The plague is back, and this time it’s not thanks to far-voyaging ships or caravans traversing some distant trade routes, but to corn. This disease, caused by one of man’s oldest bacterial foes, Yersinia pestis, and spread by flea-infested rodents, is often overlooked in modern times in favor of more headline-grabbing epidemics like Ebola, HIV, and antibiotic-resistant STDs. But the plague has always kept close quarters with mankind and continues to surprise us with its adaptability. Historically, the plague has long been associated with poor hygiene, cramped living situations, and substandard housing, with outbreaks blooming in the cities that make such fine homes to hordes of the rodent vectors. Yersinia has, for the most part, lost its edge in our modern society thanks to widespread advancements in urban hygiene and sanitation. Good housing and sound infrastructure largely bar the entry of rodents into our homes, hindering human exposure to microbe-bearing fleas. But the plague is a tenacious enemy, and its dynamics have changed to counter these hygienic advancements. As I wrote a few years ago, Yersinia has established an endemic presence in the African continent, where cases of the infection comprise over 97% of the world’s 20,000-odd cases in the past fifteen years. Plague is a major public health concern throughout the continent, but particularly so in east Africa’s Tanzania, where outbreaks have been pulsing through the region in time with the cycle of the seasons since 1980. Since then, the country has tallied just under 9,000 cases and 675 deaths due to plague outbreaks.