An exegesis on tuberculosis, a scourge that continues to threaten humanity: in 2015, there were 10.4 million new cases and 1.4 million deaths.
London-based microbiologist Lougheed left the TB field after years of drug research that yielded few results. Indeed, her text makes clear that Mycobacterium tuberculosis is a bug that has co-evolved with humans since the birth of our species, acquiring extraordinary survival strategies. When the bugs land in a lung, the immune system sends macrophages to engulf and eat them, but they convert the macrophages to squats and live on various immune cell lipids. In turn, these infested macrophages group into granulomas that cluster in the lung, each with its own ecology. Further complicating the problem of combatting the disease is the fact that M. tuberculosis has an especially thick cell wall. Antibiotics only work against actively growing cells, so if the TB bug is sleeping, it can persist and then become the source of reactivation of a latent infection. Then there are the bugs with mutations that have resulted in multiply drug-resistant TB. Lougheed examines all these microbe–immune system interactions by dissecting current research papers as though readers were part of a weekly session of post-doctoral candidates keeping up-to-date. (The book could have used further editing for a general audience.) The author also explains the need for daily treatment regimens of multiple pills or injections that can last for years. As Lougheed notes, as well, TB flourishes in the presence of poverty, malnutrition, crowded living conditions, and co-infections. Unfortunately, this makes certain areas particularly vulnerable to the disease, including migrant and refugee camps.
Not just a medical history, but a call to action. TB is not some quaint 19th-century romantic tragedy but rather a very real and present danger that requires investments in diagnostics and new drugs and greater attention to social and racial inequities.