| Nature of the disease |
| Enzootic abortion of ewe and goats due to
Chlamydophila abortus formerly known as Chlamyda psittaci. The
disease causes abortion and is a potential zoonosis. |
| Classification |
| OIE, List B disease |
| Susceptible species |
| Goats and sheep and less commonly cattle and deer.
Humans are also susceptible. |
| Distribution |
| Enzootic Abortion of ewe is present in Europe, North
America and in some African Countries. In the Pacific Region is only suspected
in French Polynesia. |
| Clinical signs |
- Abortion,
- Placentitis,
- Low fertility result (as a consequence of abortions)
|
| Post-mortem findings |
| No fatality |
| Differential diagnosis |
| Other causes of abortion in small Ruminants:
|
| Specimens required for diagnosis |
| Smear from placenta material is the best specimen.
Identification of the agent is best done by antigen detection (ELISA,
fluorescent antibody test) or PCR. Culture and isolation is also possible.
For serological test Fixation
Complement and ELISA are available.
|
| Transmission |
| Enzootic abortion is transmited orally by food, water
and straw. It can also be transmitted by aerosol. The organism is shed in
blood and milk for up to 4 months and in the urerus for 6 months. |
| Risk of
introduction |
| Enzootic abortion of ewe can be introduced by
importation of infected small ruminants. It seems that there is no link between
Chlamydophila abortus and
the possibility Chlamydophila abortus of
birds. |
| Control
/ vaccines |
| Inactivated and live vaccines are available that
reduce the incidence of abortion, but do not prevent infection. They assist in
control of the disease but will not eradicate it. Serological screening during
the period after parturition helps to identify infected flocks, to which control
measures can then be applied. |
| References |
- Caprine arthritis/encephalitis, In Merck Veterinary Manual, National
Publishing Inc. Eight ed, 1998, Philadelphia, p 523-526
- Caprine arthritis/encephalitis, In Veterinary Medicine, Saunders,
Eight ed, 1997, London p. 1110-1112
- Office International des Epizooties, 2002
|
