Teresia Maina (right) and supervisor Jose Perez-Casal are part of the VIDO-InterVac cattle vaccine team (photo by David Stobbe).

Vital vaccine candidates for cattle

Raised on a farm in Kenya, Teresia Maina has seen firsthand the devastating effects of “lung plague” on cattle and the resulting economic hardships for her community.

With only a few head of cattle, small farms like her family's suffer financially when cows become infected with this devastating disease, which has a 50 per cent death rate.

After hearing former VIDO-InterVac director Lorne Babiuk speak at an agricultural institution in Kenya, Maina decided that the University of Saskatchewan centre was the right place to fulfill her dream of developing a new vaccine for the disease.

"A chance to create a better living and ensure food security for my people through vaccine production was all the incentive I needed," said Maina, now a U of S PhD student in veterinary microbiology.

Caused by the highly infectious Mycoplasma mycoides bacterium that attacks the respiratory system, "lung plague" (contagious bovine pleuropneumonia) causes more than $60 million in annual losses in Africa, affecting the livelihood of 24 million people. If the cows survive, they continue to carry the bacteria and can infect other cattle.

A distant bacterial cousin, Mycoplasma bovis, is present in Canada and causes significant economic losses for cattle and bison producers.

Over the past two years, Maina has been working with a team of researchers at the U of S and in Kenya to identify the genes responsible for "lung plague" and the proteins that could be used as antigens to trigger the animal's immune system against the disease.

She has helped find potential vaccine candidates at VIDO-InterVac, a world leader in infectious disease and vaccine research and development. The team's results, presented last June at a symposium in Kenya, showed that some of the vaccine candidates were effective in clinical trials.

The new experimental vaccines hold promise to be cost effective, safe, and easily produced and stored. Existing vaccines are expensive, only effective in the short term, and need constant refrigeration, which is impractical in many parts of Africa.

The potential vaccine candidates will be fully tested in Africa during the next three years, working with agricultural organizations in Kenya.

The vaccine platform could also be adapted for similar but less dangerous respiratory diseases in North American cows and bison, says Maina's supervisor, Jose Perez-Casal.

Effective vaccination would dramatically decrease veterinary expenses for producers. Also, fewer animals would get sick and need to be treated with antibiotics, reducing the antibiotic runoff on feedlots and the emergence of antibiotic-resistant bacteria.

The international partnership is led by VIDO-InterVac director Andrew Potter, associate director of research Volker Gerdts, and program manager Perez-Casal. Hezron Wesonga, a scientist at the Kenya Agricultural and Livestock Research Organization, leads the research in Africa.

"The combination of scientists, post-doctoral fellows and students from several countries working at VIDO-InterVac, together with Kenyan scientists' knowledge and field experience with the disease, makes the partnership between Canada and Kenya unique," Maina said.

Funding was provided by the International Development Research Centre and Foreign Affairs, Trade and Development Canada through the Canadian International Food Security Research Fund. The Kenya Veterinary Vaccines Production Institute will ultimately produce the vaccine.


Article written by Federica Giannelli, a graduate student intern in the U of S research profile and impact unit. This article first ran as part of the 2015 Young Innovators series, an initiative of the U of S Research Profile office in partnership with the Saskatoon StarPhoenix.
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