People with mild or asymptomatic COVID-19 cases may be just as infectious as those with severe cases who require hospitalization, a study published May 25 in Science found.
A team led by researchers in Berlin analyzed data on 25,381 COVID-19 samples collected in Germany between Feb. 24, 2020, and April 2. Of these cases, 9,519 involved hospitalizations, and 1,533 involved infections from the B.1.1.7 variant first found in the U.K. They analyzed viral load for each sample and used the results to estimate infectiousness levels.
Five study findings:
1. Only 8 percent of patients had high viral loads, which suggests greater infectiousness.
2. Of these individuals with high viral loads, about one-third either had no symptoms or had mild symptoms.
3. Overall, viral loads were lowest among children and increased with age.
4. Laboratory-based estimates of infectivity were 2.6 times higher for people infected with the U.K. variant compared to those infected with other virus strains.
5. Patients with mild or no symptoms had higher viral loads at the time of their first positive COVID-19 sample, compared to hospitalized patients for ages up to 70 years.
To view the full study, click here.