8. Conclusions

Animal and human health is intimately interwoven and food animals serve as a reservoir of diseases of public health significance [74]. Animals with a contagious disease remain in the population and serve as a reservoir of infection for other animals and human beings. Therefore, the development of vaccines for animals against bovine tuberculosis is highly effective for TB control or development of recombinant BCG with expressing luciferase activity can be used as the most effective tool to advance drug development. The screening of TB in human or animal population is a very time-consuming process as Mycobacterium grows very slowly; conventional drug screening takes more than 3 weeks and the biosafety level-3 (BSL-3) facility is the basic requirement. Therefore, it is the need of an hour to develop rapid diagnostic procedures which can detect the organism within a short period of time. Some successful efforts are being made for the development of a new screening method to identify TB drug candidates by utilizing luciferase-expressing recombinant Mycobacterium bovis bacillus Calmette-Guéren (rBCG) [75].

The risk due to zoonotic TB is significantly less in developed countries than developing countries, which is due to the milk pasteurization and effective bovine tuberculosis control programs. Therefore, food safety of animal-origin food is worth considering. Efforts to improve food safety include scaling up the heat treatment of milk and ante-mortem and postmortem inspection of all animals entering the food chain which will not only reduce the risk of transmission but also bring substantial benefits for the control of other foodborne diseases. A healthier animal population leads to healthier food supply along with economic benefits and improvements in animal welfare. The epidemiology of bovine TB is well understood and effective control and elimination strategies have been known for a long time but the disease is still widely distributed and often neglected in most developing countries. The increase of this disease in such areas calls for stronger intersectoral collaboration between the medical and veterinary professions to assess and evaluate the scale of the problem, mostly when zoonotic TB could represent a significant risk. Developed countries which follow test-and-slaughter policies still are not able to completely eliminate infection in cattle because of wild animal reservoirs; therefore, they are now focusing on the wild animal vaccination. Therefore, the vaccine research and development program should be taken into account for possible application of vaccines to the animals, particularly in developing countries. Disease surveillance programs especially in areas where risk factors are present in animals and humans should be considered as a priority.
