Chlamydia
is a serious debilitating disease that can be fatal to koalas. In the Clarence
Valley the most common symptom of the disease is ocular conjunctivitis, where
one or both eyes become watery, gummy and increasingly inflamed, to a point
where the koala is blinded by the swollen membrane. Urine-stained wet fur
around the tail-end is also a sign of a urogenital form of the disease, which
is related to infertility, uterine and ovarian cysts in females, and death.
All
koala populations carry the chlamydia bacterium: however the actual onset of
disease is triggered by chronic stress. Each year large numbers of koalas die
through vehicle collisions, domestic animal attacks, habitat destruction and
fragmentation by land-clearing and logging; and from starvation and thirst
where moisture and nutrients are removed from eucalypt leaves by drought.
However any koala that survives the initial trauma will inevitably suffer an
onset of chlamydia, sounding its death knell if left untreated.
This means that if chlamydia can only be targeted
and eliminated, koala populations will have a much better chance of
stabilisation and survival in the wild (Rhodes
et al., 2011). To target chlamydia therefore is the obvious option, and
research has been underway for some time in developing an effective vaccine.
Now the outcome is looking
excitingly positive. While some work still needs to be done, vaccinations
performed on both healthy and diseased koalas are providing strong evidence
that a chlamidial vaccine will be successful.
Vaccination trials currently
underway in SE Queensland will shortly be moving outside that state, and from
captive animals to wild koalas. These will include koalas taken into care by
wildlife care groups within NSW. Dr Adam Polkinghorne of Queensland University
of Technology states that the work and collaboration of the latter groups will
be essential to the success of this koala chlamydia vaccine.
Happily this will mean that
koalas brought into care by Clarence Valley WIRES will also be taking part in
this exciting, groundbreaking research to save our iconic marsupial.
- Patricia Edwards
Apr14.JPG) | |||
| Koala in care. Rusty brown fur indicates poor health. |
