[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Immunology](https://durgical.com/en/immunology/) › [Vaccines](https://durgical.com/en/immunology/#a-vaccines) › Live vaccines: who should not receive them

[Immunology](https://durgical.com/en/immunology/) · [Vaccines](https://durgical.com/en/immunology/#a-vaccines)

# Live vaccines: who should not receive them

- Topic

Live vaccines carry a weakened germ. With very weak defences or in pregnancy they can be dangerous, so they have clear contraindications.

Updated 2026-11-01

**See it in 3D:** [Thymus](https://durgical.com/en/anatomy/thymus/)

## Key points

- Live vaccines contraindicated in severe immunodeficiency and pregnancy.
- Rotavirus: not in SCID or after intussusception.
- Yellow fever: not before 6 months or with thymus disease.
- Living with an immunosuppressed person does NOT contraindicate vaccinating the contact.
- Recent immune globulin or blood interferes with MMR and varicella.

## What it is

A contraindication is a condition that raises the risk of a serious reaction, and the vaccine is not given; a precaution means weighing benefit against risk. Live attenuated vaccines can replicate unchecked when the immune system is badly compromised, and they carry a theoretical risk to the fetus. Knowing who must not receive them, and who can even when it seems otherwise, is a frequent exam question.

## Key facts

- General contraindication: prior anaphylaxis to the vaccine or one of its components (applies to all vaccines).
- Severe immunodeficiency: combined primary immunodeficiencies, leukemia, lymphoma, generalized cancer, recent chemotherapy or radiotherapy and prolonged high-dose corticosteroids.
- After chemotherapy or radiotherapy stops, wait at least 3 months before a live vaccine.
- Pregnancy: MMR and varicella are not given; avoiding pregnancy for one month after receiving them is advised.
- Rotavirus: contraindicated in severe combined immunodeficiency (SCID) and after a history of intussusception.
- Yellow fever: not given under 6 months of age or with thymus disease; in pregnancy only when exposure cannot be avoided.
- HIV: MMR and varicella can be given to children without severe immunosuppression (CD4 at least 15 %).

## Common situations and live vaccines

| Situation | Live vaccine? | Comment |
| --- | --- | --- |
| Severe combined immunodeficiency (SCID) | No | Risk of disseminated infection by the vaccine strain; includes rotavirus and BCG |
| Pregnancy | No | Theoretical fetal risk; inactivated influenza and pertussis vaccines are given |
| Prolonged high-dose corticosteroids | No, while they last | Wait until immunity recovers |
| HIV without severe immunosuppression | MMR and varicella yes | Decided by CD4; BCG is not given to infants with HIV |
| Immunosuppressed or pregnant household member | Yes | The vaccinated contact shields the vulnerable person |
| Egg allergy | MMR yes | Yellow fever does require assessing severe egg allergy |

## Clinical notes

- Not contraindications: living with an immunosuppressed or pregnant person, mild illness with or without fever, antibiotic use, penicillin allergy, or egg allergy for MMR.
- Recent antibody-containing blood products or immune globulin can cancel MMR and varicella; an interval set by the product is kept.
- Two injected live vaccines are given on the same day or at least 4 weeks apart.
- Moderate or severe acute illness is a precaution: the vaccine is postponed, not cancelled.

## Memory aid

Live vaccines skip the womb and the empty fortress (no immune defenders); the rest of the household gets vaccinated to build the wall.

## Test yourself

Think of the answer, then tap the question to see it.

## What two specific contraindications does the rotavirus vaccine have?

Severe combined immunodeficiency (SCID) and a history of intussusception.

## Can MMR be given to the child of a mother on chemotherapy?

Yes. Living with an immunosuppressed person does not contraindicate live vaccines; vaccinating the child protects the mother.

## Why can a recent transfusion make the measles vaccine fail?

Transferred antibodies neutralize the vaccine virus before it replicates, so no active immunity develops.

## Which history contraindicates the yellow fever vaccine at any age?

Thymus disease (for example thymoma, or thymectomy for that reason), as well as prior anaphylaxis to its components.

[Add to my cards (4)](https://durgical.app/estudiar/?add=/en/immunology/live-vaccines-who-should-not-receive-them/)

## See it in 3D

The structures of Durgical's 3D anatomy where it is found.

- [Thymus](https://durgical.com/en/anatomy/thymus/)

## Related

- [Vaccine types: live, inactivated, subunit, toxoid, mRNA, vector](https://durgical.com/en/immunology/vaccine-types-live-inactivated-subunit-toxoid-mrna-vector/)
- [Passive immunization: immunoglobulins and antitoxins](https://durgical.com/en/immunology/passive-immunization-immunoglobulins-and-antitoxins/)
- [Colombia's PAI schedule (which vaccines, at what age)](https://durgical.com/en/immunology/colombia-s-pai-schedule/)
- [Flow cytometry and the CD4 count](https://durgical.com/en/immunology/flow-cytometry-and-the-cd4-count/)
- [T-cell and combined deficiencies: DiGeorge, SCID, Wiskott–Aldrich, ataxia-telangiectasia](https://durgical.com/en/immunology/t-cell-and-combined-deficiencies-digeorge-scid-wiskott-aldrich-ataxia-telangiect/)
- [Secondary immunodeficiency: HIV, malnutrition, drugs, asplenia](https://durgical.com/en/immunology/secondary-immunodeficiency-hiv-malnutrition-drugs-asplenia/)
- [Thymus: where T cells learn](https://durgical.com/en/immunology/thymus-where-t-cells-learn/)

## Related conditions

- [Intussusception (children)](https://durgical.com/en/conditions/intussusception/)
- [HIV infection and AIDS](https://durgical.com/en/conditions/hiv-infection-and-aids/)
- [Anaphylaxis](https://durgical.com/en/conditions/anaphylaxis/)

## Microorganisms

- [Measles virus](https://durgical.com/en/microbiology/measles-virus/)
- [Varicella-zoster virus](https://durgical.com/en/microbiology/varicella-zoster-virus/)
- [Rotavirus](https://durgical.com/en/microbiology/rotavirus/)
- [Yellow fever virus](https://durgical.com/en/microbiology/yellow-fever-virus/)
- [Mycobacterium tuberculosis](https://durgical.com/en/microbiology/mycobacterium-tuberculosis/)

[← All of immunology](https://durgical.com/en/immunology/)

Educational content on the immune system; not a treatment or individual vaccination guide and no substitute for a health professional's advice. No doses are given.

Sources: [Contraindications and Precautions](https://www.cdc.gov/vaccines/hcp/imz-best-practices/contraindications-precautions.html) (Centers for Disease Control and Prevention (CDC), 2024); [Chapter 2: General Best Practice Guidance for Immunization | Pink Book | CDC](https://www.cdc.gov/pinkbook/hcp/table-of-contents/chapter-2-general-best-practice-guidance.html) (Centers for Disease Control and Prevention (CDC), 2021); [¿Cómo funcionan las vacunas?](https://vacunacion.minsalud.gov.co/Vacunas/Paginas/como-funcionan-las-vacunas.aspx) (Ministerio de Salud y Protección Social de Colombia, 2026).

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Representative model, for educational purposes only.

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Source: https://durgical.com/en/immunology/live-vaccines-who-should-not-receive-them/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/immunology/live-vaccines-who-should-not-receive-them/