The state of Iowa has been experiencing a large mumps outbreak that began in December 2005
(1). As of April 10, 2006, a total of 515 possible mumps cases have been reported to the Iowa Department of Public Health (IDPH) during 2006
(2). This outbreak has spread across Iowa, and mumps activity, possibly linked to the Iowa outbreak, is under investigation in
six neighboring states, including Illinois (n = four), Kansas (n = 33), Minnesota (n = one), Missouri (n = four), Nebraska (n
= 43), and Wisconsin (n = four) (CDC, unpublished data, April 10, 2006). The reasons for this outbreak are
Mumps is an acute viral infection characterized by a nonspecific prodrome, including myalgia, anorexia, malaise,
headache, and fever, followed by acute onset of unilateral or bilateral tender swelling of parotid or other salivary glands
(2). An estimated 60%--70% of mumps infections produce typical acute parotitis
(3). Approximately 20% of infections are
asymptomatic, and nearly 50% are associated with nonspecific or primarily respiratory symptoms.
Complications include orchitis, oophoritis, or mastitis (inflammation of the testicles, ovaries, or breasts, respectively),
meningitis/encephalitis, spontaneous abortion, and deafness. Transmission occurs by direct contact with respiratory droplets or
saliva. The incubation period is 14--18 days (range: 14--25 days) from exposure to onset of symptoms. The infectious period is from 3 days
before symptom onset until 9 days after onset of
IDPH has identified two persons who had mumps diagnosed and were potentially infectious during travel on nine
different commercial flights involving two airlines during March 26--April 2, 2006. The commercial airline flights identified with
a potentially infectious traveler are listed below by date, carrier, and flight number:
Northwest Airline (NWA) flights:
March 26 NWA (Mesaba) #3025 from Waterloo, Iowa to Minneapolis, Minnesota
March 26 NWA #760 from Minneapolis, Minnesota, to Detroit, Michigan
March 27 NWA #0260 from Detroit, Michigan, to
Washington, DC--Reagan National
March 29 NWA #1705 from Washington, DC--Reagan National to Minneapolis, Minnesota
March 29 NWA (Mesaba) #3026 from Minneapolis, Minnesota, to Waterloo, Iowa
American Airline (AA) flights:
April 2 AA #1216 from Tucson, Arizona, to Dallas, Texas (DFW)
April 2 AA #3617 from DFW to Lafayette, Arkansas (Northwest Arkansas Regional [NAR])
April 2 AA #5399 from NAR to St. Louis, Missouri
April 2 AA #5498 from St. Louis, Missouri, to Cedar Rapids, Iowa
Persons on these flights who have symptoms consistent with mumps within 21 days of travel should be evaluated
for mumps by a health-care provider. Health-care providers should
remain vigilant for mumps among persons with parotitis
or other salivary gland inflammation. Cases of suspected mumps should be reported immediately to public health officials.
A multistate investigation has been initiated by CDC and the state health departments in affected states to notify
potentially exposed passengers (i.e., those seated in close proximity to the index cases). This investigation is using a new
software application, eManifest, developed by the CDC Division of Global Migration and Quarantine (DGMQ) to securely
import, sort, and assign passenger-locating information to
jurisdictions to facilitate timely identification of exposed persons.
These data are securely transmitted to state and territorial health departments via the
Epidemic Information Exchange (Epi-X)
Forum (available at http://www.cdc.gov/mmwr/epix/epix.html) for notification of potentially exposed passengers.
Incidence of mumps in the United States began to decrease after vaccine introduction in 1967 and recommendations
for routine vaccination of children in 1977. Since the 1990s, a further decrease in the reported incidence of mumps has
occurred, which is thought to be attributable to the implementation of the second dose of measles, mumps, and rubella vaccine
risk for transmission of respiratory infectious diseases during air travel might depend on several factors,
including 1) immunity of passengers; 2) infectiousness of the organism; 3) degree of shedding of the pathogen by infected passengers; 4)
hygienic practices of infectious passengers; 5) proximity of others to infectious passengers; 6) hygienic practices of the other
passengers/crew; 7) flight duration; and 8) cabin environment of the aircraft
(4). Transmission of other respiratory pathogens during
air travel has been reported (5--9). Exposure and transmission of mumps during commercial air travel has not been
Reported by:P Quinlisk, MD, Iowa Dept of Public Health. S Redd, G Dayan, MD, National Center for Immunization and
Respiratory Diseases; N Gallagher, Geographic Medicine and Health Promotion Br, P Lutz, K Marienau, MD, F Averhoff, MD, Quarantine and
Border Health Svcs Br, Div of Global Migration and Quarantine, National Center for Infectious Diseases, CDC.
CDC. Postexposure prophylaxis, isolation, and quarantine to control an import-associated measles outbreak---Iowa, 2004. MMWR 2004;
Moser MR, Bend TR, Margolis HS, et al. An outbreak of influenza aboard a commercial airline. Am J Epidemiol 1979;110:1--6.
Klonz KC, Hynes NA, Gunn RA, et al. An outbreak of influenza A/Taiwan/1/86 infections at a naval base and its association with airplane travel.
Am J Epidemiol 1989;129:341--8.
Marsden AG. Influenza outbreak related to air travel. Med J Austral 2003;179:172--3.
Use of trade names and commercial sources is for identification only and does not imply endorsement by the U.S. Department of
Health and Human Services.References to non-CDC sites on the Internet are
provided as a service to MMWR readers and do not constitute or imply
endorsement of these organizations or their programs by CDC or the U.S.
Department of Health and Human Services. CDC is not responsible for the content
of pages found at these sites. URL addresses listed in MMWR were current as of
the date of publication.
All MMWR HTML versions of articles are electronic conversions from ASCII text
into HTML. This conversion may have resulted in character translation or format errors in the HTML version.
Users should not rely on this HTML document, but are referred to the electronic PDF version and/or
the original MMWR paper copy for the official text, figures, and tables.
An original paper copy of this issue can be obtained from the Superintendent of Documents,
U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800.
Contact GPO for current prices.
**Questions or messages regarding errors in formatting should be addressed to