The first possible case of community spread of COVID-19 was reported by the CDC on Wednesday February 26, and the tone of information disseminated to the American public has taken a decidedly serious turn. What do we do now?
Over the last couple days, the number of new cases of COVID-19 in countries outside China have exceeded those reported in China, indicating a turning point in the outbreak. One might assume that means the quarantine measures in China were not effective, however, their large-scale quarantines actually gave the rest of the world weeks to prepare. Additionally, the decline in new cases in China is indicative that their efforts are quelling the spread of disease and suggest that similar measures may be helpful in other areas of the world.
Before moving on, let’s define a few terms useful for this discussion:
Travel-related or imported case – originating in the source area (ie. China) but found elsewhere due to travel
Local or secondary transmission – originating outside the source area, but traced back to a known case
Community transmission – originating outside the source area without tracing to a known case
Sustained community transmission – unrestricted spread of cases
3,664 cases of COVID-19 have been reported in 46 countries outside China as of today, February 28. Despite this global spread, the vast majority of cases around the world still represent imported and secondary cases. There are a few examples of small clusters of community transmission in Japan, Italy, Iran, and Korea, but WHO officials maintain that there is no evidence of sustained community transmission outside China at this point.
This week, a woman in California tested positive for COVID-19, which isn’t all that surprising except for the fact that she had no travel history or known risk of exposure. This represents the first possible case of community spread in the U.S. and exposes a key fear in the outbreak–that there are infected individuals walking among us potentially spreading COVID-19. How many undetected cases there are and how easily they can transmit infection are principal unknowns.
The CDC has defined a suspected case of COVID-19 as a patient with pneumonia and risk of exposure (either via travel or close contact with a known case). So far, these have been the only patients to be tested for the coronavirus that causes COVID-19. This definition does not identify asymptomatic or mild cases, which could represent up to 80% of total cases and may contribute to spread in the community. Further, the most recent patient wasn’t immediately tested for the novel coronavirus because she didn’t have any exposure risk, which delayed diagnosis and can also contribute to additional spread. In response, the CDC amended their testing criteria today (February 28) to include patients with unknown exposure risk.
Nancy Messonnier, director of the CDC’s National Center for Immunization and Respiratory Diseases thinks it’s no longer a question of if COVID-19 will spread across the U.S, but when. She’s urged American citizens to prepare for significant disruptions including school closures and for businesses to consider telecommuting options for their employees. The WHO maintains more positive messaging. WHO Director-General Dr. Tedros Adhanom Ghebreyesus stated on Thursday February 27 that for countries outside China, “the window of opportunity to contain [COVID-19] is now.”
The seasonality of many respiratory infections may also soon play a role in this outbreak. With cases of influenza and common cold (including those caused by other coronaviruses) about to subside as it becomes warmer in the northern hemisphere, it’s not unreasonable to think that COVID-19 will track with it. Though it’s possible that the southern hemisphere including regions of South America, Africa, and Australia may be at higher risk for community transmission of COVID-19 as they enter their autumn season. Notably, the 1918 influenza pandemic started in early 1918, was maintained rather quietly during the middle of the year, and exploded in cases and deaths in the 1918-1919 winter season. If the epidemiology of COVID-19 is similar, we could be in for the true global pandemic next winter.
As someone who endures anxiety, I am uncomfortable with ending this blog with the blanket statement that gets thrown around: Don’t panic! However, with whatever control you can manage, please try not to panic. Watch the situation closely (globally, here’s a great resource) and follow your state and local health departments for information in your area. If you’re traveling, check the CDC Travelers’ Health site before you go.
Other tips for staying healthy apply. Wash your hands often. Alcohol-based hand sanitizers maybe useful when out in public. Maintain cough etiquette and respiratory hygiene by sneezing and coughing into your arm or in a tissue that is then disposed. Don’t touch your face (I’m guilty of this, big time). Stay home when you’re sick. Clean commonly touched objects and surfaces at home, at work, and in your car. Take a call instead of a face-to-face with coworkers or clients who are ill. Maintain a distance of 1-2 meters (3-6 feet) with apparent sick people around you.
There’s no reason to stock up on food or consumables, but that may change. If you require medication, that might be the first thing to supply in the event of a stay-in-place order. Face masks are not necessary and are generally not helpful outside the healthcare setting, though they may be useful to protect others if you are sick. If you live in an area with sustained transmission and you require medical attention, call your healthcare provider for instructions.
You can certainly share concern, but be sure to share accurate information. If you are sick, remember that it is still far more likely to be something other than COVID-19.
More resources:
Five Myths About Coronavirus Debunked
CDC Coronavirus Disease 2019 (COVID-19)
STAT News – Coronavirus