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Identification of a Ninth Foot-and-Mouth Disease Virus Type O Topotype and Evidence for a Recombination Event in its Evo

IAH. WRLFMD. Identification of a Ninth Foot-and-Mouth Disease Virus Type O Topotype and Evidence for a Recombination Event in its Evolution. Nick J. Knowles, Paul R. Davies, Rebecca J. Midgley and Jean-François Valarcher

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Identification of a Ninth Foot-and-Mouth Disease Virus Type O Topotype and Evidence for a Recombination Event in its Evo

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  1. IAH WRLFMD Identification of a Ninth Foot-and-Mouth Disease Virus Type O Topotype and Evidence for a Recombination Event in its Evolution Nick J. Knowles, Paul R. Davies, Rebecca J. Midgley and Jean-François Valarcher Institute for Animal Health, Pirbright Laboratory, Ash Road, Woking, Surrey, GU24 0NF, UK

  2. IAH WRLFMD FMDV O in Africa

  3. IAH WRLFMD Previous studies • Few studies on the European FMDV serotypes in Africa: • Knowles et al., 1998 (type A) • Samuel et al., 1999 (type O) • Samuel & Knowles, 2001 (type O) • Sangare et al., 2001 (type O) • Sahle et al., 2004 (type O) • Bronsvoort et al., 2004 (types O & A) • Distinct genetic lineages of both FMDV-O and FMDV-A circulate in East and West Africa and viruses occurring in North Africa may be introduced from a variety of sources (Europe, South America, Middle East and West Africa). • Outbreaks of FMD types O and A in southern Africa are very rare and are usually introduced from outside the continent.

  4. IAH WRLFMD FMDV O Topotypes - 2001 Samuel, A.R. & Knowles, N.J. 2001. Foot-and-mouth disease type O viruses exhibit genetically and geographically distinct evolutionary lineages (topotypes). J. Gen. Virol. 82: 609-621.

  5. IAH WRLFMD RT-PCR & Sequencing Capsid Non-structural proteins L P1 P2 P3 5’ UTR 3’ UTR IRES VPg AAAAAAAAAn 3D VP4 VP2 VP3 VP1 2A 2B 2C 3A 3B 3C Poly C O-1C244F O-1C272F O-1C283F NK61 NK61 NK61

  6. IAH WRLFMD VP1(complete)

  7. IAH WRLFMD VP1(145-642)

  8. IAH WRLFMD VP1(478-642)

  9. IAH WRLFMD Scanning analysis of VP1

  10. IAH WRLFMD Scanning analysis of VP1

  11. IAH WRLFMD Occurrence of FMDV O Topotypes in Africa

  12. IAH WRLFMD FMDV O Topotypes - 2004 East Africa 1 (EA-1) South-east Asia (SEA) West Africa (WA) O/UGA/5/96 O/ALG/1/99 O/CIV/8/99 O/TAI/4/99 O/KEN/2/95 O/KEN/83/79 O/CAM/2/98 O/GHA/5/93 O/TAW/81/97 O/VIT/7/97 Middle East-South Asia (ME-SA) O/PHI/7/96 O/IRQ/30/2000 Cathay O/HKN/14/82 O1/Manisa/TUR/69 O/A/CHA/58 O/ISA/8/83 O/BUN/7/2003 Indonesia-1 (ISA-1) O/KEN/5/2002 O/ISA/9/74 O/KEN/7/2002 East Africa 2 (EA-2) O/KEN/3/2002 O/UGA/3/2002 O/ISA/1/62 O/TAN/7/98 O/MAL/1/98 O/JAV/5/72 1% O/ISA/1/74 O2/Brescia/ITL/47 O3/VEN/51 Indonesia-2 (ISA-2) Europe-South America (Euro-SA) O1/Kaufbeuren/FRG/66

  13. IAH Future work • We are completing the complete capsid sequencing of 9 African FMDV O isolates including representatives of all indigenous topotypes • We have an on-going study of FMDV O in Africa • We have completed a study of FMDV A in Africa (~80 VP1 sequences)

  14. IAH WRLFMD Conclusions • Two previously unrecognised genetic lineages of FMDV O were identified in East Africa, each having a distinct geographic distribution. • Recombination near the 3’ end of VP1 may have played a role in the evolution of the EA-2 topotype. • Alternatively, it may be that all the African lineages evolved after the introduction of Asian FMD viruses into Africa and more mutations have subsequently accumulated in certain parts of the capsid-coding region while other parts may have remained more conserved.

  15. IAH WRLFMD Recommendations • Future phylogenetic analyses for molecular epidemiological purposes should be based on complete VP1 sequences. • More extensive molecular epidemiological studies of the European FMDV serotypes in Africa should be undertaken (this is in progress in our laboratory for serotypes O and A). • More extensive genome analyses need to be performed to access the role of recombination in the natural evolution of FMD viruses.

  16. IAH WRLFMD Acknowledgements • Nigel Ferris & Geoff Hutchings • for viruses • Rahana Dwarka & Wilna Vosloo • for sequences

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