Beware of Wesselsbron disease

A Wesselsbron disease outbreak in sheep has been confirmed in Aberdeen in the Eastern Cape, according to the monthly report on livestock disease trends as informally reported by veterinarians belonging to the Ruminant Veterinary Association of South Africa (RuVASA).

Wesselsbron disease is similar but less dangerous than Rift Valley Fever. It is transmitted by mosquitoes. Lambs are most susceptible and many die. Calves, adult cattle, sheep and goats survive but may abort.

People may develop flu symptoms from mosquito bites, handling animals, afterbirths and post mortems. A live vaccine is periodically available from Onderstepoort Biological Products. There is no specific treatment and infected persons should be nursed well.

In the present outbreak there were no abortions.

Mortality in sheep and Angora goats are less than 5%. Clinical signs observed are serous abdominal pain, fever, icterus and deaths within 24 to 36 hours. Luckily very few small-stock are presently pregnant.

The February disease report showed a huge increase in tick and insect transmitted diseases. These diseases could have been prevented if animals were vaccinated according to a management programme drawn up in conjunction with a veterinarian.