DPH Investigating Mumps Outbreak Among School-Age Children in New Castle County

DOVER – The Delaware Division of Public Health (DPH) is investigating an outbreak of mumps cases among school-age children in New Castle County. As of March 3, 2020, DPH had identified nine cases of mumps as part of this outbreak, including seven confirmed cases and two probable cases. The confirmed cases involve five individuals at William Penn High School, one individual at George Read Middle School, both within the Colonial School District; and one individual at St. Georges Technical High School within the New Castle County Vo-Tech School District. No additional information about those individuals will be provided to protect personal health information.

DPH has been coordinating closely with the impacted schools and school districts since cases were first identified to provide guidance for limiting the spread of illness and to identify any other potential cases. The schools notified their communities of the positive cases and potential exposure to mumps, and provided recommended guidance to families.

DPH advises any student or any member of the household who has symptoms or develops symptoms should be kept at home. In addition, it is recommended that parents of children who may have been exposed to mumps contact their child’s primary care provider. Children with suspected or confirmed mumps should stay home for five days after the onset of parotitis (gland swelling), or as directed by their primary care provider.

Mumps is an acute viral infection spread through saliva or mucus from the mouth, nose, or throat. An infected person can spread the virus by coughing, sneezing, or talking, sharing items, such as cups or eating utensils, with others, and touching objects or surfaces with unwashed hands that are then touched by others. The Centers for Disease Control and Prevention (CDC) notes that a substantial increase in the number of mumps outbreaks and outbreak-associated cases have occurred in the United States since late 2015.

The symptoms of mumps include fever, headache, body aches, loss of appetite and swelling of parotid salivary gland(s) — glands on the insides of the cheeks, floor of the mouth, and under the tongue. Mumps symptoms could develop from 12 days to 25 days after exposure. As an ongoing preventive measure, it is recommended that individuals follow good hand washing practices. Parents are encouraged to review the immunization records for their children and make sure they are up to date on recommended vaccines, including the Measles, Mumps and Rubella (MMR) vaccine, and to contact their child’s primary care provider with any questions.

Some people who get mumps have very mild or no symptoms, and often they do not know they have the disease. Most people with mumps recover completely in a few weeks. However, mumps can occasionally cause complications, especially in adults. Complications can include:

  • inflammation of the testicles (orchitis) in males who have reached puberty; rarely does this lead to fertility problems
  • inflammation of the brain (encephalitis)
  • inflammation of the tissue covering the brain and spinal cord (meningitis)
  • inflammation of the ovaries (oophoritis) and/or breast tissue (mastitis)
  • deafness

The CDC recommends children get two doses of MMR vaccine, starting with the first dose at 12 to 15 months of age, and the second dose at 4 to 6 years of age. Teens and adults who did not get the recommended MMR vaccines per the above schedule should be vaccinated so they are up to date.

It is possible for someone to get the mumps even after they have been vaccinated, however, that is not to say the mumps vaccine is ineffective. MMR vaccine is safe and effective. A person with two doses of MMR vaccine has about an 88% reduction in risk for mumps; a person with one dose has a 78% reduction in risk for mumps. In addition, disease symptoms are milder and complications are less frequent in vaccinated people. Also, high vaccination coverage helps to limit the size, duration, and spread of mumps outbreaks, therefore it is still very important to be up to date on MMR vaccine.

Individuals with questions should contact their primary care provider or the Division of Public Health at 1-888-295-5156 or visit https://www.cdc.gov/mumps/index.html.

Mumps is a reportable disease in Delaware. Health care providers should promptly report suspected cases of mumps, and confirmed cases, to the DPH Office of Infectious Disease Epidemiology (OIDE) at 302-744-4990 (normal business hours) or 1-888-295-5156 (outside of normal business hours), fax to 302-223-1540, or email reportdisease@delaware.gov. Providers are asked not to wait for laboratory test results to return before reporting.


A person who is deaf, hard-of-hearing, deaf-blind or speech-disabled can call the DPH phone number above by using TTY services. Dial 7-1-1 or 800-232-5460 to type your conversation to a relay operator, who reads your conversation to a hearing person at DPH. The relay operator types the hearing person’s spoken words back to the TTY user. To learn more about TTY availability in Delaware, visit http://delawarerelay.com.

The Delaware Department of Health and Social Services is committed to improving the quality of the lives of Delaware’s citizens by promoting health and well-being, fostering self-sufficiency, and protecting vulnerable populations. DPH, a division of DHSS, urges Delawareans to make healthier choices with the 5-2-1 Almost None campaign: eat 5 or more fruits and vegetables each day, have no more than 2 hours of recreational screen time each day (includes TV, computer, gaming), get 1 or more hours of physical activity each day, and drink almost no sugary beverages.