Slow Recovery From Mild COVID-19: A 2020 Survey of Outpatients

Summary

• Little was known about how outpatients with milder COVID-19 recover.
• In a multistate telephone survey of adults who tested positive as outpatients and had symptoms, 35% had not returned to their usual health when interviewed 2–3 weeks after testing.
• Even among 18- to 34-year-olds with no chronic conditions, 1 in 5 had not recovered.
• COVID-19 can mean prolonged illness even for young, healthy adults, and public health messages should reach them.

The survey

The Influenza Vaccine Effectiveness in the Critically Ill (IVY) Network — 14 mostly urban academic health systems in 13 states — listed adults who tested positive by RT-PCR from March 31 to June 4, 2020. A random sample of those tested as outpatients (in clinics, or in emergency departments without admission) was interviewed by CDC staff by phone 14–21 days after testing, from April 15 to June 25, in several languages. They were asked about background, chronic conditions, symptoms at testing, whether those had cleared, and: "Would you say that you are feeling back to your usual health?"

Of 582 people called, 325 completed interviews. After exclusions — proxies answering, earlier positive tests, missing answers — 292 remained, and the 274 (94%) who had symptoms at testing were analyzed.

Who they were: median age 42.5; 52% women; 36% Hispanic, 35% non-Hispanic White, 18% non-Hispanic Black; 53% had at least one chronic condition. They had felt unwell a median of 3 days before testing and were interviewed a median of 16 days after. 7% were later hospitalized.

Recovery

65% had returned to usual health, a median of 7 days after testing; 35% had not.

After adjustment, slower recovery was linked to age 50+ (vs 18–34), three or more chronic conditions, obesity and a psychiatric condition (mainly anxiety or depression) — each with more than twice the odds. Race and ethnicity were not linked to recovery, though the sample was modest.

Symptoms

Respondents reported a median of seven of the 17 symptoms asked about — most often fatigue (71%), cough (61%) and headache (61%). Fever and chills had cleared in almost everyone (97% and 96%). The most persistent:

• cough — still present in 43%;
• fatigue — 35%;
• shortness of breath — 29%.

Symptoms that did clear took a median of 4 to 8 days from testing, longest for loss of smell and taste (8 days each). And 34% of those who said they were back to usual health still had at least one symptom.

Symptoms at testing and those unresolved 14–21 days later. Figure from the CDC report.

What it means

Most earlier studies looked at hospitalized patients. This one shows that even outpatients may take weeks to recover — about a third weren't back to normal in 2–3 weeks, where more than 90% of outpatients with influenza recover within about 2 weeks. Slow recovery can mean long absences from work, school and other activities, even for young adults. The link with psychiatric conditions needs more study.

Limits: people who didn't respond may have differed — the sickest, if hospitalized, may not have answered; symptoms that ended before testing or began after weren't recorded; and answers relied on memory.

The message: COVID-19 can be prolonged even when mild, so messages should reach people who may not see it as serious — including young adults and those without chronic conditions. Social distancing, frequent handwashing and consistent, correct use of face coverings in public should be strongly encouraged.

Sources

Based on Mark W. Tenforde, Sara S. Kim, Christopher J. Lindsell and others, with the IVY Network Investigators and the CDC COVID-19 Response Team, "Symptom Duration and Risk Factors for Delayed Return to Usual Health Among Outpatients with COVID-19 in a Multistate Health Care Systems Network — United States, March–June 2020," MMWR, Centers for Disease Control and Prevention (Early Release, July 24, 2020); a work of the United States government in the public domain. The report's social-media text card is not reproduced.