Koronan leviämiseen liittyen superlevittäjät ja leviäminen keskittymissä (klusterit) on ollut esillä viimeaikoina myös (kuten myös @Tartsa :n postaamassa Hesarin uutisessa oli).
Miksi toiset levittävät tautia nopeammin/enemmän kuin toiset (super-levittäjät) ja miksi Covid19-virus leviää pienemmissä keskittymissä (klusterit) esim. SARS/MERS -nähden?
Estimates of k for SARS-CoV-2 vary. In January, Julien Riou and Christian Althaus at the University of Bern simulated the epidemic in China for different combinations of R and k and compared the outcomes with what had actually taken place. They concludedthat k for COVID-19 is somewhat higher than for SARS and MERS. That seems about right, says Gabriel Leung, a modeler at the University of Hong Kong. “I don’t think this is quite like SARS or MERS, where we observed very large superspreading clusters,” Leung says. “But we are certainly seeing a lot of concentrated clusters where a small proportion of people are responsible for a large proportion of infections.” But in a recent preprint, Adam Kucharski of LSHTM estimated that k for COVID-19 is as low as 0.1. “Probably about 10% of cases lead to 80% of the spread,” Kucharski says.
…
If k is really 0.1, then most chains of infection die out by themselves and SARS-CoV-2 needs to be introduced undetected into a new country at least four times to have an even chance of establishing itself, Kucharski says. If the Chinese epidemic was a big fire that sent sparks flying around the world, most of the sparks simply fizzled out.
https://wellcomeopenresearch.org/articles/5-67
Edit.
Science -lehden jutun kirjoittajan twiitti: