Monday, November 7, 2016

Deadly Complication of Measles More Common Than Previously Thought

A complication of measles that can kill children years after they have the infection is more common than researchers previously thought.

Before the advent of MMR vaccinations, nearly every child came down with measles.

The familiar viral infection that causes the distinctive red rash is extremely contagious. Fully 90 percent of people who are exposed to the virus develop the disease. Any contact with mucus or saliva can transmit the virus, and people are capable of spreading the disease 48 hours before they display symptoms. A sneeze can leave billions of copies of the virus that remain viable for up to two hours on clothes, toys, upholstery, food, countertops, and door knobs. If one child in a classroom or at a party has the disease, nearly all or all of the other children present will soon have it, too.

Measles doesn't just cause a rash. The first sign of infection is usually a fever greater than 104o F (40o C), that lasts from one to seven days. Infected people (who can be of any age) then develop the three C's, cough, conjunctivitis (eye inflammation), and coryza (in the terminology of children who get measles, nose boogers). Any of the secretions from the three C's are highly contagious as long as they are wet. There can be sensitivity to light, swelling around the eyes, and flu-like muscle pain. The rash doesn't appear until two to four days after other symptoms, and then lasts for up to a week. The rash only occurs in people who have active immune systems; children and adults who have HIV or who are on immunosuppressant drugs won't develop the rash at all.

Even people who have normal immune systems before they are exposed to measles won't have normal immune systems afterward. The virus itself is an immune suppressing agent. The immune system doesn't respond as quickly as usual to infections for several months after measles. Anyone who has measles is at increased risk for giant cell pneumonia, about 1 in 20 developing pneumonia after catching measles, but especially:
  • Children, whose immune systems haven't had enough experience dealing with infections to have developed antibodies,
  • Children who are deficient in zinc or vitamin A, and
  • Anyone who has a condition or who takes medications that reduce immune response.
Women who catch measles during pregnancy tend to develop "symptoms for two" with severe complications.

Deaths from measles are most common among infants. Every year, several hundred thousand children who have not reached the age of five die of the disease, although giving a single dose of vitamin A (as many national health services and relief organizations now attempt to do) can make the difference between life and death.

The overall rate of death from measles is about 0.1 percent, or at least so researchers thought until they began studying yet another complication of measles called subacute sclerosing panencephalitis, or SSPE. The death rate from this condition of brain inflammation is about 10 percent, and fully 1 percent of people who develop measles may develop some degree of brain inflammation. The scary part of the condition is that it may not appear until years after the measles are gone, at age 10, or age 15, or age 20, or even later in adult life.

What You Need to Know About the Measles Complication SSPE

Subacute sclerosing panencephalitis causes a variety of symptoms not usually associated with measles, including:
  • Unsteady gait, difficulties walking at normal speeds.
  • School problems.
  • Gradual changes in behavior leading to
  • Bizarre behavior.
  • Dementia.
  • Spastic or jerking movements.
  • Weakness in the legs.
  • Symptoms that may be mistaken for schizophrenia.
  • Fatigue.
  • Depression.
  • Coma and death.
These changes in the brain cause a profound loss of quality of life, but they usually aren't fatal outright. However, not being able to cross an intersection before a careless driver runs a red light, or angering a person with his or her own psychiatric problems and a weapon, or making a horrible choice with medication or toxic household cleaning agents or hitting the head during a seizure can and do result in deaths. They aren't obviously the result of the brain condition, but the end result is nonetheless mortality.

Doctors used to think there were only about 10 cases of SSPE per year in the United States, and maybe a similar number of cases in Europe. The condition was noted in several thousand people every year in India. However, researchers at the David Geffen School of Medicine at the University of California in Los Angeles and the California public health agency have found that the rate among babies who catch measles before they can be vaccinated (the shots aren't given before the age of fifteen months because the immune system isn't ready for them, antibodies from the mother interfere with the shot) is about 1 in 609. The average age at diagnosis is 12, but cases have occurred in patients aged 3 to 35.

That doesn't sound like a very high rate. But what that means is that whenever there is an outbreak of measles, at least one child faces a horrible fate. What can be done to avoid this possibility?
  • Get your child vaccinated, twice. About 5 to 10 percent of first vaccinations fail, so the second injection is necessary to ensure immunity to the disease. Where 90 percent or more of children are vaccinated, the other 10 percent are protected by herd immunity; there simply is no one to infect them.
  • If you don't get your child vaccinated, keep them out of crowds when there has been an announcement of measles in your area.
  • Keep your unvaccinated baby away from children who could be infected with the disease. Remember, measles is contagious before symptoms appear. If your local public health department has announced that there are cases of measles in your area, unvaccinated children can catch the infection and transmit it to your child.
  • Wash your hands with soap and water frequently. Don't be the person who transfers germs to your child. Teach your children to wash their hands after coming in contact with mucus or saliva before they touch their hands to the mouths or faces.
  • Make sure your child gets foods that are rich in vitamin A at least occasionally. In the twentieth century, the main source of vitamin A was cod liver oil. It's still a great source of vitamin A, but so are butter, whole milk, and mother's milk. If you are breastfeeding your child, you can be the person to take the cod liver oil to make sure your child gets the vitamin A.
Image credit: By Mike Blyth - Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=2663382

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