People infected with the delta variant of the novel coronavirus may be carrying more than a thousand times more virus particles and may test positive two days earlier than those infected with the original SARS-CoV-2, according to an early new study. The study has not been peer reviewed and looked at only a small number of cases in China, but if the results can be confirmed, they may explain, at least in part, why the delta variant is so much more infectious.
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The most “striking” aspect of this report was that it takes a much shorter time from being exposed to the delta variant to showing significant levels of virus, said John Connor, a researcher at Boston University’s National Emerging Infectious Diseases Laboratories who was not involved in the study. That changes the “window” of when people are infectious, Connor told Live Science.
“Knowing when an infected person can spread viruses is essential for designing intervention strategies to break chains of transmission,” [researchers wrote.] In other words, contact tracing would have to work more quickly to stop people from transmitting delta.