The measles vaccine was introduced in the US 50 years ago, and now a panel from the Centers for Disease Control and Prevention has said the elimination of measles, rubella and congenital rubella syndrome has endured through 2011. However, the organization warns that measles still poses a threat, citing a 2013 spike in cases.
The conclusions from the Centers for Disease Control and Prevention (CDC) report were published in JAMA Pediatrics.
Investigators note that before the US vaccination program began in 1963, almost every child became infected with measles – a highly infectious viral illness that can lead to serious complications, including death.
Each year, between 450 and 500 individuals died, while 48,000 were hospitalized, 7,000 had seizures and around 1,000 experienced permanent brain damage or deafness.
Researchers from the CDC, led by Dr. Mark J. Papania, summarized the data from the US national report on measles, rubella and congenital rubella syndrome (CRS) elimination. They say their study follows on from verification of the elimination of measles in 2000 and of rubella in 2004.
It is important to note that “elimination” does not mean that there are zero cases of the illnesses, as some cases occur when people are infected abroad and bring it back to the US, where it can then be transmitted locally.
Therefore, the team says they define elimination as the “absence of a chain of transmission that is continuous for 12 months or more.”
According to the study, the US is the most populous country to have eliminated measles, rubella and CRS, which can cause birth defects in children of mothers infected with rubella.
The reported incidence of measles in the US has stayed below one case per 1 million population since 2001. Meanwhile, rubella incidence has remained below one case per 10 million population since 2004, with CRS incidence staying below one case per 5 million births.
Additionally, the study shows that 88% of measles cases and 54% of rubella cases came from abroad.
The CDC says people who are infected abroad continue to spark outbreaks among groups of unvaccinated people. Although there are usually around 60 cases per year in the US, 2013 has so far seen 175 cases of the illness.
The study authors say vaccination is vital:
“The keys to ongoing success will be sustaining high levels of immunity throughout the US population through vaccination, maintaining strong US surveillance and public health response capacity and supporting other countries in efforts to control and eliminate measles, rubella and CRS.”
However, the debate over vaccinations continues in the public arena, where parents and public figures continue to question the safety of vaccinating children.
In a linked editorial to the latest study, Dr. Mark Grabowsky, of the Office of the Secretary General’s Special Envoy for Financing the Health Millennium Development Goals and for Malaria, New York, writes about the benefits the US has seen as a result of vaccination.
“The elimination of measles and rubella from the Western Hemisphere is a triumph of public health with several important implications,” he says.
“First, imported cases of measles and rubella will still likely occur as long as there remain endemic areas in the world.” He says that a “second implication of the elimination of measles and rubella in the Western Hemisphere is that it is a vindication of US vaccination strategy.”
However, Dr. Grabowsky warns against skipping this vaccination:
“The greatest threat to the US vaccination program may now come from parents’ hesitancy to vaccinate their children. Although this so-called vaccine hesitancy has not become as widespread in the United States as it appears to have become in Europe, it is increasing.”
CDC Director Dr. Tom Frieden also warns of the risks of the illness, noting that “a measles outbreak anywhere is a risk everywhere.”
“The steady arrival of measles in the US is a constant reminder that deadly diseases are testing our health security every day,” he adds.
The CDC adds that like smallpox, measles can be eliminated, but because it is so contagious, “the vast majority of a population” would need to be vaccinated in order to prevent further outbreaks.