Vaccination FAQs (cont.)

Medical Author:
Medical Editor:

Are there different types of vaccines?

There are two major categories of vaccines.

  • The first category of vaccine is made from live viruses that have been "attenuated" or weakened so that they usually do not cause the disease (Table 2). In some cases, the vaccine itself does cause the disease. Usually, the disease caused by the vaccine is milder than the natural disease.
  • The second category of vaccine, inactivated vaccine, is produced by growing the bacterium or virus in culture and then inactivating it (killing it) by using heat or chemicals (Table 3). These vaccines cannot cause the disease but allow the body to develop immunity. While these vaccines are safer, they do not produce protection as good as that from the live vaccines. These vaccines require multiple doses and often require periodic supplementation.
Table 2: Live attenuated vaccines
Yellow fever
Intranasal influenza
Oral polio
Oral typhoid
Table 3: Inactivated (killed) vaccines
Polio shot
Hepatitis A
Hepatitis B
Influenza shot
Acellular pertussis
Human papillomavirus
Haemophilus influenza type b

Can people receive multiple vaccinations during one visit to the doctor?

Simultaneous administration (vaccines given at the same visit but not in the same shot) of most commonly used vaccines does not decrease the response to the vaccines or increase the risk for adverse reactions. The simultaneous administration of vaccines was instituted to increase compliance with recommended immunization schedules. If people have to come back many times to get additional shots, there is an increased chance that they will not get all recommended vaccinations. In children, there are now a few combination shots that contain multiple vaccines in a single shot. None of these are approved for use in adults except the one containing measles/mumps/rubella (MMR). There is an ongoing controversy about giving "too many" vaccines at one time to little children.

Medically Reviewed by a Doctor on 2/24/2014

Patient Comments

Viewers share their comments

Vaccinations - Indications Question: Have you followed the standard recommendations to vaccinate you or your children? Why or why not?
Vaccinations - Contraindications Question: Are you a person who has a condition that prevents you from being vaccinated? Please describe it.