Vaccine and Infectious Disease Division

Calculating the good

In global health research, many new tools and interventions are developed in the hopes of decreasing or eliminating devastating diseases.  Now, mathematical analyses reveal just how much good these novel approaches can do if implemented.

In a recent study, VIDI member Dr. Elizabeth Halloran and colleagues model the effects of novel tuberculosis (TB) interventions currently being developed with support from the Bill and Melinda Gates Foundation, focusing on Southeast Asia.  Looking at the potential implementation of the portfolio of new diagnostic tools, drugs and vaccines, either alone or in combination, the authors find that the potential reductions in TB incidence by 2050 associated with use of these tools will range from  13 to 71 percent by 2050.

The 11 countries defined by the World Health Organization as the Southeast Asia region– Bangladesh, Bhutan, Democratic People’s Republic of Korea, India, Indonesia, Maldives, Myanmar, Nepal, Sri Lanka, Thailand and Timor-Leste – account for approximately a third of the world’s TB cases and TB-related deaths, and have existing TB intervention programs which could potentially utilize the novel interventions.

Using a mathematical model that takes into account aging and death of population members, the researchers looked at various TB treatments and tools separately and in combination, to examine their potential effects on TB over the next four decades.  With no new interventions in place, more than 100 million new TB cases and nearly 18 million TB-related deaths are expected by 2050.  The authors also explored the potential incidence reductions associated with other interventions and strategies. Using a combination of novel diagnostic tools, treatment regimens and mass vaccinations could prevent 78 million TB cases and 14 million deaths by 2050.  These mathematical analyses indicate that techniques under development to combat TB may not eliminate the disease, but would lead to a significant reduction in the burden and mortality it causes.  Additional technologies and delivery strategies may have an even greater impact. -RT

Epidemiological benefits of more-effective tuberculosis vaccines, drugs, and diagnostics.  Abu-Raddad LJ, Sabatelli L, Achterberg JT, Sugimoto JD, Longini IM Jr, Dye C, Halloran ME.  Proc Natl Acad Sci U S A. 2009 Aug 18;106(33):13980-5.