By Chris Healey
Unvaccinated individuals are promoting the spread of measles in the United States.
In a public statement on February 21, health officials said seven of fifteen confirmed measles cases in a 2014 California outbreak were reported in individuals who never received a measles vaccine. Health officials have not determined the vaccination status of 6 cases in the outbreak but it is known that in two cases the patients received the vaccine. Over 39,000 cases of measles were reported in California before the measles vaccine was licensed in 1963. In 2005, a record low of four cases were reported.
This outbreak in California is part of a measles resurgence facilitated by rising numbers of unvaccinated individuals. Similar measles trends have been reported across the U.S. According to the CDC, the average number of U.S. measles cases from 2001 to 2010 was 69. In 2013, there were 189 cases.
Measles vaccines are delivered in one of two products produced by Merck– M-M-R II and ProQuad. Both are live-attenuated vaccines, which uses viruses incapable of replication as the pharmacologically-active ingredient. Health experts consider live-attenuated vaccines the most effective of all vaccine types. The measles vaccine schedule recommended by the CDC is 99% effective in conferring immunity.
Vaccination of children after measles vaccine licensure was credited with the elimination of measles in the U.S. in 2000. Measles occurs in the U.S. when individuals are exposed abroad and return to the country. Health officials said three cases in the California outbreak recently traveled to the Philippines. Two traveled to India. Other cases had contact with individuals who traveled abroad.
A growing number of individuals are choosing not to vaccinate their children. Vaccination avoidance has been fueled by unsubstantiated claims of vaccines causing autism in children. The CDC maintains there is no evidence to support a relationship between vaccination and autism. In fact, a recent study published in The Journal of Pediatrics showed no causal link between vaccination and autism.
The CDC’s website states symptoms of measles include fever, cough, inflammation of the mucous membrane, conjunctivitis and a characteristic maculopapular rash. Symptomatic individuals have a chance of developing acute encephalitis and subacute sclerosing panencephalitis, or SSPE, a degenerative disease of the central nervous system. SSPE causes seizures, behavioral problems and intellectual deterioration.
Measles has a fatality rate ranging from one to three deaths for every 1000 cases in the U.S.
Unvaccinated individuals should consult their doctor about receiving a measles vaccine.
Photo Credit: CDC/ Amanda Mills