New vaccine tested in kudu rabies project
A vaccine used in an investigation in Europe to inoculate foxes against rabies will not be desirable to use for kudus in Namibia.According to the Namibia Agricultural Union (NAU), the first phases of the kudu rabies project indicated that, in principle, an oral vaccine seems to work.
“It was originally designed for predators. Even though the vaccine tested in Namibia produced a positive result, it has certain challenges,” it said.
According to the union, with this vaccine, kudus require high doses to build up sufficient immunity.
It explained that the administration of high vaccine doses in a natural environment is a practical challenge.
“Bait, camel pods, are hung for kudus to eat. Each pod contains one ampoule of oral vaccine. Although the bait recipe works very well and kudus eat it eagerly, each kudu needs to eat at least five pods to ingest sufficient vaccine.”
This is practically impossible to ensure, the NAU said.
A conclusion reached by experts, along with the Livestock Producers’ Organisation (LPO), is that it is not desirable to continue with the current vaccine.
New vaccine
According to the union, the Friedrich Loeffler Institute (FLI) has been working for several years to design a new vaccine to specifically address the rabies problem in Namibia.
This is a recombinant vaccine that contains a harmless New Castle disease virus as a carrier, to carry a portion of the rabies virus into the animal's body.
The New Castle disease virus is used as it is quickly and easily absorbed into the body through the mucous membranes of an animal. Good results have been achieved by the FLI with goats. The recommendation is to first test boer goats in Namibia and, if successful, the trials will be repeated on kudus, it said.
According to the union, this could possibly be done in the first half of 2023.
“The bait study will also be continued with the new vaccine. This can be dosaged in a higher concentration to ensure that an animal reaches adequate immunity.”
The NAU said in the absence of successful results from vaccinating kudus orally, other possibilities must be considered. The current vaccine can be used to inoculate the vector of the rabies virus, namely jackals.
The project will continue in partnership with the LPO and the University of Namibia.