There are several problems that often occur with mumps. These can be worrying, but they're rarely serious and usually improve as the infection passes.
Pain and swelling of the testicle (orchitis) affects one in four males who get mumps after puberty. The swelling is usually sudden and affects only one testicle. The testicle may also feel warm and tender.
In affected boys and men, swelling of the testicle normally begins four to eight days after the swelling of the parotid gland. Occasionally, swelling can occur up to six weeks after the swelling of the glands.
Any testicle pain can be eased using over-the-counter painkillers such as paracetamol or ibuprofen. If the pain is particularly severe, contact your GP, who may prescribe a stronger painkiller for you.
Applying cold or warm compresses to your testicle and wearing supportive underwear may also reduce any pain.
Just under half of all males who get mumps-related orchitis notice some shrinkage of their testicles and an estimated 1 in 10 men experience a drop in their sperm count (the amount of healthy sperm their body can produce). However, this is very rarely large enough to cause infertility.
One in 20 females who get mumps after puberty experience swelling of the ovaries (oophoritis), which can cause:
The symptoms of oophoritis usually pass once the body has fought off the underlying mumps infection.
Viral meningitis can occur if the mumps virus spreads into the outer protective layer of the brain (the meninges). It occurs in about one in seven cases of mumps.
Unlike bacterial meningitis, which is regarded as a potentially life-threatening medical emergency, viral meningitis causes milder, flu-like symptoms, and the risk of serious complications is low.
Sensitivity to light, neck stiffness and headaches are common symptoms of viral meningitis. These usually pass within 14 days.
About 1 in 20 cases of mumps lead to short-term inflammation of the pancreas (acute pancreatitis). The most common symptom is sudden pain in the centre of your belly. Other symptoms of acute pancreatitis can include:
Although pancreatitis associated with mumps is usually mild, you may be admitted to hospital so your body functions can be supported until your pancreas recovers.
Rare but potentially serious complications of mumps include an infection of the brain itself, known as encephalitis. This is thought to occur in around 1 in 1,000 people who develop viral meningitis from mumps. Encephalitis is a potentially fatal condition that requires admission to a hospital intensive care unit. About 1 in 20 people with mumps experience some temporary hearing loss, but permanent loss of hearing is rare. It's estimated this occurs in around 1 in 20,000 cases of mumps.