How are live vaccines generally administered?

Live vaccines are generally administered subcutaneously. This method allows the vaccine to be absorbed into the body effectively while stimulating the immune system appropriately. Subcutaneous administration is commonly used for vaccines because it can provoke a more robust immune response, which is often necessary for live attenuated vaccines.

While the other routes of administration have their specific uses in vaccination practices — intramuscular injections are commonly utilized for many inactivated vaccines, intravenous administration is less common due to its higher risk and specificity for certain therapies or conditions, and oral administration is used for a few vaccines (such as the oral polio vaccine) — subcutaneous delivery stands out as the preferred route for the majority of live vaccines. This route strikes a balance between ease of administration, comfort for the patient, and effective immune activation.