veterinary concernHost-derived H. longicornis engorged larvae were not infected with any pathogens


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Camille Victoire Migné ◽  
Vaclav Hönig ◽  
Sarah Irène Bonnet ◽  
Martin Palus ◽  
Sabine Rakotobe ◽  
...  

AbstractUp to 170 tick-borne viruses (TBVs) have been identified to date. However, there is a paucity of information regarding TBVs and their interaction with respective vectors, limiting the development of new effective and urgently needed control methods. To overcome this gap of knowledge, it is essential to reproduce transmission cycles under controlled laboratory conditions. In this study we assessed an artificial feeding system (AFS) and an immersion technique (IT) to infect Ixodes ricinus ticks with tick-borne encephalitis (TBE) and Kemerovo (KEM) virus, both known to be transmitted predominantly by ixodid ticks. Both methods permitted TBEV acquisition by ticks and we further confirmed virus trans-stadial transmission and onward transmission to a vertebrate host. However, only artificial feeding system allowed to demonstrate both acquisition by ticks and trans-stadial transmission for KEMV. Yet we did not observe transmission of KEMV to mice (IFNAR−/− or BALB/c). Artificial infection methods of ticks are important tools to study tick-virus interactions. When optimally used under laboratory settings, they provide important insights into tick-borne virus transmission cycles.


2021 ◽  
pp. 492-499
Author(s):  
Hao Li ◽  
Li-Qun Fang ◽  
Wei Liu

Abstract This expert opinion provides an overview of the type and distribution of tick species and emerging tick-borne pathogens in tick vectors and human beings (such as Anaplasma, Babesia, spotted fever group rickettsiae, Borrelia and viruses) in China and considers the potential influence of global warming and climate change.


Sign in / Sign up

Export Citation Format

Share Document