What is the Seroconversion Rate of Mumps Vaccine?

A 16-month-old male came to the emergency room with a 2-3 day history of fever to 101° F. He had emesis 3 times over the first two days. His mother noted that he was somewhat fussier when eating but he had good oral intake and urine output. She also thought his left face was slightly swollen. There is documented mumps in his community and he was vaccinated with the measles-mumps-rubella vaccine (MMR) 1 month earlier. The past medical history, family history, and review of systems were negative. The pertinent physical exam revealed him to be afebrile with normal vital signs and growth. HEENT examination showed his pharynx to be minimally erythematous, and diffuse swelling along the lower left mandible. There was a 1 x 1 cm lymph node at the angle of the left mandible and diffuse cervical lymphadenopathy bilaterally. The rest of his physical examination was normal. The diagnosis of of presumed mumps was made. The work-up included serology for mumps IgM, urine culture, and parotid massage with oral culture. A rapid strep test was also negative. The family was sent home with instructions for mumps exposure, oral hygiene precautions, and symptomatic treatment. The patient’s clinical course over the next few days saw him without fever and a decrease in the facial swelling. One week later, the laboratory evaluation was positive for a urine IgM, but was negative for serum or oral culture.

Mumps is caused by a paramyxoviridae family virus and humans are the only known host. The spread is from infected respiratory tract secretions. Mumps causes swelling of one or more salivary glands, in particular the parotid glands. Up to 1/3 of patients do not have salivary swelling that is apparent. Parotitis in children is usually not due to mumps and can be caused by several other viruses including coxsackieviruses, cytomegalovirus, enteroviruruses, human immunodeficiency virus, and parainfluenza virus. It can also be causes by Staphlococcus aureus, mycobacterium (nontuberculous), cirrhosis, diabetes, drug reactions and malnutrition.

Mumps complications include central nervous system problems (including hearing problems, cerebellar ataxia, radiculitis), arthritis, myocarditis, mastitis, thyroiditis, myocarditis, oophoritis, orchitis (with rare sterility), and pancreatitis. Death is rare and infection in the first trimester of pregnancy is associated with an increased risk of spontaneous abortion. It does not appear to increase the risk of congenital malformations. Most cases are in children 5-15 years of age. Incubation is 16-18 days but can occur between 12-25 days after exposure. Highest infectivity is from 1-2 days before the parotid swelling to 5 days after the swelling, but the virus may be shed from 7 days before swelling to 9 days after.

In 2006, a resurgence occurred in the United States, with the highest attack rate among persons aged 18-24 years and 57% of patients had previously received 2 doses of vaccine. In 2007 and 2008, incidence declined but unfortunately another outbreak occurred in 2009, mainly among unimmunized or underimmunized populations.

Learning Point
Mumps vaccine is highly effective. Its effectiveness has been estimated at 73%-91% for 1 dose and 76%-95% for 2 doses. However these recent outbreaks may show that vaccine induced immunity may wane after > 10 years since the second dose of vaccine.

Recommendations for vaccination are that MMR be given at 12-15 months of age and again at 4-5 years of age. Recommendations for potentially susceptible individuals during an outbreak should be individualized based upon age and can be found from the Centers for Disease Control.

Questions for Further Discussion
1. What is the seroconversion rate for measles vaccination?
2. What is the seroconversion rate for hepatitis A vaccination?
3. What are the potential side effects of MMR vaccination?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Mumps and Immunization.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

American Academy of Pediatrics. Mumps, In Pickering LD, Baker CJ, Kimberlin DW, Long SS, eds. Red Book: 2009 Report of the Committee on Infectious Diseases. 28th edit. Elk Grove Village, IL: American Academy of Pediatrics; 2009;468-472.

Centers for Disease Control. Mumps Outbreak — New York, New Jersey, Quebec, 2009. MMWR. November 12, 2009 / 58(Dispatch);1-4
Available from the Internet at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d1112a1.htm?s_cid=mm58d1112a1_e (rev. 11/12/2009, cited 12/17/2009).

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effecively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    5. Patients and their families are counseled and educated.
    7. All medical and invasive procedures considered essential for the area of practice are competency performed.
    8. Health care services aimed at preventing health problems or maintaining health are provided.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Practice Based Learning and Improvement
    13. Information about other populations of patients, especially the larger population from which this patient is drawn, is obtained and used.


    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital