Tuesday, June 10, 2008

A Parent's Guide to Measles

With the recent measles infections found in DuPage County, parents should be made aware of the following information.

by Dr. Laura Uselding

What is measles?
Measles, also known as Rubeola, is a highly contagious virus that is spread by respiratory droplets that can remain infectious in the air for up to 2 hours. Infection occurs in roughly 90% of people who are exposed and not fully vaccinated. About 1-2 weeks after exposure, those infected begin to experience viral symptoms characterized by mild fever, persistent cough, runny nose, sore throat, and conjunctivitis (pink eye).

Three to four days after the appearance of the initial symptoms, the patient spikes a high fever (103 – 104° F) and a starts exhibiting signs of a papular rash; this rash is red and blotchy with minimal itch. It starts on the head and neck and spreads down the body (see Figure 1). Additionally, patients with measles at this stage also have sores found on the inside of their mouth (see Figure 2). These sores are gray/white on a red background and are located in the inside cheek opposite of the molars. After approximately 1 week, the rash fades in reverse order.
In general, patients with measles are contagious 4 days prior to the presentation of the rash through 4 days after the rash appears.

Why should I be concerned about measles?
Common complications of measles include ear infections (1/10), croup (1/10), and pneumonia, (1/15). One of the most serious complications is encephalitis (1/1000), which is acute swelling of the brain and often results in permanent brain damage. Death can occur in as many as 1-3 individuals per every 1000 infected, usually from respiratory or neurologic complications. Patients less than five years of age and those with weakened immune systems (cancer patients, transplant patients, those on chronic oral steroids, and those with HIV) are at an even higher risk for the more severe complications associated with measles. A much more significant complication is sub acute scalloping panencephalitis, which is a rare degenerative brain disorder resulting in permanent behavioral and intellectual deterioration and seizures. This often occurs 5-10 years after the initial infection. In addition, pregnant women should avoid exposure to measles due to an associated risk of miscarriage, premature labor, and low-birth-weight infants.

Isn’t measles a disease of the past?
Despite the statements declaring that measles was eradicated from the Americas in the year 2000, the CDC states that until it is eradicated world wide, inhabitants in the Americas are still at risk of contracting this virus. In fact, the World Health Organization reports that worldwide, approximately 20 million cases of measles occur each year, and throughout 2008, measles outbreaks have once again been reported throughout the US. Recently, the CDC confirmed 103 cases of measles since January 2008 occurring in California, Virginia, Hawaii, Arizona, Milwaukee, and Chicago. This is the highest number of cases reported since 1996, and it hits extremely close to home. As of June 2, 2008, the DuPage County Health Department has documented the occurrence of measles in seven school age children throughout the county.

Why are we suddenly seeing an increased incidence of measles?
It is believed that the recent surge in cases of measles is due to international travelers and the presence of under or unvaccinated persons living in the U.S. International travelers not only run the risk of bringing measles back from underdeveloped countries who are unable to provide the MMR vaccine to its children, but also run the risk of bringing the virus back from Europe and other developed nations around the world. Many European countries have also experienced a recent surge in measles cases over the past several years. In Switzerland, approximately 2,250 measles cases have been reported since November 2006 and in Israel, there have been approximately 1,000 cases reported in 2008 alone. In general, cases of measles begin in cities with low vaccination rates and quickly spread across the various countries mainly affecting inadequately vaccinated children under 15 years of age who are predominantly members of populations who oppose vaccination.

Why haven’t we seen the same large number of measles cases in the U.S. as we have in the developed nations abroad?
The limited size of recent measles cases in the United States is a result of the highly effective measles and MMR vaccines and the high level of pre-existing vaccination levels in preschool and school-aged children in the U.S. Unfortunately, these numbers could soon change with the growing concern surrounding the occurrence of autism and vaccination. Even though these concerns are unfounded and largely disproven in the medical community, many families who are able to receive the vaccine are opting not to vaccinate their children. Not only does this decision put the children in those families at risk, but it also puts infants too young to be vaccinated and others with a weakened immune system (cancer patients, transplant patients, those on chronic oral steroids, and those with HIV) at risk. Many of the measles cases in the U.S. have occurred in children whose parents claimed exemption from vaccination because of religious or personal beliefs and in infants too young to receive the vaccine. Of the 103 confirmed cased of measles in the U.S., only one person had prior documentation for measles vaccination.

What can be done to prevent my child from contracting measles?
Measles is highly contagious and can remain viable in the air for over two hours. The recent measles outbreaks serve as an important reminder that global travel provides the virus with easy points of entry into the United States, which heightens the need for increased vigilance with vaccination. Complete vaccination confers approximately 98% immunity. The CDC recommends that all children receive two doses of the MMR vaccine (at 12-15 months of age and again at 4-6 years of age), while adults without documented immunity receive at least one MMR dose. If any member of your family is exposed to a measles outbreak, your primary care physician and members of your local health department will determine the best course of action.

What should I do if my family is traveling overseas?
To help prevent acquiring measles during travel, all travelers >1 year of age should receive two doses of measles or the MMR vaccination (at least 1 month apart). For younger travelers between 6 months and 11 months of age, one dose of measles or the MMR vaccination is recommended prior to travel. Anyone vaccinated prior to their first birthday will need two more doses of the vaccine, one between 12-15 months of age and the other between 4-6 years of age.

What should I do if I think my child has been exposed to a person with measles?
Measles is highly contagious, please limit your child’s exposure to others and please notify your primary care doctor immediately. Additionally, tell your primary care doctor’s office or emergency room that you suspect your child or family member has been exposed to measles at the time of check in, so the proper control measures are taken to avoid the spread of the virus. Your physician will take a proper history and if it is consistent with measles, laboratory testing (blood and a nasal swab) will be performed to confirm a diagnosis. Remember that measles is a virus and there is no specific proven antiviral therapy available; therefore, treatment is mainly supportive and the best way to protect someone from the virus is through vaccination. If the exposed person is not properly vaccinated, it may be necessary to keep the patient out of school, daycare, or work for up to 2 weeks. If a documented exposure has occurred, prompt administration of a measles vaccine (within 72 hours) is recommended for unvaccinated people who are >6 months of age since it may decrease the rate of infection and lessen the severity of the disease. It may be necessary to hospitalize and provide intravenous therapy for infants.

Where can I find more information on measles?
CDC Health Advisory on Measles, April 2, 2008 http://www2a.cdc.gov/HAN/ArchiveSys/ViewMsgV.asp?AlertNum=00273

IDPH Memo to Healthcare Providers on Measles in Illinois

CDC website

DCHD website, under Health Alerts and Press Releases

Healthcare Personnel Vaccination Recommendations http://www.immunize.org/catg.d/p2017.pdf

Childhood Vaccine Education Center