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Study: Omicron has shorter incubation than other COVID-19 strains

A new study suggests that with the evolution of mutant strains, the mean incubation period of COVID-19 decreased gradually from five days for cases caused by the Alpha variant to 3.42 days for the Omicron variant.



22 August (UPI) – According to a recent study, the mean COVID-19 incubation period gradually decreased as mutant strains evolved, going from five days for cases brought on by the Alpha variant to 3.42 days for the Omicron variant.

According to the study, COVID’s Beta and Delta versions were in the middle of the pack at 4.5 and 4.41 days, respectively.

The researchers, who are headquartered in China, stressed the significance of determining the incubation time of various COVID-19 variations in order to estimate how long people need remain isolated in order to prevent the virus from spreading.

They said that by better preventing the spread of COVID-19, their research could aid in modifying prevention and control measures.

The study’s results were released on Monday in JAMA Network Open.

The study’s findings “indicate that SARS-CoV-2 has developed and mutated continually during the COVID-19 pandemic, yielding variants with different improved transmission and pathogenicity,” the researchers wrote.

They stated that it is still challenging to stop COVID-19 dissemination. Over the course of the ongoing epidemic, it had caused more than 460 million confirmed cases and 6 million fatalities globally by the month of March.

The study, which comprised a review of 142 papers involving 8,112 patients, also discovered variations in incubation times because of patient age and sickness severity.

People over the age of 60 saw a mean COVID-19 incubation of 7.43 days, whereas individuals under the age of 18 experienced a mean incubation of 8.82 days.

Patients with light to moderate illnesses experienced it for 6.99 days, whereas those with severe illnesses had it for 6.69 days.

The researchers pointed out that numerous experiments have been carried out all around the world to determine the typical COVID-19 incubation duration.

But they added that “the reported estimates of incubation period in these fragmented investigations vary depending on the number of research participants recruited, the type of design used, the data collection period, and the nation of the study.”

They said that the current COVID-19 incubation period differs from that of the initial Wuhan outbreak due to the spread of the Delta and Omicron strains.

The COVID-19 symptoms might show up two to 14 days after a person is infected to the virus, according to the Centers for Disease Control and Prevention.

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