Changes

==Prevention==

==Prevention==

===Prophylaxis===

===Prophylaxis===

A killed vaccine, developed using ''S.neurona'' merozoites, was conditionally licensed for use in horses.<ref>Saville, W.J.A, Reed, S.M, Dubey, J.P (2002) Prevention of equine protozoal myeloencephalitis(EPM). ''Proceedings of the Annual Convention of the AAEP'', 48:181-185.</ref>  The vaccine proved to be ineffective in the prevention of EPM and has since been removed from the market.<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>  There is evidence to suggest that the antiprotozoal, ponazuril, may be useful prophylactically to reduce the incidence and severity of clinical signs.<ref>Furr, M, MacKenzie, H, Dubey, J.P (2006) Pretreatment of horses with ponazuril limits infection and neurologic signs resulting from S.neurona.  ''J Parasitol'', 92:637-643.  In: Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>  Implementing such a regime prior to and during stressful events may be beneficial, although the cost is likely to be prohibitive.<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>Protocols involving intermittent administration of ponazuril may also show promise in the prevention of EPM.<ref>Mackay, R.J, Tanhauser, S.T, Gillis, K.D, Mayhew, I.G, Kennedy, T.J (2008) Effect of intermittent oral administration of ponazuril on experimental ''Sarcocystis neurona'' infection of horses.  ''Am J Vet Res'', 69(3):396-402.</ref>

A killed vaccine, developed using ''S.neurona'' merozoites, was conditionally licensed for use in horses.<ref name="Saville1">Saville, W.J.A, Reed, S.M, Dubey, J.P (2002) Prevention of equine protozoal myeloencephalitis(EPM). ''Proceedings of the Annual Convention of the AAEP'', 48:181-185.</ref>  The vaccine proved to be ineffective in the prevention of EPM and has since been removed from the market.<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>  There is evidence to suggest that the antiprotozoal, ponazuril, may be useful prophylactically to reduce the incidence and severity of clinical signs.<ref>Furr, M, MacKenzie, H, Dubey, J.P (2006) Pretreatment of horses with ponazuril limits infection and neurologic signs resulting from S.neurona.  ''J Parasitol'', 92:637-643.  In: Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>  Implementing such a regime prior to and during stressful events may be beneficial, although the cost is likely to be prohibitive.<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>Protocols involving intermittent administration of ponazuril may also show promise in the prevention of EPM.<ref>Mackay, R.J, Tanhauser, S.T, Gillis, K.D, Mayhew, I.G, Kennedy, T.J (2008) Effect of intermittent oral administration of ponazuril on experimental ''Sarcocystis neurona'' infection of horses.  ''Am J Vet Res'', 69(3):396-402.</ref>

===Control===

===Control===

Control of EPM is challenging because there are a variety of intermediate hosts for ''S.neurona'' and this parasite is very widely distributed.<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref> The definitive host, the opossum, is also a scavenger and will consume road-kill, including species that are putative intermediate hosts for ''S.neurona''.(IVIS 1)  A number of control measures are recommended:

Control of EPM is challenging because there are a variety of intermediate hosts for ''S.neurona'' and this parasite is very widely distributed.<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref> The definitive host, the opossum, is also a scavenger and will consume road-kill, including species that are putative intermediate hosts for ''S.neurona''.<ref name="Saville1">Saville, W.J.A, Reed, S.M, Dubey, J.P (2002) Prevention of equine protozoal myeloencephalitis(EPM). ''Proceedings of the Annual Convention of the AAEP'', 48:181-185.</ref> A number of control measures are recommended:

*Deny wildlife access to feed (use rodent-proof containers, protect forages in enclosed facilities,<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref> remove fallen fruit and bird feeders)(Merck)

*Deny wildlife access to feed (use rodent-proof containers, protect forages in enclosed facilities,<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref> remove fallen fruit and bird feeders)<ref name="Merck">Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial</ref>

*Prevent access of opossums to horse-feeding areas

*Prevent access of opossums to horse-feeding areas

*Remove carcasses from roads and property (especially those of skunks, raccoons, armadillos and cats which may act as intermediate hosts)(IVIS 1)

*Remove carcasses from roads and property (especially those of skunks, raccoons, armadillos and cats which may act as intermediate hosts)<ref name="Saville1">Saville, W.J.A, Reed, S.M, Dubey, J.P (2002) Prevention of equine protozoal myeloencephalitis(EPM). ''Proceedings of the Annual Convention of the AAEP'', 48:181-185.</ref>

*Opossums can be trapped and relocated.  (Merck)

*Opossums can be trapped and relocated<ref name="Merck">Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial</ref>

*Monitor high-risk horses closely to help detect EPM early

*Monitor high-risk horses closely to help detect EPM early<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>

==References==

==References==