https://edition.cnn.com/2020/05/03/health/coronavirus-vaccine-never-developed-intl/index.html
https://www.theguardian.com/world/2020/apr/18/dont-bet-on-vaccine-to-protect-us-from-covid-19-says-world-health-expert
https://www.telegraph.co.uk/global-health/science-and-disease/vaccine-news-covid-19-coronavirus-trials-uk/
https://www.wired.co.uk/article/coronavirus-vaccine-development
https://www.businessinsider.com/coronavirus-vaccine-may-be-impossible-to-produce-scientists-covid-2020-4?r=US&IR=T
https://www.statnews.com/2020/05/06/mounting-promises-on-covid-vaccines/
https://nymag.com/intelligencer/2020/04/will-there-be-a-coronavirus-vaccine-maybe-not.html
https://www.timesnownews.com/health/article/what-would-happen-if-a-covid-19-vaccine-is-never-developed/586588
https://www.worldometers.info/coronavirus/
https://www.publichealth.org/public-awareness/understanding-vaccines/vaccines-work/