Delta viral load 1,000 times higher than original virus

Chinese researchers tracking a recent COVID-19 outbreak in China found that people infected with the Delta variant carry 1,260 times more virus in their noses compared to those infected in the first wave of the pandemic.

The higher load means the virus spreads far more easily from person to person, increasing infections and hospitalizations, they reported ahead of peer review in a paper first posted on medRxiv earlier in July and updated on Friday.

The interval between when people were exposed to infected individuals and when they themselves were diagnosed decreased from an average of 6 days in 2020 to 4 days during the Delta outbreak, the researchers found.

The Delta variant is "outcompeting all other viruses because it just spreads so much more efficiently," said Shane Crotty of the La Jolla Institute for Immunology in San Diego, who was not involved in the Chinese study.

In the United States, Delta accounts for about 83% of new infections, with unvaccinated people representing nearly 97% of severe cases. -- Reuters