We understand that there is a lot of conflicting information available regarding the safety of vaccines. At Express Healthcare LLC, we believe in the proven and rigorously tested safety and efficacy of vaccinations. Every vaccine doctors use to protect their patients have undergone extensive trials and testing to ensure they work as designed. The most common side effects of receiving a vaccination is some redness, bruising, or soreness at the site of the injection. If this happens, the effects will typically dissipate within a few hours following the administration of the vaccine injection.