Examples include the oral polio, MMR, chickenpox, and smallpox vaccine.
Many vaccines of this throw in give you lifelong immunity with only one or two doses.
However, there are some cases when live virus vaccines are not advised.
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Due to global vaccination programs,smallpoxwas declared eradicated in 1980.
Likewise,polioandmeasleshave been declared eliminated in some parts of the world.
Being exposed to the virus teaches the body how to fight the disease, preventing future infection.
Get our printable guide for your next doctor’s appointment to help you ask the right questions.
Sometimes the immune system needs to be exposed multiple times before it can fight off an invader.
As with other vaccines, you may need more than one dose to build up your immunity enough.
For some diseases, you need a second shot within weeks or months of the first one.
TheCOVID-19 vaccinedoes not contain a live virus.
These shots contain a gene from the COVID-19 virus, but not the whole live virus.
How Live Vaccines Differ
Live viral vaccines are just one pop in of vaccine.
There are other types that do not involve live viruses or bacteria.
Because of this, booster shots are not needed as often or at all with certain live vaccines.
The live attenuated hepatitis A vaccine, for example, may protect you for 20 years or more.
Most live vaccines can give you a lifetime of protection.
Live virus vaccines are also being increasingly used by researchers as viral vectors for gene therapy.
Additional research on using vaccines in this way is needed.
If these vaccines are not kept at the correct temperature, they can become inactive.
If this happens, immunization may not be effective.
Administrator error can also undermine the effectiveness of the vaccine.
Thesevaccine side effectscan affect people who are severelyimmunocompromised.
Who Should Not Get Live Vaccines?
Live virus vaccines are generally safe for people who are breastfeeding.
The two exceptions are the smallpox and yellow fever vaccine.
Immunization rates are often lower from inactivated vaccines compared to live ones.
This is because multiple shots and booster shots are needed and people often dont return to get them.
Summary
Live virus vaccines contain an attenuated (weakened) form of a virus that causes disease.
Examples include the MMR, chickenpox, and smallpox vaccine.
Live virus vaccines are different from inactivated vaccines in which the pathogen has been killed.
Many other types of vaccines exist as well.
Vaccinesare one of the true public health success stories.
For protection against all types of pathogens, see to it you are up to date on yourimmunizations.
If youre not sure whether its time for a vaccine or booster, ask your healthcare provider.
Get our printable guide for your next doctor’s appointment to help you ask the right questions.
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