Coronavirus is only the latest iteration of an age-old human affliction. Even now, with the benefit of advanced medical science, our reaction – our confusion, our fear – is not so different from how our ancestors experienced recurrent and terrifying onslaughts of plague, cholera, and yellow fever across the ages. We can learn from the courage and ingenuity of those who travelled this road before us.
 
Consider the work of Dr. Carlos Finlay in Cuba. In 1880 he hypothesized, and then worked to prove his hypothesis, that yellow fever, a disease that regularly decimated coastal populations up and down the Americas, was spread by infected mosquitos. Those mosquitos came to our shores in the 17th century on African slave ships and attacked portal communities in the tropics as well as cities like New Orleans and Philadelphia. The resulting epidemics occurred with oppressive regularity in the summer months, to the people's great dread, with mortality rates as high as 50 percent. The impact was tremendous – not only in the milllions of lives lost and the wretchedness this caused, but in economic gains and opportunities wiped out or delayed (the Panama Canal).
 
Connecting the transmission of the deadly virus to its source or vector was a decisive step forward in the long struggle against yellow fever. It preceded the development of a vaccine by more than 60 years. Here's how it happened: A young doctor, Carlos Finlay, returned to his home in Havana one night, exhausted, after caring for a Carmelite priest dying of yellow fever. Realizing he had forgotten to say his daily rosary, he sat in his armchair, sweating in the oppressive heat, fingering his beads and swatting at a bothersome mosquito. Suddenly, inspiration pierced his depression and weariness: Could the mosquito, like the one annoying him that moment, be transmitting the infection from person to person? If so, this was marvelous. One could not fight the brutal steamy summer air – the miasma – but one could fight mosquitos.
 
Inspiration, however, was not enough to proceed. Courage and even heroism would be needed to prove Finlay's hypothesis. These were at hand, thanks to 57 young Jesuit priests and brothers who volunteered as experimental subjects. As each arrived from Spain to staff the Colegio de Belen, newly founded by Queen Isabel II of Spain, he was met by Finlay, carrying a test tube filled with mosquitos that had just fed on a patient sick with yellow fever. Taking their lives in their hands, these Jesuits allowed themselves to be bitten for the sake of their fellow human beings. Three died of the bite, but all 57 were willing to do the same.
 
Subsequent experiments supported Finlay's hypothesis. Although a vaccine to definitively eradicate the disease would not come for decades, Finlay's insight helped man to co-exist safely with yellow fever until that time. The incidence of yellow fever in Cuba dropped precipitously through mosquito control. Standing water, a breeding ground for the noxious pests, was eliminated where possible or treated aggressively with insecticides where not. Panama, where tens of thousands of workers had already died of the disease while building the canal followed Cuba's lead. The last Panama Canal worker to die of yellow fever came in 1906.
 
There are important lessons for us here -- first and foremost, lessons in resourcefulness and valor. 
 
Already, thousands of human minds are, today, tenaciously working to find a solution to Covid-19. They're persisting without respite, persisting through depression and fatigue, to find a way forward. Just as Dr. Finlay did.
 
And, you can depend on it, inspiration is sure to strike again.
 
You can also see today the same kind of valor that animated the Jesuit volunteers who let the infected mosquitos bite them. You see it in the countless men and women who keep showing up for work at nursing homes or crowded food production lines. Their examples help us all to keep up and increase our courage so we can join them as we ease back into our normal daily lives.
 
As we face the moment when we too realize that we have no choice but to go back out into the world of work and personal interactions, we can take hope from contemplating our predecessors' success in confronting yellow fever. Like us, they dreamed of a vaccine. But they didn't lock themselves away until it was developed. They found a way to steel themselves and then to steal the deadly efficiency away from the virus that plagued them. A century later, we can do the same.