This message is intended for primary
care, urgent care, emergency, internal medicine, and infectious
distribute as appropriate.
There are a number of mumps outbreaks occurring
in the U.S., including one in LA County, which is predominately
among men who have sex with men (MSM).
Providers should consider the diagnosis of mumps
among patients presenting with parotitis, other salivary gland
swelling, and/or orchitis, even if patients have been
Ensure patients have completed the two dose
series of measles-mumps-rubella (MMR) vaccinations.
Mumps is highly
infectious and spreads through congregate living/social settings
causing sporadic outbreaks as has been demonstrated in recent
outbreaks in the U.S.
In LA County and
surrounding areas, there is currently a mumps outbreak involving over
40 patients. The majority of these cases are among MSM but some are
women and heterosexual men with social connections to MSM cases. Most
transmissions appear to have occurred at large venues such as
athletic clubs, bars, theaters and nightclubs. The majority of cases
have had no documentation of complete vaccination; however, some
cases were fully vaccinated.
Many of the LA
County mumps cases were initially misdiagnosed, most commonly as
salivary duct stones and lymphadenopathy. In addition, some
misdiagnoses occurred because of reliance on false negative IgM
below has been updated since the March 9, 2017 Health Alert “Mumps
Clusters in Adults in Los Angeles County”. Any significant new text
or recommendations are denoted in blue.
Requested of Providers
√ Consider mumps when evaluating any patient who has
acute orchitis, parotitis, or other salivary gland swelling [see
clinical presentation below].
about possible exposure to mumps in patients presenting with fever,
malaise, headache, anorexia, myalgia or non-specific respiratory
specimens for confirmation of diagnosis: buccal swab for PCR ideally
within three days but no greater than nine days after symptom onset
and blood for serology (IgM and IgG) four or more days after symptom
onset. Keep in mind that in vaccinated individuals the IgM may remain
negative [see specimen collection below].
suspect mumps patients that they should remain home and away from
public spaces such as school and work for five days after parotitis
onset or, in its absence, until the resolution of constitutional
report suspect cases without waiting for laboratory confirmation [see
reporting section below].
DPH Immunization Program with any questions about a potential mumps
case [see resources section below].
that all clinic staff who have contact with patients have immunity to
mumps (two documented doses of MMR or serologic evidence of
Unvaccinated individuals are
at highest risk for infection, though mumps should also be suspected
among vaccinated individuals. Mumps incubation period ranges from
12-25 days, but symptoms typically develop 16 to 18 days after
exposure to mumps virus.
Mumps typically begins with a
few days of fever, headache, myalgia, fatigue, and anorexia followed
by development of salivary gland swelling, pain and tenderness. Mumps
usually involves one or both parotid salivary glands but in 10% of
cases other salivary glands (submandibular and sublingual) are
symptomatic. In vaccinated patients, symptoms may be
is the most common complication and can occur without prior
presentation of parotitis/salivary gland swelling. Clinicians
should inquire about scrotal or testicular pain in men with fever and
other non-specific symptoms.Other complications
of mumps may include oophoritis and neurologic manifestations
(including meningitis, encephalitis, and deafness).
Specimen Collection and
Testing at Public Health Laboratory
The Public Health Laboratory
will transport and process all mumps specimens. Note: specimens will
not be processed until the suspect case has been reported to Public
Health [see reporting details below].
Specimens for Mumps Testing:
swab: A reverse-transcriptase polymerase chain
reaction (PCR) test of the parotid duct (buccal swab) is the
preferred method of confirming acute mumps infection. Optimal
timing for specimen collection is within three days of symptom
onset but specimens may be collected up to nine days. Massage
the salivary gland area for about 30 seconds and use a viral
culturette/synthetic swab to swab around the parotid duct. Place
the swab in 2-3 mls of liquid viral or universal transport
more days after symptom onset, test blood for
mumps IgM and IgG antibodies, as earlier tests may
be falsely negative. Serum IgM may be
absent or attenuated in previously vaccinated individuals. Draw 8-10 mL of
blood in a red top or serum separator tube; spin down serum if
In addition, submit a urine specimen in a sterile container for
supplemental mumps testing.
Call the Public Health
Laboratory courier to arrange for specimen pick-up weekdays 8:00am –
5:00pm: 562-658-1460. All specimens should be stored at 4ºC until
The turnaround time for
results can be up to 7-10 business days after receipt of specimens at
the Public Health Laboratory.
Transmission and Infection
Mumps is highly infectious and
is transmitted by contact with airborne respiratory secretions or
saliva or through fomites. A major factor
contributing to outbreaks of mumps is being in a crowded environment.
Also, certain behaviors that result in exchanging saliva, such as
kissing or sharing utensils, cups, lipstick or cigarettes, may
increase the spread of the virus.
Typically, mumps patients are
contagious from two days before through five days after onset of
parotitis. Suspected mumps cases should wear a mask and sit apart
from other patients (3-6 feet). Patients should be told to stay at
home and avoid public spaces for five days after the onset of parotid
swelling, or, if they do not have parotid swelling, until
constitutional symptoms have resolved.
vaccination with two doses of mumps-containing vaccine is the most
effective way to prevent disease. It is routinely recommended for all
children and is a requirement for school attendance. Adults
without proof of immunity should receive a two shot series.There is conjecture that an extra dose of MMR
vaccine in those previously vaccinated may limit the duration and
size of mumps outbreaks and may be considered for high risk
individuals during this outbreak.
of exposed individuals: DPH will assist in the management of all
suspect cases and their contacts. The management of contacts will be based on their exposure,
vaccination, and immune status. In general, if not
contraindicated, management may include an extra dose of MMR vaccine,
as noted above. Immune globulin is not indicated for
mumps post-exposure prophylaxis.
Mumps suspect cases should be
reported by telephone promptly to the local health department. Do not
wait for laboratory confirmation.
Los Angeles County DPH:
After 5 pm or on weekends:
Long Beach Health and Human
Weekdays 8:00 am to 5:00 pm:
After hours: 562-435-6711, ask
for the Communicable Disease Officer.
Pasadena Health Department:
Weekdays 8:00 am to 5:00 pm:
After hours: 626-744-6043.
or clinical assistance-contact LAC DPH Immunization Program’s
Surveillance Unit: Weekdays 8:00 am to 5:00 pm:
213-351-7800. After hours call: 213-974-1234.