Parasitology Research

, Volume 101, Supplement 2, pp 183–186

Ticks status in Central Asia with a special emphasis on Uzbekistan

Authors

    • Department of Protozoology, Institute of ZoologyAcademy of Science
Original Paper

DOI: 10.1007/s00436-007-0691-8

Cite this article as:
Rasulov, I. Parasitol Res (2007) 101: 183. doi:10.1007/s00436-007-0691-8

Abstract

Uzbekistan is located between the greatest rivers of Central Asia and shares borders with Kazakhstan to the west and to the north, Kyrgyzstan and Tajikistan to the east, and Afghanistan and Turkmenistan to the south. The climate is severely continental and arid, with hot summers and cold winters. These climatic particularities of Uzbekistan determine the distribution of tick fauna. The Ixodidae family of ticks is represented by 23 species in Uzbekistan. These ticks, as ectoparasites, cause significant damage to the livestock breeding and also serve as carriers of many human and animal diseases. During the last 10 years, more than 30,000 ticks in different regions of Uzbekistan were collected and identified. Analysis showed that cattle are parasitized by 11 species of Ixodidae ticks. The dominating species were Hyalomma anatolicum (34.9%), Hyalomma detritum detritum (31.8%), Boophilus kohlsi (30.7%).

Introduction

Uzbekistan is located between the largest rivers of Central Asia, Amu-Darya, Sir-Darya, Zaravshan, and Chirchik. Uzbekistan shares borders with Kazakhstan to the west and to the north, Kyrgyzstan and Tajikistan to the east, and Afghanistan and Turkmenistan to the south. Uzbekistan’s climate is classified as continental, with hot summers and cool winters. Summer temperatures often surpass 40°C; winter temperatures average about −23°C, but may fall as low as −40°C. Most of the country also is quite arid, with average annual rainfall amounting to between 100 and 200 mm and occurring mostly in winter and spring. Between July and September, little precipitation falls, essentially stopping the growth of vegetation during that period. Such climatic particularities determine the spread of ticks and also the human and animal diseases they transmit.

Farmers in high-risk areas consider ticks to be an important constraint which result in a significant reduction in income and are particularly serious for livestock-dependent systems. Besides reduction in milk production, the direct effect of tick infestation has tremendous effect on the availability of good quality hides for the leather industry, as tick bite marks have been identified as one of the factors causing reduction in normal value in the market. Production of the animals is affected also due to deaths, which have been recorded because ticks transmit important protozoan diseases like babesiosis and theileriosis.

The present review was prepared based on information raised by a number of studies conducted by scientists from Uzbekistan, Kazakhstan, Kyrgyzstan, Tajikistan, and Turkmenistan. The focus is, however, on ticks found in different regions of Uzbekistan such as Tashkent, Djizak, Syrdariya, Kashkadariya, Bukhara, and Samarkand. More than 30,000 Ixodidae ticks were examined.

Ticks of Ixodidae and Argasidae family found in Uzbekistan

Tick species identified during the 10-year survey are listed in Table 1. Most of the listed species have already been described to occur in Central Asia (http://www.wrbu.org/centcom_TK.html; http://www.wrbu.org/ticklit_centcom.html; http://www.afpmb.org/lrs; compiled from the literature as cited in, e.g., Pomerantsev 1948; Rachinina and Malygina 1964; Kuklina 1967; Mel´chakova et al. 1969; Kusov and Mel`chakova. 1971; Urakov 1973; Filippova 1974), but also include some species apparently not recorded before (Hyalomma impressum, H. turanicum, Dermacentor daghestanicus, Araneus canestrinii, Boophilus kohlsi, H. punctata, and H. sulcata). Table 2 shows the geographical distribution of Hyalomma species in Uzbekistan.
Table 1

Ticks of the Ixodidae and Argasidae family found in Uzbekistan

Tick families

Family Ixodidae

 Genus Hyalomma Koch 1844

Hyalomma aegyptium Linnaeus 1758

Hyalomma anatolicum anatolicum Koch 1844

Hyalomma anatolicum excavatum Koch 1844

Hyalomma asiaticum Schulze and Schlottke 1930

Hyalomma detritum detritum Schulze 1919

Hyalomma dromedarii Koch 1844

Hyalomma impressum Koch 1844

Hyalomma turanicum Pomerantsev 1946

Hyalomma detritum scupense Schulze 1918

 Genus Rhipicephalus

Rhipicephalus leporis Pomerantsev 1948

Rhipicephalus pumilio Schulze 1935

Rhipicephalus rossicus Yakimov and Kol-Yakimova 1911

Rhipicephalus schulzei Olenev 1929

Rhipicephalus turanicus Pomerantsev 1936

 Genus Boophilus Curtice 1891

Boophilus kohlsi Hoogstral and Kaiser 1960

 Genus Dermacentor

Dermacentor daghestanicus Olenev, 1929

Dermacentor marginatus Sulzer, 1776

Dermacentor pavlovskyi Olenev, 1927

Dermacentor reticulatus Fabricius, 1794

 Genus Haemaphysalis Koch 1844

Haemaphysalis concinna Koch 1844

Haemaphysalis erinacei turanica Pospelova-Shtrom 1940

Haemaphysalis sulcata Canestrini and Fanzago 1878

Haemaphysalis punctata Canestrini and Fanzago 1878

Family Argasidae

 Genus Argas Latreille 1795

Argas persicus Oken 1818

Argas reflexus Fabricius 1794

Argas canestrinii Birula 1895

 Genus Ornithodoros Koch 1837

Ornithodoros cholodkovskyi Pavlovsky, 1930

Ornithodoros tartakovskyi Olenev 1931

Ornithodoros tholozani Laboulbene and Mégnin 1882

 Genus Carios Latreille 1796

Carios vespertilionis Latreille 1796

Table 2

Geographical distribution (in %) of main Hyalomma species in different regions of Uzbekistan

Region

H. detritum

H. anatolicum anatolicum

H. anatolicum excavatum

H. turanicum

H. asiaticum asiaticum

H. dromedarii

Mirzachul

63.4

14.7

17.5

4.4

Kara Darya

94.5

4.4

0.9

0.2

Kirov

47.6

34.3

0.2

0.1

17.8

Zaamin

11.6

74.0

0.3

13.5

0.6

Farish

2.2

43.8

0.6

53.0

0.4

Urgut

12.2

49.1

38.7

Parkent

6.4

31.9

0.1

60.3

1.3

Djizack

6.1

85.8

1.5

6.6

Past-dargom

1.7

14.5

83.7

0.1

Karakul (watering zones)

40.8

27.9

23.5

0.1

6.8

0.9

Karakul (zone of sands)

0.1

22.4

77.5

Animal hosts infested by different tick species

Table 3 shows the ticks and their vertebrate hosts. It is apparent that the majority of the ticks use the same range and animal host. B. kohlsi, H. detritum detritum, H. anatolicum anatolicum, H. asiaticum, and H. turanicum feed on cattle and horses, whereas Rhipicephalus turanicus, H. punctata, and H. sulcata preferably use small ruminants. H. dromedarii infests camels, but rarely cattle or other animals.
Table 3

Hosts of ticks of ixodidae family in Uzbekistan

Tick species

Cattle

Sheep

Goats

Horses

Camels

Donkeys

Pigs

Dogs

Hares

Gophers

Jerboas

Sander lings

Hedgehogs

Terrapins

Mountain sawhorse

B. calcaratus

+

+

+

+

+

+

+

H. detritum

+

+

+

+

+

+

+

+

H. anat. anatolicum

+

+

+

+

+

+

+

+

H. anat. excavatum

+

+

+

+

+

+

+

+

+

H. asiaticum

+

+

+

+

+

+

+

+

+

+

+

+

H. turanicum

+

+

+

+

+

+

+

+

+

+

+

+

+

H. impressum

+

+

H. dromedarii

+

+

+

+

+

H. aegyptium

+

H. scupense

+

Rh. turanicus

+

+

+

+

+

+

+

+

+

+

Rh. pumilio

+

+

+

+

+

+

+

Rh. rossicus

+

Rh. schulzei

+

Rh. leporis

+

+

D.daghestanicus

+

+

+

+

+

+

+

D. marginatus

+

+

+

+

D. reticulatus

+

D. pavlovskyi

+

H. punctata

+

+

+

+

+

H. sulcata

+

+

+

+

H. erinacei turanica

+

H. concinna

 

+

Non-puberty stages of some tick species also preferred determined host type. Larvae and nymphs of B. kohlsi, H. detritum detritum, and H. anatolicum anatolicum exceptionally parasitized on large cattle and horses. Non-puberty stages of others species of ixodidae ticks feed on different wild animals (rodents, reptiles) and on birds.

Seasonal distribution

Based on the seasonal distribution, ticks in Uzbekistan can be divided into three categories:
  1. 1)

    D. daghestanicus, H. sulcata, H. punctata, R. turanicus appear in spring

     
  2. 2)

    B. kohlsi, H. anatolicum anatolicum, H. anatolicum excavatum, H. impressum appear in spring–summer–autumn

     
  3. 3)

    R. turanicus and H. asiaticum, H. detritum detritum appear around the year.

     

Zonal tick distribution

Based on climatic conditions, the distribution can be classified into three zones: relief, steppe, foothills and mountains. The plains zone can be divided into regions of relief-foothills, with predominance of grass and thick grass cover and regions of arid plains with xerophilous plants and rare field grasses. Predominant species in this zone are B. kohlsi (47–67%) and H. detritum detritum (16–49%). Fewer numbers of H. anatolicum anatolicum, H. turanicum, H. asiaticum, R. turanicus, D. daghestanicus, H. punctata, and H. sulcata are observed.

The arid zone, non-irrigated plains (desert) are characterized by dominant xerophilous tick forms, typical for desert and semi-deserts habitats, namely, H. asiaticum and H. anatolicum excavatum. The first species makes up 65–89% to others species of Ixodidae in desert zone (Bukhara zone), the second 10.4–34.6%. In total, four species of Ixodidae ticks have registered for this zone, the other two being H. anatolicum anatolicum and R. turanicus, but only in low numbers. In the zone of the sandy desert, the ticks-vectors of piroplasmosis of large cattle (B. kohlsi) and of theileriosis of the large cattle (H. detritum detritum) are absent. The paucity of species composition of ixodaphauna of the plain-desert zone is explained by the disadvantages in climatic conditions, high temperature, dryness of the air, and scarcity of grass.

The steppe zone and foothills (with the drier climate) is characterized by a large variety of ixodaphauna; 14 species of ticks have been described here. The following species were predominantly found: H. turanicum, H. anatolicum anatolicum, and R. turanicus. Less predominant were B. kohlsi, H. detritum detritum, and H. asiaticum; other species were single findings.

In the mountain zone over 1,500 m above sea level, not many representatives of the Ixodidae family are found. According to the data of the survey, H. turanicum, H. anatolicum anatolicum, R. turanicus, D. reticulatus, D. pavlovskyi, and D. marginatus were found in this zone.

Ticks as transmitters of blood protozoan parasites

Like in other Central Asian countries, ticks are responsible for the transmission of a number of bacterial, viral, and parasitic pathogens in Uzbekistan. The vector ticks, which transmit Theileria, Babesia, and Anaplasma to livestock, are well characterized. However, little is known about the transmission of piroplasms to sheep. Although piroplasms have been demonstrated in sheep, the vector ticks are not well characterized.

Within the last 10 years, we have studied 3,285 blood samples and punctata of lymphatic nodes taken from sick and emergency slaughtered animals. We found that in different regions of Uzbekistan, cattle are infected by three parasites which are transmitted by ixodidae ticks: T. annulata (56.6%), B. bigemina (23.5%), and B. bovis (8.6%). Taking all these parasites together, 12% of the examined animals were infected.

There is an urgent demand of intensive studies regarding the prevalence of ticks and diseases they transmit with a focus on the socioeconomic impact of ticks and tick-borne diseases in Uzbekistan and Central Asia as a whole.

Acknowledgement

This study was funded in part by the EU coordinated action ICTTD-3 (contract no. IC18-CT95-0009).

Copyright information

© Springer-Verlag 2007