The ongoing mumps outbreak at Temple University in Philadelphia has led to an unusually high number of requests for mumps testing. In order to reduce the burden on our laboratory resources, and to optimize the utility of these tests, the DOH is requesting that clinicians refrain from testing where the test is unlikely to yield meaningful results:
- Mumps testing should not be ordered for patients without symptoms of mumps.
- Mumps IgM is unlikely to be positive if done too early in the course of the disease (i.e., ≤3 days from onset of illness).
- Urine testing is unlikely to be helpful in the absence of genitourinary involvement (orchitis or oorphoritis).
- Cases that meet the probable case definition and that are linked to a known outbreak generally do not need to be tested for mumps. Consultation with the DOH or your local health department is recommended in these instances.
The Centers for Disease Control and Prevention (CDC) have the following recommendations for ensuring effective and efficient mumps testing during outbreaks:
At the onset of a suspected mumps outbreak, patients suspected to have mumps should be tested by RT-qPCR to confirm mumps and rule out other possible etiologies. However, once a mumps outbreak is confirmed, jurisdictions should consider alternate strategies to ensure more efficient use of testing resources.
One strategy is to consider limiting testing of patients who meet the probable mumps case definition when resources are constrained or testing volume is unusually high. The Council of State and Territorial Epidemiologists (CSTE) case definition for mumps defines a probable case as:
Acute parotitis or other salivary gland swelling lasting at least 2 days, or orchitis or oophoritis unexplained by another more likely diagnosis, in:
- A person with a positive test for serum anti-mumps immunoglobulin M (IgM) antibody, OR
- A person with epidemiologic linkage to another probable or confirmed case or linkage to a group/community defined by public health during an outbreak of mumps.
Consider limiting testing of probable cases when resources are constrained or testing volume is unusually high.
During an outbreak, jurisdictions’ communication with providers should define the specific groups or communities that are considered epidemiologically linked to the outbreak and which therefore may not require testing in a public health laboratory. Jurisdictions can use the Provider Testing Job-Aid as a tool to communicate this information to providers.
In certain situations, even epidemiologically linked cases warrant testing. These include:
- Patients with complications such as oophoritis, orchitis, aseptic meningitis, encephalitis, hearing loss, mastitis, or pancreatitis
- Patients who received ≥3 doses of measles, mumps, and rubella vaccine (MMR) more than 28 days before symptom onset
- Patients with recurrent parotitis (test samples from both occurrences when possible)
- Patients who traveled during their incubation period (12–25 days prior to onset), especially those with international travel
- CDC Mumps Information for Healthcare Providers: https://www.cdc.gov/mumps/hcp.html
- CDC Recommendation of the Advisory Committee on Immunization Practices for Use of a Third Dose of Mumps Virus–Containing Vaccine in Persons at Increased Risk for Mumps During an Outbreak: https://www.cdc.gov/mmwr/volumes/67/wr/mm6701a7.htm
- DOH Mumps Fact Sheet: https://www.health.pa.gov/topics/Documents/Diseases%20and%20Conditions/Mumps.pdf
- CDC Mumps Testing Job Aid for Clinicians Download Here
- Contact the Pennsylvania Department of Health (DOH) at 1-877-PA-HEALTH (1-877-724-3258) or your local health department to report the suspected case.
Originally released by the Pennsylvania Department of Health on 04/10/2019.