 In addition to basic science investigations, Ramakrishnan, along with Marcel Behr and Paul Edelstein, reviewed studies concerning the concept of latent tuberculosis in order to determine whether tuberculosis-infected persons have life-long infection capable of causing disease at any future time.These studies, both published in the British Medical Journal (BMJ), show that the incubation period of tuberculosis is short, usually within months after infection, and very rarely more than 2 years after infection.They also show that more than 90% of people infected with "M. tuberculosis" for more than two years never develop tuberculosis even if their immune system is severely suppressed.