Physical signs
Effects on pregnancy and the unborn baby
Tests and treatments
Mumps is caused by a myxovirus that infects the parotid glands in the neck (which produce saliva). The virus is spread by the infected person coughing and sneezing or coming in contact with contaminated items (such as their tissues, drinking glasses or soiled hands). Mumps is infectious for 1 to 2 days before symptoms start, until about 9 days after the swelling appears. It usually infects children between the ages of 5 and 15 years, but can occasionally infect non-immune adults. Being infected once generally provides lifelong immunity. Most adults are immune, even if they can't remember having the illness, as sometimes there are no physical signs or they are very mild.
The incubation period for mumps (or the time period from coming in contact with the virus and becoming ill) is about 12 to 28 days, with an average of 18 days.
Physical signs
Up to 15 to 20% of people do not show any physical signs when infected with mumps. Those who do become ill can experience fever, headache, loss of appetite, swollen, tender glands, pain and soreness around the jaw and neck and possibly abdominal pain and/or back pain.
Up to 30% of adult men infected with mumps develop swollen, painful testicles (called 'orchitis'). This can appear up to 7 to 10 days after the swelling starts in the neck. Contrary to popular belief, this rarely leads to fertility problems. Women may experience inflamed ovaries (or 'oophoritis'). This also does not appear to affect fertility. In very rare cases, mumps can cause an infection of the brain (meningoencephalitis), although most people recover well without treatments. Another very rare complication is hearing loss.
Effects on pregnancy and the unborn baby
A natural mumps infection during pregnancy does not cause birth defects or premature birth.