Hyperparasitism in Ornithodoros erraticus

Helmy, Nadia; Khalil, Galila M.; Hoogstraal, Harry

doi:10.2307/3281305

Cited by 20 publications

(9 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In cases of high density of ticks or hyperparasitism in pig shelters, which is well documented in O . erraticus sensu stricto ticks [ 54 ] we can expect, based on the findings of this study, that infection rate and LVE by ticks can increase. The increase in the LVE in infected ticks over time stresses the importance of following current EU legislation guidelines for repopulation of pig shelters after six years of ASFV outbreaks [ 55 ].…”

Section: Discussionmentioning

confidence: 66%

Experimental Infection of Ornithodoros erraticus sensu stricto with Two Portuguese African Swine Fever Virus Strains. Study of Factors Involved in the Dynamics of Infection in Ticks

et al. 2015

View full text Add to dashboard Cite

African swine fever (ASF) is a frequently devastating hemorrhagic disease of domestic pigs and wild boar and Ornithodoros erraticus sensu stricto argasid ticks are the only biological vectors of African swine fever virus (ASFV) known to occur in Europe. Recently this disease emerged in Eastern Europe and Russian Federation, showing a huge potential for a rapid spread between countries. There is some risk of re-emergence of ASF in the countries where these ticks exist, that can contribute for the persistence of infection and compromise control measures. In this study we aimed to identify factors that determine the probability of infection and its dynamics in the tick vector Ornithodoros erraticus sensu stricto, with two Portuguese strains of ASFV. Our results suggest that these ticks have a high likelihood of excreting the two haemadsorbing ASF viruses of different host origins and that, in field surveys, the analysis of adults and 5th nymphal stage can provide the best chance of detecting virus infection. The results also indicate that infection of pigs with highly virulent ASF viruses will promote higher rates of infection and a higher likelihood for virus excretion by ticks. Nevertheless, there is also a risk, although lower, that ticks can become infected on pigs that have overcome the acute phase of infection, which was simulated in our study by membrane feeding ticks with low titres of virus. We believe these results can be valuable in designing and interpreting the results of ASF control programmes, and future work can also be undertaken as our dataset is released under open access, to perform studies in risk assessment for ASFV persistence in a region where O. erraticus sensu stricto ticks are present.

show abstract

Section: Discussionmentioning

confidence: 66%

Experimental Infection of Ornithodoros erraticus sensu stricto with Two Portuguese African Swine Fever Virus Strains. Study of Factors Involved in the Dynamics of Infection in Ticks

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Bhat (1969) observed that male O. tholozani would not feed on rabbits but readily fed on engorged nymphs and females, however numbers of observations were not given. Helmy et al (1983) subsequently studied this behavior in O. erraticus , and as we observed for O. hermsi , O. erraticus males hyperparasitized other ticks far more frequently than did females and nymphs. Additionally, these investigators followed individual nymphs through the molt to determine whether they developed into males (designated N-♂) or females (designated N-♀).…”

Section: Discussionmentioning

confidence: 59%

“…In ticks, hyperparasitism is conspecific, with ticks feeding upon other ticks of the same species. Cases of conspecific hyperparasitism (herein referred to as hyperparasitism) have been documented for many species of argasid (soft) ticks, including Ornithodoros puertoricensis , Ornithodoros erraticus , Ornithodoros tartakovskyi , Ornithodoros tholozani, Ornithodoros turicata, Ornithodoros parkeri , a few Argas species, as well as the ixodid (hard) ticks Amblyomma rotundatum, Rhipicephalus (Boophilus) annulatus, Hyalomma detritum and several species of Ixodes (Nuttall and Warburton, 1911; Klyushkina, 1956; Uzakov, 1961; Moorhouse, 1966; Bhat, 1969; Moorhouse and Heath, 1975; Londono, 1976; Helmy et al, 1983; Endris et al, 1991; Labruna et al, 2007). In most cases, the hyperparasitism was a single documented case.…”

Section: Introductionmentioning

confidence: 99%

“…In most cases, the hyperparasitism was a single documented case. However, one study focused specifically on hyperparasitism in a laboratory colony of O. erraticus (Helmy et al, 1983). The authors observed a high frequency of hyperparasitism in specific tick stages, and the spirochete Borrelia crocidurae was acquired and transmitted between ticks when feeding on each other.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Conspecific hyperparasitism: An alternative route for Borrelia hermsii transmission by the tick Ornithodoros hermsi

Williamson

Schwan

2018

Ticks and Tick-borne Diseases

View full text Add to dashboard Cite

Ixodid and argasid ticks may hyperparasitize other individuals of their own species to acquire a blood meal, however most accounts are based on single observations and the behavior has rarely been studied. While maintaining laboratory colonies of Ornithodoros species, we noticed that unfed ticks occasionally fed on other ticks that were feeding on mice, and unfed ticks parasitized engorged ticks when confined together in tubes. Therefore, we investigated hyperparasitism by Ornithodoros hermsi and the ability of these ticks to acquire and transmit the relapsing fever spirochete Borrelia hermsii when feeding on other ticks. Various combinations of unfed and recently engorged male, female and nymphal ticks were confined for 1-2h as individual pairs or in groups, then examined to determine the number of ticks that acquired blood by feeding on others. Unfed O. hermsi males were far more likely to hyperparasitize other ticks than were females and nymphs, as 78.6% of males (114 of 145 ticks) fed when confined with recently engorged ticks. Unfed females and nymphs also hyperparasitized other ticks but far less frequently (only 6.7% combined; 17 of 254 ticks). Infection experiments demonstrated that unfed males acquired B. hermsii when parasitizing nymphs that had recently engorged on a spirochetemic mouse, and unfed infected males transmitted spirochetes to recently engorged nymphs. Some ticks infected via hyperparasitism subsequently transmitted B. hermsii to mice. Hyperparasitism by O. hermsi occurred more frequently than expected, although possibly influenced by our experimental design. The significance of this behavior as it may influence the horizontal transfer of B. hermsii in nature is not known but worthy of future consideration.

show abstract

“…Conspecific hyperparasitism may contribute to the spread of pathogens within a tick population in natural conditions. This is suggested by the results of previous laboratory investigations confirming transmission of Dipetalonema viteae in Ornithodorus tartakovskyi [51], Borrelia crocidurae in Ornithodoros erraticus [52], and Borrelia burgdoreri s.l. spirochetes in Ixodes persulcatus [33].…”

Section: Resultsmentioning

confidence: 64%

Conspecific hyperparasitism in the <i>Hyalomma excavatum</i> tick and considerations on the biological and epidemiological implications of this phenomenon

Buczek

Bartosik

Buczek

et al. 2019

Ann Agric Environ Med.

View full text Add to dashboard Cite

Objective. This study presents for the first time a case of Hyalomma excavatum hyperparasitism and an analysis of this phenomenon in terms of its potential role in the biology of ticks and epidemiology of tick-borne diseases. Materials and method. Two partially engorged H. excavatum females, one fully engorged female, and 5 males were collected from a naïve rabbit and placed together in a rearing chamber at a temperature of 25 °C and 75% humidity. Results. 3-4 days after tick detachment from the host's skin, one partially engorged H. excavatum female was observed attached to the idiosoma of the fully engorged conspecific female. Conclusions. This study and observations of other authors confirm that partially engorged ixodid ticks can re-infest the host, and even co-feeding fully engorged ticks in order to collect the blood meal that is indispensable for important physiological processes. However, inefficient feeding of a partially engorged female on another conspecific female may reduce its reproductive performance and disturb the development of eggs and larvae. It seems that parasitism of a tick on another conspecific specimen, when at least one of them is infected by a microorganism, may be a yet poorly explored route of transmission of pathogens or symbionts between the ticks. Initiation of feeding by a hungry or partially engorged tick on a fully engorged specimen is an attempt to obtain food in the drastic conditions of the absence of a target host. Tick hyperparasitism with concurrent pathogen transmission can contribute to the genospecific diversity of pathogens in vectors and hosts.

show abstract

Hyperparasitism in Ornithodoros erraticus

Cited by 20 publications

References 6 publications

Experimental Infection of Ornithodoros erraticus sensu stricto with Two Portuguese African Swine Fever Virus Strains. Study of Factors Involved in the Dynamics of Infection in Ticks

Experimental Infection of Ornithodoros erraticus sensu stricto with Two Portuguese African Swine Fever Virus Strains. Study of Factors Involved in the Dynamics of Infection in Ticks

Conspecific hyperparasitism: An alternative route for Borrelia hermsii transmission by the tick Ornithodoros hermsi

Conspecific hyperparasitism in the <i>Hyalomma excavatum</i> tick and considerations on the biological and epidemiological implications of this phenomenon

Contact Info

Product

Resources

About