A recent study shows young adults are the biggest spreaders of COVID-19. A research team at Imperial College in London looked at cell phone location data of more than 10 million people. Their report was published in the journal Science.

They estimate those ages 35 to 49 make up over 40 per cent of new transmission through August of 2020. And young adults ages 20 to 34 made up another 35 per cent. They said children and older adults accounted for very little spread.

Researchers say to help slow the spread of the virus vaccinations should be focused on these two groups.

"This study provides evidence that the resurgent COVID-19 epidemics in the US in 2020 have been driven by adults aged 20-49, and in particular adults aged 35-49, before and after school reopening," the team wrote in their report, published in the journal Science.

"Unlike pandemic flu, these adults accounted after school reopening in October, 2020 for an estimated 72.2% of SARS-CoV-2 infections in the US locations considered, whereas less than 5% originated from children aged 0-9 and less than 10% from teens aged 10-19."

And it might be the adults aged 35 to 49 who are the biggest factor in driving the pandemic, as opposed to younger adults, Oliver Ratmann of the Imperial College COVID-19 Response Team and colleagues concluded.

"Prior to the implementation of COVID-19 interventions, contacts concentrated among individuals of similar age, were highest among school-aged children and teens, and also common between children/teens and their parents, and middle-aged adults and the elderly. Since the beginning of the pandemic, these contact patterns have changed substantially," the team wrote.

"This study indicates that in locations where novel highly transmissible SARS-CoV-2 lineages have not yet established, additional interventions among adults aged 20-49, such as mass vaccination with transmission-blocking vaccines, could bring resurgent COVID-19 epidemics under control and avert deaths," they added.

They estimated that people 35 to 49 accounted for 41% of the new transmissions through mid-August, and adults 20 to 34 were responsible for another 35%. Children and teens accounted for just 6% of spread. People 50 to 64 made up 15% of transmission.

"Over time, the share of age groups among reported deaths has been remarkably constant, suggesting that young adults are unlikely to have been the primary source of resurgent epidemics since summer 2020, and that instead changes in mobility and behavior among the broader group of adults aged 20-49 underlie resurgent COVID-19 in the US in 2020," the team wrote.

Story Source: Journal Science