COVID-19

COVID-19 Roundup: Isolation Period Recommendations, Symptom Duration

CDC Changes Isolation Period1

Due to mounting evidence that the majority of patients are no longer contagious 10 days after the appearance of symptoms, the CDC is now encouraging ending isolation using a symptom-based strategy, rather than relying on negative results of a second COVID-19 test.

They recommend:

  • For most persons with COVID-19 illness, isolation and precautions can generally be discontinued 10 days after symptom onset and resolution of fever for at least 24 hours, without the use of fever-reducing medications, and with improvement of other symptoms.
  • For persons who never develop symptoms, isolation and other precautions can be discontinued 10 days after the date of their first positive RT-PCR test for SARS-CoV-2 RNA.

Symptom Duration2

In a recent study conducted by the CDC, 35% of 270 patients surveyed had not yet fully recovered 2 to 3 weeks after positive test results. When broken down by age group, 26% of those aged 18-34 years, 32% of those aged 35-49 years, and 47% of those aged 50 years and older reported not having returned to their normal health within 2 to 3 weeks after testing.

The presence of chronic conditions further impacted these rates. However, 1 in 5 previously healthy patients aged 18-35 had not returned to normal health at 3 weeks.

Vitamin D Levels3

According to the results of a recent study, low vitamin D plasma levels appears to be an independent risk factor for COVID-19 infection and hospitalization.

For their study, the researchers examined data from an Israeli cohort of 782 patients with and 7,025 patients without COVID-19. Low plasma vitamin D was defined as concentrations below 30 ng/mL. Other factors influencing the risk of infection included age of 50 years, male gender, and low-medium socioeconomic status. 

COVID-19 Updates from CDC4

As of July 24, 2020, the CDC has received reports of a total of 28,745,587specimens tested for SARS-CoV-2, of which, 2,762,464 (9.6%) were positive.

Levels of influenza-like illness (ILI) are low, but high for the time of year. Although levels of COVID-19-like illness and confirmed cases have decreased since the previous week, various regional shifts in rates have occurred, with areas previously seeing high levels beginning to decrease while other areas begin to increase.

Overall, the cumulative COVID-19-associated hospitalization rate is 120.9 per 100,000. Rates are highest among individuals aged 65 years and older (338.2 per 100,000) and those aged 50-64 years (182.3 per 100,000). Weekly hospitalization rates have increased over the last 3 weeks.

Percentages of deaths attributed to pneumonia, influenza, or COVID-19 increased from week 26 to week 28, which is the first time this number has increased since mid-April. While the percentage for week 29 is currently 9.1%, this number is expected to increase as more death certificates are processed.

—Michael Potts

References:

  1. Centers for Disease Control and Prevention. Duration of isolation and precautions for adults with COVID-19. https://www.cdc.gov/coronavirus/2019-ncov/hcp/duration-isolation.html. Updated July 22, 2020. Accessed July 27, 2020.
  2. Tenforde MW, Kim SS, Lindsell CJ, et al. 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. Published online July 24, 2020. MMWR Morb Mortal Wkly Rep. doi:10.15585/mmwr.mm6930e1
  3. Merzon E, Tworowski D, Gorohovski A, et al. Low plasma 25(OH) vitamin D level is associated with increased risk of COVID‐19 infection: an Israeli population‐based study. Published online July 23, 2020. FEBS. doi:10.1111/febs.15495
  4. COVIDView: a weekly surveillance summary of US COVID-19 Activity. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/covid-data/covidview/index.html. Updated July 17, 2020. Accessed July 20, 2020.