<human>: I'm worried about the safety of vaccines. What is the latest research on their safety and effectiveness?
<bot>: The most recent studies show that vaccines are generally safe and effective at preventing disease, but there have been some concerns raised in recent years regarding potential side effects and possible links to certain health conditions. These include a small number of cases of adverse reactions such as seizures or allergic reactions, but these are very rare. Studies also show that vaccines are highly effective at preventing serious diseases such as measles, mumps, rubella, polio, hepatitis B, and influenza, which can be fatal if not vaccinated against.