Hi!
This question can be approached in different ways.
For one, technically, it cannot prevent people from getting sick, but it can certainly help people who are sick and have health issues.
Some people earn too much money to be eligible for Medicaid (a healthcare program for people who don't make enough money) but earn to little to afford it on their own. Having universal health care would allow everyone to have access to healthcare - doesn't matter their financial status. This would also help (help, not completely prevent) prevent people from getting sick and getting health issues.
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