[Editor’s Note: This editorial was co-authored by Jim Connolly, president and CEO of Rockville, MD-based Aeras]
Extensively drug-resistant tuberculosis (XDR-TB) is more prevalent than experts realized and continues to infect new victims, according to a recent study in The Lancet. Even in the best health care settings, these tuberculosis strains are incredibly difficult to cure, requiring expensive and toxic treatments that take patients years to complete and can cause side effects as severe as temporary psychosis or permanent hearing loss.
Focused on eight countries, the new study only hints at the scope of the global problem. Nearly 80 countries have reported cases of tuberculosis that are resistant to most drugs, and some have discovered TB strains that are virtually untreatable. Many of the countries with the highest burdens of TB lack the tools needed to diagnose complex drug-resistant disease – so this may be the tip of the iceberg. The situation is alarming.
This news may not surprise Seattle residents, considering in some ways King County fares no better. In 2011, 17 percent of King County patients diagnosed with active tuberculosis showed resistance to at least one front-line drug. Last year we learned of the first county resident to be diagnosed with multidrug-resistant tuberculosis (MDR-TB)—a form of the disease that requires treatment with toxic drugs for 18-24 months, including a period of isolation, and can cost as much as $250,000 to treat a single case. TB rates in King County are among the highest in the U.S. and reflect the global and mobile nature of our community.
Of course, the scale of the problem in Washington State and the U.S.—which had 10,500 cases last year—does not begin to approach that in many other countries.
Globally, nine million people have active TB, spread when a person coughs, laughs, or simply speaks. In many densely populated parts of Asia, Africa and Eastern Europe, TB is devastating. In an age where the most remote places in the world are just a plane ride away, no one is immune. London now has the highest TB rate of any capital city in Western Europe. It is a global epidemic.
TB today is everyone’s problem, and global problems demand global solutions.
Most of the tools used to fight TB are outdated. The only existing vaccine, called BCG, was introduced 90 years ago when movies were still silent and DNA was unknown. While useful in preventing severe cases of TB in infants, its protection wanes during adolescence and provides no protection against TB in adults. We will not eliminate the TB epidemic without new vaccines.
After decades of research, the global health community is now at a historic point in vaccine development. The number of TB vaccines in clinical trials has grown from zero in 2001 to 14 today.
This work is being driven by scientific innovation and unconventional partnerships. Our two nonprofit organizations—the Seattle-based Infectious Disease Research Institute (IDRI) and the Washington, D.C.-based Aeras—recently joined forces on a promising TB vaccine candidate, originally developed at IDRI, that entered its first Phase I clinical trial in August. The vaccine candidate, ID93 + GLA-SE, targets both active TB disease and latent TB, which lays dormant in one-third of the world’s population and can progress to active disease when the immune system is compromised.
The global health research community must build on the growing momentum of TB research to produce breakthrough vaccines, drugs and diagnostic tools, particularly given the growing threat of multi-drug resistant TB. To do this, they will require increased investment in this research. Ultimately, only with new TB vaccines will we have a chance to end the global epidemic of this disease and protect our mobile, cosmopolitan citizenry.