According to a World Organization report MMR Vaccine Appears to Confer Strong Protection from COVID-19: Few Deaths from SARS-CoV-2 in Highly Vaccinated Populations, nearly all countries with few or no deaths from COVID-19 have also had large measles-rubella vaccination programs in recent years.

The United Nations Office for the Coordination of Humanitarian Affairs reported that as of January 10, 2020, 82 percent of the population of American Samoa had been immunized with the MMR vaccine in response to a 2019 measles outbreak. The U.S. Department of the Interior provided funding to immunize the remaining eighteen percent of the population. The American Samoa has not had any COVID-19 cases, to date.

Large measles vaccination programs have occurred in many countries with few or no deaths from COVID-19. Madagascar, a country with a population of 27.5 million people, vaccinated 7.2 million  with measles-rubella containing vaccines in 2019. This was in addition to anyone previously vaccinated. Madagascar, like American Samoa, has had zero deaths from COVID-19.

Hong Kong is an example of a population which extended MMR vaccination campaigns to include many adults. A city with nearly the same population as New York City, and located just over 500 miles from Wuhan where the pandemic began, Hong Kong has seen only four COVID-19 deaths. By contrast, New York City has had 14,482 confirmed COVID-19 deaths and 5,313 probable COVID-19 deaths during the same period.

Under the theory of herd immunity, it is not necessary in any single population to vaccinate 100% of individuals to eliminate nearly all deaths from COVID-19. Instead, one has to only provide enough coverage so that the effective reproductive number (R) of the virus through each patient is less than 1, which stops the logarithmic progression. A drop in the R value below 1 likely explains why many populations with high MMR vaccination rates have reported so few deaths from COVID-19.

Principal investigator Jeff Gold discovered the correlation of MMR vaccination rates to COVID-19 death rates on March 18, 2020. Gold has since evaluated epidemiological data about MMR vaccination programs from dozens of countries, with each correlation verified by co-investigators William H. Baumgartl, MD, MSME, and Larry P. Tilley, Diplomate, ACVIM.

Gold’s MMR vaccine research was first published publicly on March 29, 2020, the same day his findings were forwarded to the National Institute of Health’s COVID-19 Research Team. Corroborating biological evidence was published twelve days later by a team of neuroscientists at the University of Cambridge in the United Kingdom, indicating that rubella is the component of the MMR vaccine active against COVID-19.