Disease Pathway: How does Measles Affect your Body?
Why has the medical community, general public, and media paid such close attention to measles over the last half century? That’s because measles is one of the top causes of death in children. Measles is the most transmittable infectious disease on the planet (1). This highly contagious disease is caused by a viral infection. The virus is paramyxovirus belonging to the genus Morbillivirus. The virus has two vital proteins. F (fusion) protein coordinates fusion of the virus and the host cell, in addition to viral penetration and hemolysis. The H (hemagglutinin) protein controls the virus’ absorption into the cells. Measles virus is dangerous because it is a systemic infection that first invades the respiratory epithelium of the nasopharynx. Once the virus has infected and replicated in the epithelium after two to three days, the virus infects the reticuloendothelial system and enters the blood. After five to seven days, a second infection of the blood occurs spreading to other organs and tissues (1). For more information of measles pathology and laboratory diagnosis click here.
Eight to ten days after exposure, symptoms will begin to appear. Symptoms include:
- Runny Nose
Severe complications include pneumonia, encephalitis, and death (1). The promising news is measles does have an effective preventative intervention. A review of 69 published studies from 1969 to 2006 assessing measles vaccine showed that the vaccine is 90% effective overall and 92% effective when administered over 12 months of age (2).
Explanation of Measles: Disease, Transmission, and Vaccine
Measles in the Air: Transmission to Contagion
What characteristics make measles such a deadly carrier? Measles is passed in an unbroken chain from human to human without any known animal or vector reservoir. Researchers have yet to discover an asymptomatic carrier state for the disease. Measles is transmitted primarily through respiratory droplets. According to studies conducted at Massachusetts Institute of Technology, measles has a greater than 90% secondary attack rates of infection of susceptible person once in contact with the virus (2). Airborne transmission, such as coughing in a closed area, through aerosolized droplet nuclei has been evidenced for up to two hours after the person with measles entered the area. The virus can be transmitted between humans from four days before up until four days after the first appearance of a rash. The maximum transmission occurrs from the onset of the prodrome till three to four days after the rash onset (1).
My Child was Not Vaccinated: Can Measles be Treated?
According to physicians and researchers at the Mayo Clinic, measles cannot be treated. However if a non-immunized person comes in contact with the measles virus, injection with the vaccination can be effective within 72 hours after exposure. This can fully or partially decrease the symptoms and duration of infection. For individuals that are ineligible to receive the vaccination due to medical exemptions, a physician can give an injection of weakened antibodies, immune serum globulin, within six days after initial exposure (3).
If exposed to the virus, medications can be given to reduce severity of side effects:
- Acetaminophen, Ibuprofen, or Naproxen –> Reduce fever.
- Antibiotics –> Treat bacterial infections such as pneumonia or an ear infection.
- Vitamin A –> Lessen the severity of measles.
I get how measles works. Where does the story begin?
BELOW: Now that you know more about measles, explore the frequency of usage among words relevant to this controversy through Google’s Ngram viewer. As you navigate through the measles story, you can come back to this diagram to see what potential correlations can be drawn. For example, notice that the use of “measles” began to decrease with the advent of the immunization and was especially low during the 2000 elimination. Do you think there is a correlation between the increase in usage with the increase of skepticism in the 1980s? Predict how you think the use of “measles” changed due to outbreaks post 2000.
1. Measles Epidemiology and Prevention of Vaccine-Preventable Diseases. Centers for Disease Control and Prevention, 07 May 2012. Web. 17 Apr. 2015. <http://www.cdc.gov/vaccines/pubs/pinkbook/meas.html>.
2. Moss WJ. Measles control and the prospect of eradication. Curr Top Microbiol Immunol.2009;330:173–189.
3. Mayo Clinic Staff. “Measles.” Treatments and Drugs. Mayo Clinic, 2015. Web. 28 May 2015. <http://www.mayoclinic.org/diseases-conditions/measles/basics/treatment/con-20019675>.