Information and FAQs About a Recent Vaccine Refrigeration Issue


Peninsula Pediatrics

For Release: October 5, 2015

Peninsula Pediatrics, part of Stanford Medicine Children’s Health, is one of Northern California’s most dedicated and passionate providers of care for infants, children and teens. We have been serving Bay Area families for generations, and we have a great reputation for quality and patient safety.

On September 21, the San Mateo location of Peninsula Pediatrics discovered a temperature malfunction in a refrigerator where childhood vaccines are stored. Additionally, the team found opportunities for improvement related to the quality control processes in the storage and monitoring of these vaccines. An immediate investigation began.

As a result, and in an abundance of caution, 1551 families have been contacted in order to provide free re-vaccinations for their children. This is because the affected vaccines, though not harmful, may have lost potency due to temperature variations, thus providing less immunity than expected.

To date, there is no evidence of any patient harm. The refrigerator, which went in service January 14, has been replaced, and enhanced quality control safeguards have been instituted, including enhanced processes for monitoring. We regret the stress and inconvenience this event has created.

Our organization and care teams care deeply about all of our patients and their families, and want to ensure their trust and safety while in our care.

Frequently Asked Questions (FAQs)

  1. Which vaccines were possibly affected?
    1. Dtap (diphtheria, tetanus, and pertussis (whooping cough)) and Tdap (tetanus, diphtheria, and pertussis)
    2. IPV (Polio)
    3. Pentacel (Diphtheria,Tetanus, Pertussis, Haemophilus influenzae type b, and Polio)
    4. Menactra (meningococcus (meningitis))
    5. Hepatitis A and Hepatitis B
    6. HPV (human papillomavirus) – except doses given 9/10/15 – 9/21/15
    7. PCV (pneumococcal)
    8. Influenza (flu)
  2. Is there any potential harm to my child in receiving one of the vaccines stored outside the recommended temperature?
    • No, there is no harm to your child.
  3. What dates are dates of vaccination that need to be repeated?
    • We are providing free revaccinations for immunizations administered between January 14, 2015 and noon on September 21, 2015.
  4. Is there any harm to my child in being revaccinated?
    • No, there is no additional risk in being revaccinated beyond the usual risks associated with that specific vaccine. In fact, in this situation, revaccination is recommended by the Advisory Committee on Immunization Practices and other experts.
  5. If the vaccination is a series, does my child have to start the series all over again?
    • No they just need to be revaccinated for the doses related to this incident.
  6. What actions have you taken to respond to this event and prevent this in the future?
    • Peninsula Pediatrics immediately implemented remedial action including the purchase of a replacement refrigerator, electronic monitoring, systems improvement and employee corrective action.

For more information, call (650) 342-4145.

About Stanford Medicine Children's Health

Stanford Medicine Children’s Health, with Lucile Packard Children’s Hospital Stanford at its center, is the Bay Area’s largest health care system exclusively dedicated to children and expectant mothers. Our network of care includes more than 65 locations across Northern California and more than 85 locations in the U.S. Western region. Along with Stanford Health Care and the Stanford School of Medicine, we are part of Stanford Medicine, an ecosystem harnessing the potential of biomedicine through collaborative research, education, and clinical care to improve health outcomes around the world. We are a nonprofit organization committed to supporting the community through meaningful outreach programs and services and providing necessary medical care to families, regardless of their ability to pay. Discover more at

About Stanford University School of Medicine

The Stanford University School of Medicine consistently ranks among the nation’s top medical schools, integrating research, medical education, patient care and community service. For more news about the school, please visit The medical school is part of Stanford Medicine, which includes Stanford Health Care and Stanford Medicine Children’s Health. For information about all three, please visit