A new attenuated Mycobacterium bovis vaccine protects brushtail possums (Trichosurus vulpecula) against experimental tuberculosis infection

Vaccination of wildlife against bovine tuberculosis is being actively considered in countries that have wildlife reservoirs of Mycobacterium bovis infection. A newly attenuated strain of M. bovis (WAg533) was produced as part of a programme to develop a better vaccine than BCG to control tuberculosis in brushtail possums in New Zealand. The vaccine efficacy of WAg533 in possums was compared to BCG using three different methods of inoculation (conjunctival/intranasal, oral and sub-cutaneous) followed by aerosol challenge. Overall, WAg533 was a more potent vaccine than BCG and by two methods of inoculation gave more measures of protection that were significantly different from controls.