Symptoms


- What are the signs and symptoms of mumps?

The incubation period of mumps is 14-18 days (range, 14-25 days).

The prodromal symptoms are nonspecific, and include myalgia, anorexia, malaise, headache, and low-grade fever. Parotitis is the most common manifestation, and occurs in 30%-40% of infected persons. Parotitis may be unilateral or bilateral and any combination of single or multiple salivary glands may be affected. Parotitis tends to occur within the first 2 days and may first be noted as earache and tenderness on palpation of the angle of the jaw. Symptoms tend to decrease after 1 week and are usually gone by 10 days.

Up to 20% of mumps infections are asymptomatic. An additional 40%-50% may have only nonspecific or primarily respiratory symptoms.

Complications
  • Central nervous system (CNS) involvement in the form of aseptic meningitis is common, occurring asymptomatically (inflammatory cells in cerebrospinal fluid) in 50%-60% of patients. Symptomatic meningitis (headache, stiff neck) occurs in up to 15% of patients and resolves without sequelae in 3-10 days. Adults are at higher risk for this complication than children, and boys are more commonly affected than girls (3:1 ratio). Parotitis may be absent in up to 50% of such patients. Encephalitis is rare (less than 2 per 100,000).
  • Orchitis (testicular inflammation) is the most common complication in postpubertal males. It occurs in up to 20%-50% of postpubertal males, usually after parotitis, but may precede it, begin simultaneously, or occur alone. It is bilateral in up to 30% of affected males. There is usually abrupt onset of testicular swelling, tenderness, nausea, vomiting, and fever. Pain and swelling may subside in 1 week, but tenderness may last for weeks. Approximately 50% of patients with orchitis have some degree of testicular atrophy, but sterility is rare. Oophoritis (ovarian inflammation) occurs in 5% of postpubertal females. It may mimic appendicitis. There is no relationship to impaired fertility.
  • Pancreatitis is infrequent, but occasionally occurs without parotitis; the hyperglycemia is transient and is reversible. While some single instances of diabetes mellitus have been reported, a causal relationship has yet to be conclusively demonstrated; many cases of temporal association have been described both in siblings and individuals, and outbreaks of diabetes have been reported a few months or years after outbreaks of mumps.
  • Deafness caused by mumps is one of the leading causes of acquired sensorineural deafness in childhood. The estimated incidence is approximately 1 per 20,000 reported cases of mumps. Hearing loss is unilateral in approximately 80% of cases and may be associated with vestibular reactions. Onset is usually sudden and results in permanent hearing impairment.
  • Electrocardiogram (EKG) changes compatible with myocarditis are seen in 3%-15% of patients with mumps, but symptomatic involvement is rare. Complete recovery is the rule, but deaths have been reported.
  • Other less common complications of mumps include arthralgia, arthritis, and nephritis. Death from mumps has been reported in 1-3 cases per 10,000 in recent years.

Source : CDC's document on Mumps