The world’s largest study reveals who are the real “superdistributors” of coronavirus

But in addition, children and young people, experts have discovered, play a more important role in the spread of the virus, especially between homes, than previously thought, according to an article published in a specialized publication on September 30. “Sciences” published by scientists from the United States and India.

Researchers from the Princeton Institute for the Environment, Johns Hopkins University, and the University of California, Berkeley, in collaboration with health officials from India’s Tamil Nafu and Andra Pradesh states, analyzed 575,000 people. 71 people with a connection to 84 thousand. In 965 confirmed cases of COVID-19 (caused by SARS-CoV-2), the route of infection and mortality. This is the largest study in the world to date, in addition to contact with a new coronavirus, but also with other communicable diseases (a process that identifies people who have been in contact with an infected person).

Ramanam Laxminarayan, a Princeton University Environment researcher who led the groundbreaking study, said the work revealed the importance of so-called “superdistributors” for the spread of SARS-CoV-2, a small percentage of infected people who are highly effective in transmitting the virus. Experts found that 71 percent. of those infected did not infect their contacts, and only 8 percent. responsible for 60% of those infected. new infections.

“Our study is the largest empirical evidence of the role of superdistributors in the context of infectious diseases. It turns out that the existence of superdistributors in the context of COVID-19 can be described not as an exception, but as a rule, both in India as in other affected areas ”, explains R. Laxminarayan.

The evidence obtained by scientists provides a lot of valuable insights into the spread and mortality of COVID-19 in a country like India, where the disease has already killed 96,000 people. people, which is a very sad number for resource-deprived populations, scientists emphasize. Experts found that coronavirus-related deaths in India generally occur an average of six days after a patient is hospitalized (in the United States, an average of 13 days).

Furthermore, coronavirus deaths in India are concentrated in the 50-64 age group (compared to the United States, where deaths are highest in the United States).

The researchers also say they have the first large-scale evidence that the introduction of quarantine in India has significantly reduced the spread of the virus.

It has been found that the probability that a person infected with the new coronavirus (regardless of age) can be infected varies from 2.6 percent. in the community up to 9 percent. in the same home. The researchers found that children and youth (they account for a third of all COVID-19 cases) are critical to the spread of the virus (in the communities studied).

“Children are very effective distributors in such conditions, and no research has addressed this in the past. We have found that virus incidence and mortality are concentrated in a younger age group than we expected, based on country research. richer, ”says Laxminarayan.

Children and young people who support the study are at higher risk of contracting coronavirus from people their age. People of all ages are at higher risk of getting sick people. Overall, the chances of becoming infected with the new coronavirus range from 4.7 percent. for low-risk contacts up to 10.7 percent. high-risk contacts.

The study “Epidemiology and Dynamics of COVID-19 Transmission in Two States of India” was published in Science on September 30. The National Science Foundation and the Centers for Disease Control and Prevention contributed to the work.

This is not the first study to reach such conclusions. An earlier Hong Kong contact tracing report found that only 20% of people with COVID-19 were responsible for 80% of new infections, and up to 70% of infected people were no longer transmitting the virus to anyone.

Additionally, a case study conducted in May by the US Centers for Disease Control and Prevention found that at least 52 people became infected during a choir rehearsal, likely from a single follower.