WASHINGTON — The U.S. Department of Health and Human Services’ free COVID-19 test distribution program has allowed millions of households to get tests, delivered by mail, for the past several years.

Not everyone will be eligible for the vaccine under new restrictions, and vaccines will remain available at most pharmacies.

While holiday gatherings offer an opportunity to spread joy and happiness, they also offer the opportunity to spread any diseases that might currently be making the rounds. That can be especially ...