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Mite allergens
Published in Richard F. Lockey, Dennis K. Ledford, Allergens and Allergen Immunotherapy, 2020
Enrique Fernández-Caldas, Leonardo Puerta, Luis Caraballo, Victor Iraola, Richard F. Lockey
Ticks (Ixodida), belonging to the families Ixodidae and Argasidae, have several proteins in their saliva that can induce IgE-mediated reactions after a bite. Several cases of anaphylaxis after tick bites are reported [187]. The allergenic composition of these mites has been analyzed [188], and an important allergen of Argas reflexus, the European pigeon tick, is cloned. Arg r 1 is a protein belonging to the lipocalin family [189]. In the case of the paralysis tick, Ixodes holocyclus, an allergen of 28 kDa from the salivary gland, has been identified [190]. Other allergenic proteins, with molecular masses of 51, 38, and 35 kDa from I. pacificus, I. ricinus, Haemaphysalis punctata, and Rhipicephalus sp. are described [191–194].
Ticks
Published in Gail Miriam Moraru, Jerome Goddard, The Goddard Guide to Arthropods of Medical Importance, Seventh Edition, 2019
Gail Miriam Moraru, Jerome Goddard
There are three families of ticks recognized today: (1) Ixodidae (hard ticks), (2) Argasidae (soft ticks), and (3) Nuttalliellidae (a small, curious, little-known family represented by a single species that possesses some characteristics of both hard and soft ticks). The terms hard and soft refer to the presence in the Ixodidae of a dorsal scutum or “plate” that is absent in the Argasidae.
Clinical Toxicology of Tick Bites
Published in Jürg Meier, Julian White, Handbook of: Clinical Toxicology of Animal Venoms and Poisons, 2017
Ticks are invertebrates, members of the class Arachnida, subclass Acari, order Meostigmata. They have 4 pairs of walking legs and no antennae, a feeding device (hypostoma) and are all ectoparasites of terrestrial vertebrates, particularly mammals. Ticks of medical importance are found in two distinct families; Ixodidae (hard ticks) and Argasidae (soft ticks). The Ixodid ticks are in the majority (at least 644 species2). They have a hard body plate, or cuticle, unlike the Argasid ticks (at least 149 species2), the cuticle of which is not rigid, and “leathery”. Argasid ticks feed, then drop off the host, the feeding process often taking only 5 to 25 mins. In contrast, Ixodid ticks in the adult phase (females) may remain attached to the host, feeding, for a considerably longer period of time, up to 11 days, possibly more. In general, it appears that the longer the period of attachment, the more likely is paralysis. Tick paralysis is a phenomenon associated with Ixodid ticks, and the following description of feeding biology relates to this group.
Additional considerations for anti-tick vaccine research
Published in Expert Review of Vaccines, 2022
José de la Fuente, Marinela Contreras
Recent publications and particularly a recent paper by Ndawula, Jr [1]. provided a comprehensive review on anti-tick vaccine research and results. In this review, the author addressed the limitations in tick vaccine research with emphasis on the methodology for the evaluation of vaccine efficacy and effectiveness and the need to advance in the characterization of the immunological mechanisms mediating vaccine efficacy for the control of both ixodid and argasid tick infestations. We agree on this proposal for the evaluation of vaccine efficacy and effectiveness. However, additional considerations disclosed here using our research based on the Subolesin tick antigen model are relevant for the development of effective and safe vaccines for the control of tick infestations and tick-borne diseases (TBD).
Post-exposure prophylactic vaccine candidates for the treatment of human Risk Group 4 pathogen infections
Published in Expert Review of Vaccines, 2020
James Logue, Ian Crozier, Peter B Jahrling, Jens H Kuhn
Finally, tick-borne encephalitis virus (TBEV; Flaviviridae: Flavivirus) is generally transmitted by ixodid ticks in Western (Ixodes ricinus) and Eastern (Ixodes persulcatus) Europe. The virus is maintained by over 100 species of wild animals, including voles, deer, and domestic animals such as sheep [122–124]. Although patients infected with TBEV normally only present with an initial, nonspecific febrile phase, 20–30% of patients progress to a second stage of disease with CNS signs (meningitis, encephalitis, or both). Lethality is generally 1–2%, but 30–60% of patients develop chronic neuropsychiatric sequelae [125,126]. Three different vaccines for pre-exposure disease prevention (IPVE, FSME-IMMUN, and Encepur) are generally available in endemic regions [127]. However, fears over the potential of antibody-dependent disease enhancement or increased viral infectivity caused by ‘sub-optimal’ concentrations of virus-specific antibodies have hampered further vaccine development [128]. For this reason and the potential of other adverse effects [129], none of these vaccines are licensed by the US FDA. Vaccine use is neither recommended by the US Centers for Disease Control and Prevention (CDC) nor the WHO except for high-risk individuals, such as laboratory workers or workers with high exposure to potentially infected host ticks [130,131]. Multiple studies into the use of antibody treatments as PEP have produced promising results in laboratory mice with no disease enhancement [132,133].
Global meta-analysis on Babesia infections in human population: prevalence, distribution and species diversity
Published in Pathogens and Global Health, 2022
Solomon Ngutor Karshima, Magdalene Nguvan Karshima, Musa Isiyaku Ahmed
Babesia species have distinct geographic distributions. Transmission primarily occurs through bites of ticks of the family Ixodidae particularly those of the genus Ixodes. However, transfusion-associated [4,5] and vertical transmission from mothers to infants particularly for B. microti [6,7] are well documented. Quarter to half of infections are usually asymptomatic; usually confused with malaria due to nonspecific symptoms like fever and hemolytic anemia [8]. In immunocompromised population, these parasites infect host’s erythrocytes causing hemolytic anemia, intravascular coagulopathy, hepatomegaly and splenomegaly; leading to complications such as respiratory distress syndrome, heart failure, inflammation of the central nervous system and death [8].