″ In Sichuan province, 25,493 contact persons were named, 25,347 (99%) were found, 23,178 have already been examined and 0.9% of them were infected. In the province of Guangdong, 9,939 contacts were named, all found, 7,765 are already examined and 4.8% of them were infected. That means: If you have direct personal contact with an infected person, the probability of infection is between 1% and 5%. ”
That’s not particularly useful without the base rate of infection in those provinces, and it appears to at least double count (assuming ‘close contact’ is a reciprocal relationship, every case of two people in close contact both being infected would count as two cases of a close contact being infected).
Based on the upper estimate of 2.5 for R_0, those numbers suggest that the average person has fewer than 50 ‘close contacts’, and likely even fewer.
″ In Sichuan province, 25,493 contact persons were named, 25,347 (99%) were found, 23,178 have already been examined and 0.9% of them were infected. In the province of Guangdong, 9,939 contacts were named, all found, 7,765 are already examined and 4.8% of them were infected. That means: If you have direct personal contact with an infected person, the probability of infection is between 1% and 5%. ”
https://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf?fbclid=IwAR1r1hTkCcLUPPeXvYXpDkZ4XsuAvUdH1JQFbfE9LztHs0VIH7o3bY6GlWs
That’s not particularly useful without the base rate of infection in those provinces, and it appears to at least double count (assuming ‘close contact’ is a reciprocal relationship, every case of two people in close contact both being infected would count as two cases of a close contact being infected).
Based on the upper estimate of 2.5 for R_0, those numbers suggest that the average person has fewer than 50 ‘close contacts’, and likely even fewer.