Medicine (MD/DO)
Live Attenuated Vaccines

Master Live Attenuated Vaccines with Picmonic for Medicine

With Picmonic, facts become pictures. We've taken what the science shows - image mnemonics work - but we've boosted the effectiveness by building and associating memorable characters, interesting audio stories, and built-in quizzing.

Live Attenuated Vaccines

Recommended Picmonics

picmonic thumbnail
Pediatric Vaccinations - Age 2 Months
picmonic thumbnail
Pediatric Vaccinations - Age 4 Months
picmonic thumbnail
Pediatric Vaccinations - Age 6 Months
picmonic thumbnail
Pediatric Vaccinations - Age 12 to 15 Months
picmonic thumbnail
Pediatric Vaccinations Age 4-6 Years

Live Attenuated Vaccines

Live-sign Vaccine-syringes
Live attenuated vaccines are weakened versions of the virus against which the patient is being vaccinated. They are reduced in virulence, but still viable and therefore "live". These viruses or bacteria are attenuated, or weakened, in a laboratory, usually by repeated culturing. They induce both humoral and cell-mediated immunity but on rare occasion may revert to virulent strains, which is why in general they should not be given to immunocompromised patients. Live attenuated vaccines produce immunity in most recipients with one dose, except those administered orally. Examples of these vaccines include varicella (chickenpox), zoster, (shingles), polio (Sabin), smallpox, yellow fever, influenza (intranasal), MMR, rotavirus, typhoid fever, and BCG.
Humoral and Cellular Immune Response
Hummer-in-Moon and Basketball and Tennis Ball

Live attenuated vaccines induce humoral/antibody-mediated and cell-mediated components of the immune system. They do this via activation of T and B cells. T cells become activated when the live virus is inoculated into the host and enters various cell types. The associated proteins are proteolysed within the cell and presented via MHC-I to circulating T-cells. B cells become activated when circulating dendritic cells phagocytose the viral vaccine and present the antigens via MHC-II to plasma cells, leading to their maturation into memory B-cells.

May Revert to Virulent Form
Devil Standing in Corner

Theoretically, live attenuated vaccines could revert to their virulent form, causing infectious symptoms in the host. Immunocompromised patients are especially susceptible to this. Currently, the only live attenuated vaccine known to actually do this is the oral polio (Sabin) vaccine.

Do Not Require Boosters
No-Sign over Rocket Booster

Live attenuated vaccines generally do not require boosters as they induce memory B-cells to produce circulating antibodies, providing a much longer-lasting immunity.

Varicella (Chickenpox)
Varsity-Zorro Chicken-box

The Varicella zoster virus (VZV) vaccine for chickenpox is a live attenuated vaccine often given to children.

Zoster (Shingles)
Zorro Shingles

There are currently two vaccines for shingles - Zostavax and Shingrix. The older one, Zostavax, is a live attenuated vaccine and can be given to healthy adults over age 60 to prevent shingles. Zostavax is contraindicated in immunosuppressed patients. The newer one, Shingrix, is much more effective and is a recombinant vaccine indicated for adults over age 50 regardless of whether they had chickenpox.

Polio (Sabin)
Saber-Polo Player with Pill

The Sabin polio vaccine is a live-attenuated virus. It was administered orally but is no longer available in the United States.

Small Fox

The vaccine for smallpox is a live-attenuated vaccine. It is not routinely administered.

Yellow Fever
Yellow Fever Beaver

The vaccine for yellow fever is a live-attenuated vaccine.

Influenza (Intranasal)
Flute-Virus with Nose

The intranasal influenza vaccine is a live-attenuated vaccine.

M&M-aRt Syringe

The vaccine for measles, mumps, and rubella (MMR) is a live-attenuated vaccine. It is the only live attenuated vaccine that can be given to AIDS patients given its safety profile.


The vaccine for rotavirus is a live attenuated vaccine. It is unique in that it is first given at 6 weeks of age when most live attenuated vaccines are not given until 9 months of age.

Typhoid Fever (Oral)
Typhoon Fever-beaver

There are several vaccines for typhoid fever, caused by Salmonella typhi. The oral vaccine (Ty21a) is a live attenuated vaccine.

BCG (Bacillus Calmette-Guérin)

Previously used for tuberculosis, the BCG vaccine is no longer administered for this purpose. Instead, it is used in certain urological malignancy treatments.


Take the Live Attenuated Vaccines Quiz

Picmonic's rapid review multiple-choice quiz allows you to assess your knowledge.

It's worth every penny

Our Story Mnemonics Increase Mastery and Retention

Memorize facts with phonetic mnemonics

Unforgettable characters with concise but impactful videos (2-4 min each)

Memorize facts with phonetic mnemonics

Ace Your Medicine (MD/DO) Classes & Exams with Picmonic:

Over 1,890,000 students use Picmonic’s picture mnemonics to improve knowledge, retention, and exam performance.

Choose the #1 Medicine (MD/DO) student study app.

Picmonic for Medicine (MD/DO) covers information that is relevant to your entire Medicine (MD/DO) education. Whether you’re studying for your classes or getting ready to conquer the USMLE Step 1, USMLE Step 2 CK, COMLEX Level 1, or COMLEX Level 2, we’re here to help.

Works better than traditional Medicine (MD/DO) flashcards.

Research shows that students who use Picmonic see a 331% improvement in memory retention and a 50% improvement in test scores.