Acarina (2004) 12, 121-139
A.N. Alekseev and H.V. Dubinina (2004)
[Eurasian Ixodes tick genotypes, their properties and vector capacity]
Acarina 12 (2), 121-139
Abstract: To determine electrophoretypes based on malat-dehydrogenase (MDH) allele structure, as well as exoskeleton anomalies, heavy metal ion content and tick-borne pathogen infection, over 7,000 Ixodes persulcatus Schulze and Ixodes ricinus (L.) adults and nymphs were collected by flagging in different parts of Eurasia, ranging from Denmark to the Far East of Russia, and studied.
A comparison of the distribution of l. persulcatus MDH-genotypes with areas of three genogroups of tick-borne encephalitis virus (TBEV) existing over Eurasia suggests that the prevalence of the second virus genogroup (Western, Neudoerfl one) correlates with the first genotype of ticks (alleles 1.1, based on MDH-enzyme detection), whereas the existence of the third (Urals-Siberian, Lesopark) and, partly, first (Far Eastern) virus genogroups depends on the location of tick genotype 4 (heterozygous, alleles 1.3 of MDH-enzyme).
Environmental pollution, the appearance of Ixodes ticks with exoskeketon anomalies which are cadmium ion-tolerant, their increasingly vast distribution in time and space, all this alters tick vector capacity and behavior, enhances their capability to be dually or triple infected, and most probably to increase the emergence of microscopically invisible forms (or cell wall-free, or L-form) of borreliae responsible for such dangerous consequences of Lyme disease as Parkinsonism, multiple sclerosis, neuritis etc. The difference in Cd content between the normal ticks and those with anomalous exoskeletons varies from 1: 1.26 (Denmark) to 1 : 1.92 (Far East, Vladivostok Region, Russia), even up to 1: 5.4 (Kalinigrad Region, near a highway).
Genetic (enzymological) and phenetic (hereditary) analyses of the heterogeneity of Ixodes population structure can serve as a powerful tool for the understanding of the intimate properties of Ixodes ticks determining their distribution, vector capacity and dangerousness.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
(original language: Russian)
Database assignments for author(s): Andrey N. Alekseev
Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
Pest and/or beneficial records:
| Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
|---|---|---|---|---|
| Ixodes ricinus | ||||
| Ixodes persulcatus |
