60% may already have Immunity to COVID-19

This article talks about the presence of immunity against COVID-19 in as much as 60% of the population, even if they have not been exposed to the SARS-CoV-2 virus. There are 7 types of human coronaviruses or HCoV. Four of them are common. The 229E, NL63, OC43, and HKU1. The other two, MERS and SARS,…