INITIAL SYMPTOMS
Headache and low-grade fever is followed in about 12-24 hours by parotid gland swelling, higher fever, and painful chewing/swallowing, especially acidic foods such as vinegar and lemon juice. [Merck Manual, p. 2762]
PRECAUTIONS
"The index case-patient should be isolated, and respiratory precautions (gown and gloves) should be used for patient contact. Negative pressure rooms are not required. The patient should be isolated for 5 days after the onset of parotitis, during which time shedding of virus is likely to occur." [ACIP, 2011]
COMMENTS
FINDINGS:
Symptoms include swelling of one or more salivary glands, usually the parotids. [CCDM, p. 419-23] Swelling of parotid gland is greatest on the second day and lasts 5-7 days. The tender swelling is in front and below the ear. The opening of Stensen's duct (opposite the second upper molar tooth) is red, but no pus. [Merck Manual, p. 2762] About 1/2 of infections are asymptomatic except for nonspecific respiratory symptoms. A prodrome of low-grade fever, malaise, myalgia, headache, and anorexia precedes the parotitis by 1-7 days. Patients with parotitis have difficulty eating, swallowing, or talking and may have an earache. [Harrison ID, p. 939] In the pre-vaccine era, mumps affected primarily children under the age of 14. In 2001, 49% of patients were older than 15. The parotid gland enlarges in 60% to 70% of cases and the submandibular or sublingual glands in 10% of cases. 50% of mumps cases have CSF pleocytosis. Mumps meningitis is benign without sequelae. [PPID, p. 2088-9, Table 157.1] Symptoms of meningitis are stiff neck, headache, vomiting, and lethargy. In 40-50% of cases of documented mumps meningitis, patients do not have parotitis. Encephalitis is rare; symptoms include high fever, delirium, seizures, and paresis. [Cecil, p. 2172-3] WBC count is usually normal, but may be elevated in cases with orchitis. Amylase is elevated in first week of parotitis. Serum lipase is normal. [Wallach, p. 1183-4]
COMPLICATIONS:
Complications include orchitis, hearing loss, pancreatitis, and, rarely, encephalitis. Up to 10% of patients have symptomatic aseptic meningitis. [CCDM, p. 419-23] Encephalitis occurs in about 0.1% of cases. Epididymo-orchitis occurs in 25% of infected post-pubertal males. The testicle may enlarge 3-4 times normal size. Sterility is rare. 5-15% of mumps patients have EKG abnormalities, but clinical myocarditis is rare. Thrombocytopenia is extremely rare. Elevated amylase in a patient with aseptic meningitis suggests mumps. [PPID, p. 2089-90] Arthritis is a complication in 0.4% of patients. Postinfectious syndromes include transverse myelitis, facial paralysis, and polyneuritis. [ID, p. 1212-3] About 1-10% of patients have signs of meningeal irritation (stiff neck). Oophoritis is a complication in about 5% of adult women with mumps, and it presents as abdominal pain. [Cohen, p. 1405] Leukocytosis may occur with meningitis, orchitis, or pancreatitis. Serum amylase is elevated for about 2-3 weeks in cases of parotitis. [PPID, p. 2091] Extremely rare complications are prostatitis, nephritis, myocarditis, hepatitis, polyarthritis, deafness, and lacrimal gland involvement. [Merck Manual, p. 2762]
PREVENTION:
"For unvaccinated personnel born before 1957 who lack laboratory evidence of mumps immunity or laboratory confirmation of disease, health-care facilities should consider vaccinating personnel with 2 doses of MMR vaccine at the appropriate interval; for unvaccinated personnel born before 1957 who lack laboratory evidence of mumps immunity or laboratory confirmation of disease, health-care facilities should recommend 2 doses of MMR vaccine during an outbreak of mumps." [ACIP, 2011]
"If mumps exposures occur in a health-care facility, all contacts should be evaluated for evidence of mumps immunity. HCP with no evidence of mumps immunity who are exposed to patients with mumps should be offered the first dose of MMR vaccine as soon as possible, but vaccine can be administered at any interval following exposure; they should be excluded from duty from day 12 after the first unprotected exposure through day 25 after the most recent exposure. HCP with documentation of 1 vaccine dose may remain at work and should receive the second dose. HCP with mumps should be excluded from work for 5 days from the onset of parotitis." [ACIP, 2011]
REFERENCES FOR CASES/YEAR
1. (US) Published in MMWR 2011: 404; "From January 1 to August 15, 2014, 965 people in the United States have been reported to have mumps. Outbreaks in at least four U.S. universities have contributed to these cases:" [http://www.cdc.gov/mumps/outbreaks.html] Guesstimate = 2000;
2. (Global) 100-1000 cases per 100,000 in countries lacking mumps vaccination; [Harrison ID, p. 938] In 2012, 120 of 194 WHO Member States had national mumps immunization programs. [CCDM, p. 421] Guesstimate: Assume 1/2 of population immunized, 550 cases per 100,000 is rate for 3 trillion (30,000 X 100,000); Calculate 550 X 30,000 = 16,500,000;