Vaccines should be mandatory because they have been proven to be safe and effective. The US Department of Health and Human Services maintains that vaccines are among the safest medical products available to the public. Because vaccines are given to millions of healthy people, including children, they are held to very high safety and efficacy standards. Any licensed vaccine is rigorously tested across multiple phases of trials before it is approved for use and it is continuously monitored. Testing and evaluation by institutions like the Food and Drug Administration and recommendations from institutions like the CDC ensure that only clinically tested and sade vaccines are made available for widespread public use.  Vaccines should and can be mandated because the public can be assured that their vaccinations are safe and functional.
Vaccines should not be mandatory because even those that are deemed “safe” can do harm. For instance, vaccines contain harmful ingredients. Aluminum is used in some vaccines, and excess aluminum in human bodies can cause neurological harm. Glutaraldehyde, a compound used to disinfect medical and dental equipment, is used in some DTaP vaccinations and exposure can cause asthma and other respiratory issues. Some flu vaccines contain cetyltrimethylammonium bromide (CTMB), a compound used as an antiseptic, which can be a skin, eye, and respiratory irritant. The list goes on and on. Vaccines can be deemed safe for distribution and use even when they are made up of ingredients that can do minor to severe damage to damage to an individual's health.