1. Dermacentor reticulatus Arthropoda:Acarina:Ixodidae
MOLECULAR GENETIC ANALYSIS OF TICK-BORNE INFECTIONS IN THE WESTERN SIBERIA, RUSSIA
Ixodes persulcatus
Dermacentor reticulatus
Arthropoda:Acarina:Ixodidae
Ixodid ticks maintain and transmit bacteria, rickettsia, viruses and protozoan agents to mammalian hosts, including human beings.
Transmission of the tick-borne pathogens through farm and domestic animals, wild terrestrial mammals and ground-foraging birds, dairy products, transfusion and organ transplantation poses an additional risk to a world population.
Tick-borne encephalitis virus have been recognized as potential bioterrorism agent and designated as category C agents on the NIAID list.

2. Transmission cycle of the tick-borne infections
showing man as a dead-end host
Raw milk and
dairy products from cows, sheep, goats
Mammals
Birds
Reptiles
Amphibians
transfusion and organ transplantation

3. Localization of geographical places where ticks were collected.
Omsk, Tomsk and Novosibirsk regions are shading.

4. Lyme borrelioses
Borrelia burgdorferi sensu lato
Borrelia burgdorferi sensu stricto
Borrelia garinii (groups and NT29)
Borrelia afzelii
In Russia – 8,000 cases annually
Infection rate of Ixodes persulcatus ticks 15-46%
In 2000 – %
In 2001 – %
In 2002 – %
In 2003 – %
In 2004 – %
Average rate – %

5. Bartonella bacilliformis Carrion’s disease
Bartonella henselae
cat scratch disease
Bartonella quintana
trench fever
Bartonella bacilliformis
Carrion’s disease
In Russia antibodies against Bartonella spp % of men near Moscow
Infection rate of Ixodes persulcatus ticks
In %
In 2003 – %
In %
Average rate – %

6. Anaplasma phagocytophila
Ehrlichia ewingii
Human granulocytic ehrlichiosis
Ehrlichia chaffeensis
Human monocytic ehrlichiosis
In Russia 4 serologically confirmed cases of human monocytic ehrlichiosises
Infection rate of Ixodes persulcatus ticks
In 3.9% Ehrlichia spp.
In % (Anaplasma phagocytophila % )
In % (Anaplasma phagocytophila %)

7. Babesia microti
Babesia divergens
Human and animal babesiosises
In Russia several lethal cases of babesioses
Infection rate of Dermacentor reticulatus ticks
In % (Babesia canis canis)
Infection rate of Ixodes persulcatus ticks -

8. Ehrlichia & Anaplasma spp.
Prevalence of different tick-borne agents in ticks in 2003
Prevalence (%)
Ixodes persulcatus
Dermacentor reticulatus
Borrelia spp.
Borrelia afzelii -
Borrelia garinii NT29
Mixed infection Borrelia garinii & Borrelia afzelii
Borrelia novel group
Ehrlichia & Anaplasma spp.
Ehrlichia muris
Anaplasma phagocytophila
Bartonella spp.
Bartonella henselae
Bartonella quintana
Babesia spp.
Babesia canis canis

9. Phylogenic tree of Borrelia burgdorferi s. l
Phylogenic tree of Borrelia burgdorferi s.l. isolates based on 5S-23S rRNA intergenic spacer sequence comparison

10. Natural cycle of ixodid ticks

11. Percentage (%SE) of the TBEV-infected small mammals for 1998-2003
SE – sampling error; sample size is given in parentheses.
Species
RT-PCR
ELISA
brain
liver
both brain or liver
Common shrews
Sorex araneus L.
58.37.1
(48)
62.58.6
(32)
83.36.8
(30)
44.09.9
(25)
70.010.2
(20)
69.212.8
(13)
Field mice Apodemus agrarius Pallas
19.75.1
(61)
31.28.2
40.68.7
16.94.9
(59)
43.39.0
Red voles Clethrionomus rutilus Schreber
48.36.6
(58)
40.011.0
27.66.5
(47)
30.010.2
85.79.4
(14)
Total
40.73.8
(167)
45.25.4
(84)
63.45.3
(82)
33.64.1
(131)
41.75.8
(72)
59.66.5
(57)

12. Borrelia burgdorferi sensu lato
In – % of small mammals
Sorex araneus L. (common shrews)
Apodemus agrarius Pallas (field mice)
Clethrionomus rutilus Schreber (red voles)
HGE agent - Anaplasma phagocytophila
In 2003 – % of small mammals
Clethrionomys rufocanus (grey large-toothed red-backed voles)
Babesia microti in small mammals in Novosibirsk region
In 2003 – % of small mammals
Among them Clethrionomys rufocanus (grey large-toothed red-backed voles)
Apodemus agrarius (field mice)
Sicista betulina (birchmice)

13. Detection of the tick-borne pathogens among patients in Novosibirsk in 2003-2004
Borrelia spp.
In 75 from 416 studied samples from human plasma ( %)
Borrelia garinii (groups NT29 and 20047)
Borrelia afzelii
Bartonella spp.
In 60 from 353 studied samples from blood cells ( %)
Bartonella henselae - 10
Bartonella quintana - 7
Bartonella grahamii - 1

14. Prevalence of human pathogens in Ixodes persulcatus ticks
Pathogen(s)* Ticks examined (N) Prevalence (%  SD)
Borrelia burgdorferi 4.0
TBEV 5.0
Ehrlichia spp 3.9
co-infection
B. burgdorferi-TBEV 3.9
B. burgdorferi- Ehrlichia spp 3.4

15. CONCLUSIONS:
1. Infection of 2 tick species Ixodes persulcatus and Dermacentor reticulatus prevalent in the Western Siberia, Russia and able to bite humans with 3 bacterial and 1 protozoan tick-borne pathogens was studied by nested PCR with genus-specific primers. Both studied tick species contained Borrelia and Bartonella DNA whereas Ehrlichia/Anaplasma DNA was detected in I. persulcatus but Babesia DNA - in D. reticulatus ticks only. The TBEV infection level of I. persulcatus varied from 3 to 30% in different years according to bioassays, whereas RT-PCR revealed 43-46% infected ticks.

16. 2. Along with the ticks, small mammals can contribute to the maintaining of the tick-borne pathogens in natural populations. High infection rate (19-85%) of small rodents and insectivores with the tick-borne encephalitis virus and lower prevalence of Borrelia (6-17%) might suggest the important role of warm-blooded hosts in enzootic cycles.
3. Besides the widely known human pathogens - the tick-borne encephalitis virus and Borrelia the new intracellular bacteria – Bartonella henselae, Bartonella quintana and Bartonella grahamii were detected in blood cells from patients after tick bites. In spite of the presence of the human pathogen Anaplasma phagocytophila in Ixodes persulcatus ticks and the pathogenic Babesia microti among small mammals in the same regions of Western Siberia infections of patients with Anaplasma/Ehrlichia or Babesia spp. were not found.

17. 4. The statistically similar expected and observed values of mixed coinfection of tick and patients with the studied tick-borne infectious agents are consistent with the independent distribution of these pathogens. Therefore, reciprocal inhibition of the studied bacteria and the virus during reproduction in ticks and humans was not observed.
5. Further studies are required to prove the roles of different biting arthropods and insects as natural vectors of the “tick-borne” bacteria, virus and protozoa.

18. Institute of Chemical Biology and Fundamental Medicine
of Siberian Branch of the Russian Academy of Sciences
Olga V. Morozova, Vera A. Rar, Natalya V. Fomenko, Sergey E. Tkachev, Natalya A. Titova
Institute of Systematics and Ecology of Animals
Valentina N. Bakhvalova, Andrey K. Dobrotvorsky, Natalya N. Livanova
Omsk Research Institute of Natural Focus Infections
of the Ministry of Health of Russian Federation
Svetlana A. Rudakova, Valerii V. Yakimenko
Center of Epidemiological Control of Novosibirsk region
Valeriy N. Mikheev, Evgeniy G. Fedorov
State Infectious Hospital №1, Novosibirsk
Nelya Ya.Chernousova, Julya V. Kazakova
Central Clinical Hospital of Siberian Branch of the Russian Academy of Sciences
Lyudmila A. Gosteeva
Novosibirsk State Medical Academy
Natalya P. Tolokonskaya, Ekaterina V. Romanova