novel theileria genotypes from wildlife in a theileria parva—endemic area in kenya

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0 Novel Theileria genotypes from wildlife in a Theileria parva-endemic area in Kenya Naftaly Githaka 1 , David Odongo 2 , Isaac Lekolool 3 , Saturo Konnai 4 and Richard Bishop 1 1 International Livestock Research Institute, ILRI, P.O. Box 30709-00100, Nairobi, Kenya. 2 School of Biological Sciences, University of Nairobi, P.O. Box 30197-00100 Nairobi Kenya. 3 Kenya Wildlife Service, P.O. Box 40241-00100 Nairobi Kenya. 4 Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan. The results from this investigation provided no evidence that waterbuck plays a role in the transmission of T. parva. However, the finding of novel Theileria types, genetically related to pathogenic species occurring in both equids and small ruminants is an unexpected result and worthy of further investigation. The finding of a T. equi-like parasite in a non-equid host species is of interest since recent data suggests that T. equi occupies an intermediate phylogenetic position with respect to Theileria and Babesia (Kappmeyer et al., 2012). Naftaly Githaka [email protected] Box 30709 Nairobi Kenya +254 20 422 3655 www.ilri.org This document is licensed for use under a Creative Commons Attribution –Non commercial-Share Alike 3.0 Unported License In Africa, the primary cause of theileriosis in cattle is the sporozoan parasite Theileria parva that occurs naturally in the Cape buffalo (Syncerus caffer). Waterbuck are infested by large numbers of Rhipicephalus appendiculatus, the tick vector for T. parva, and previous in vitro data suggests that the species may be a source of T. parva transmission to cattle. However, there is no evidence that T. parva is transmissible to the waterbuck under field conditions. TBDs transmission Livestock Wildlife Host interface Pictures ? ? T. parva transmission ? Trends in Parasitology, 2009 Buffalo Cattle ? ? T. parva transmission ? Waterbuck Sampling sites: Marula area (a T. parva-endemic area in Kenya) Blood samples: Detection of parasites: 1)A nested PCR assay targeting a highly conserved region of T. parva single copy gene p104 2)Reverse Line Blot (using oligo probes for all Theileria species so far described in livestock and wildlife in Kenya) Genetic analysis Cloning and sequencing of the 18S rRNA and ITS gene markers Cattle (n=86) Waterbucks (n=26) Marula Results Background Materials and Methods A Cattle samples: 1-18 -ve 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 17 18 Theileria sp (kudus) Theileria/Babesia catch-all Theileria catch-all Theileria annulata Theileria buffeli Theileria equi Theileria sp (giraffe) 1 Theileria sp. (buffalo) Theileria velifera Theileria sp (sable) Theileria mutans Theileria parva Theileria tautoragi Positive controls -ve Waterbuck samples: 1-18 RLB assay PCR No (%). of PCR positive for T. parva-specific p104 gene Waterbucks Cattle 58 / 86 (67.4%) 0 / 26 (0%) No T. parva in the Waterbuck Cattle samples: 1-18 Waterbuck samples: 1-18 P M P M Detection of new Theileria spp. -ve 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 17 18 A C B Conclusion and significance of the findings T. parva and Theileria sp (buffalo) detected in the cattle but not waterbuck samples. Phylogenetic analysis of the 18S rRNA and ITS sequences within the RLB-positive waterbuck samples revealed the occurrence of three Theileria genotypes of unknown identity: Group A clustered with Theileria equi, a pathogenic Theileria species infective to domestic equids. Group B parasites clustered closely with Theileria luwenshuni while Group C was closely related to Theileria ovis that is infective to sheep.

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Poster prepared by Naftaly Githaka, David Odongo, Isaac Lekolool , Saturo Konnai and Richard Bishop for the 8 International Congress on Ticks and Tick-Borne Pathogens (TTP8) and 12 Biennial Conference of the Society for Tropical Veterinary Medicine (STVM 12), South Africa, 24-29 August 2014

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Page 1: Novel Theileria genotypes from wildlife in a Theileria parva—Endemic area in Kenya

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Novel Theileria genotypes from wildlife in a Theileria parva-endemic area in Kenya Naftaly Githaka1, David Odongo2, Isaac Lekolool3 , Saturo Konnai4 and Richard Bishop1

1International Livestock Research Institute, ILRI, P.O. Box 30709-00100, Nairobi, Kenya. 2School of Biological Sciences, University of Nairobi, P.O. Box 30197-00100 Nairobi Kenya. 3Kenya Wildlife Service, P.O. Box 40241-00100 Nairobi Kenya. 4Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo,

Hokkaido 060-0818, Japan.

The results from this investigation provided no evidence that waterbuck plays a role in the transmission of T. parva. However, the finding of

novel Theileria types, genetically related to pathogenic species occurring in both equids and small ruminants is an unexpected result and

worthy of further investigation. The finding of a T. equi-like parasite in a non-equid host species is of interest since recent data suggests that

T. equi occupies an intermediate phylogenetic position with respect to Theileria and Babesia (Kappmeyer et al., 2012).

Naftaly Githaka

[email protected] ● Box 30709 Nairobi Kenya ● +254 20 422 3655

● www.ilri.org

This document is licensed for use under a Creative Commons Attribution –Non commercial-Share Alike 3.0 Unported License

In Africa, the primary cause of theileriosis in cattle is the sporozoan parasite Theileria parva that

occurs naturally in the Cape buffalo (Syncerus caffer). Waterbuck are infested by large numbers of

Rhipicephalus appendiculatus, the tick vector for T. parva, and previous in vitro data suggests that the

species may be a source of T. parva transmission to cattle. However, there is no evidence that

T. parva is transmissible to the waterbuck under field conditions.

TBDs

transmission

Livestock

Wildlife

Host interface

Pictures

? ? T. parva

transmission ?

Trends in Parasitology, 2009 Buffalo

Cattle

? ? T. parva

transmission ?

Waterbuck

Sampling sites:

Marula area (a T. parva-endemic area in Kenya)

Blood samples:

Detection of parasites:

1)A nested PCR assay targeting a highly conserved region of T. parva single copy gene p104

2)Reverse Line Blot (using oligo probes for all Theileria species so far described in livestock and wildlife in Kenya)

Genetic analysis

Cloning and sequencing of the 18S rRNA and ITS gene markers

Cattle (n=86) Waterbucks (n=26)

Marula

Results

Background

Materials and Methods

A

Cattle samples: 1-18

-ve 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 17 18

Theileria sp (kudus)

Theileria/Babesia catch-all

Theileria catch-all

Theileria annulata

Theileria buffeli

Theileria equi

Theileria sp (giraffe) 1

Theileria sp. (buffalo)

Theileria velifera

Theileria sp (sable)

Theileria mutans

Theileria parva

Theileria tautoragi

Positive controls

-ve

Waterbuck samples: 1-18 RLB assay

PCR No (%). of PCR positive for T. parva-specific p104 gene

Waterbucks Cattle

58 / 86 (67.4%) 0 / 26 (0%)

No T. parva in the Waterbuck

Cattle samples: 1-18 Waterbuck samples: 1-18 P M P M

Detection of new Theileria spp.

-ve 9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 17 18

A

C

B

Conclusion and significance of the findings

• T. parva and Theileria sp (buffalo) detected in the cattle but not waterbuck samples.

• Phylogenetic analysis of the 18S rRNA and ITS sequences within the RLB-positive waterbuck samples revealed the occurrence of three Theileria genotypes of unknown identity:

• Group A clustered with Theileria equi, a pathogenic Theileria species infective to domestic equids. Group B parasites clustered closely with Theileria luwenshuni while Group C was closely related to Theileria ovis that is infective to sheep.