Tuesday, March 10, 2020

Coronavirus disease 2019: updates and resources

- Kenny Lin, MD, MPH

There's a bedtime folktale that I've read countless times to each of my four children called One Grain of Rice. If you aren't familiar with it, it is the story of a raja who lived "long ago in India" and hoarded his people's excess rice production for years, supposedly as insurance against a famine, but when the famine arrives, he refuses to open the royal storehouses. A clever "village girl" named Rani happens to catch a small amount of rice that trickles from a basket on the way from a royal storehouse to the palace. She goes to the palace to give it back, and is told by the grateful raja that he will give her any reward she desires for returning what belongs to him. She asks him for a single grain of rice. The raja protests that he can do much better than that.

"Very well," said Rani. "If it pleases Your Highness, you may reward me in this way. Today, you will give me a single grain of rice. Then, each day for thirty days you will give me double the rice you gave me the day before. Thus, tomorrow you will give me two grains of rice, the next day four grains of rice, and so on for thirty days."

"This seems to be a modest reward," said the raja. "But you shall have it."


It's clear that the raja had never seriously studied math or exponential growth. The illustrated version that we have includes colorful images of ever-larger baskets and, eventually, giant bags of rice as the days go by and the doubling continues. By the 30th day, it takes 256 elephants to make the final delivery of 536,870,912 grains of rice, for a grand total of more than one billion. The analogy here, of course, is that while the American "raja" pats himself on the back that there have only been (as of March 10) 647 cases and 25 deaths from COVID-19 in the U.S., we're almost exactly where Italy found itself two weeks ago, and where China was on Jan. 22. Today all of Italy is under an effective quarantine, and more than 3,000 have perished from COVID-19 in China.

Exponential spread of an infectious disease epidemic doesn't go on forever, of course. At some point, the virus runs out of hosts, or people are too far apart for it to easily find the uninfected. But if the peak of the epidemic curve exceeds the surplus capacity of our health care system (and as others have pointed out, it's not like hospitals maintain thousands of empty intensive care unit beds just waiting for an epidemic to strike), then more people will die, as health care professionals fall ill or succumb to exhaustion and there aren't enough resources for the critically ill to go around. That's why it's so important to start social distancing now, and to cancel or postpone mass gatherings such as conferences, concerts, political rallies, and athletic events - including March Madness.

Covid-19-curves-graphic-social-v3

To keep clinicians up-to-date on the evolving epidemic, the U.S. Centers for Disease Control and Prevention (CDC) has posted a comprehensive collection of resources for health care professionals who encounter patients with suspected SARS-CoV-2, including an assessment flowchart and interim management guidance for patients with confirmed infection. The American Academy of Family Physicians has an updated web page containing resources for coding, clinical management, communication, and patient education. Forward-thinking family physicians can also consult a Family Practice Management (now FPM) article for tips on on preparing your office for an infectious disease epidemic. Key points highlighted in this article include:

- Begin planning now.
- Master the detection, prevention and management of seasonal influenza and community-acquired pneumonia.
- Practice scrupulous infection control - "wash in and wash out."
- Communicate at all levels, and coordinate with public health agencies.
- Focus on staff management and business continuity.

The good news: we know a lot more now about the epidemiologic characteristics and clinical course of COVID-19, thanks to a recent analysis of more than 70,000 cases from the Chinese CDC. The mean incubation period appears to be around 5 days, and nearly all persons who develop symptoms doing so within 2 weeks of infection. Public health experts are calling for states and communities to update earlier preparedness plans and to ready hospitals and clinics to respond to the expected surge in respiratory illnesses. And after what can be fairly described as a national fiasco, it appears that reliable diagnostic testing for the novel coronavirus should soon be widely available in the U.S. To paraphrase NASA flight controller Gene Kranz during the ill-fated Apollo 13 mission, this crisis still has the potential to be public health's finest hour.