Speaking of Rubella, and only because it is one target of the MMR vaccine, there was at least one study has showed...I specifically said Rubella, a danger to the unborn if a pregnant woman is exposed. I have family of childbearing age that I would not want them exposed to Rubella.
"There was a significant inverse correlation (rs = −0.71, P < 0.001) between mumps virus titers (mumps titers) and COVID-19 severity..."
Stating further...
"COVID-19 has presented various paradoxes that, if understood better, may provide clues to controlling the pandemic, even before a COVID-19 vaccine is widely available. First, young children are largely spared from severe disease. Second, numerous countries have COVID-19 death rates that are as low as 1% of the death rates of other countries. Third, many people, despite prolonged close contact with someone who is COVID-19 positive, never test positive themselves. Fourth, nearly half of people who test positive for COVID-19 are asymptomatic. Some researchers have theorized that the measles-mumps-rubella (MMR) vaccine may be responsible for these disparities."
"Analysis of Measles-Mumps-Rubella (MMR) Titers of Recovered COVID-19 Patients | mBio" https://mbio.asm.org/content/11/6/e...s-rubella (,previously vaccinated with MMR II.