Measles Cases for 2019 Already Outpace Last Year

Measles  outbreaks are continuing in the U.S, with the number of cases already outpacing  last year's  levels. At the beginning of May, according to the Centers for Disease Control  and Prevention  (CDC), there were already 764 cases of measles since January 1, 2019. Last year,  there were a total of 372 cases. (The number of cases is updated weekly by the  CDC.)

In  fact, the level of 2019 measles cases is the largest number reported in the U.S.  since 1994 and since measles was declared eliminated in 2000. These outbreaks  are linked to unvaccinated travelers who are infected abroad in countries such  as Israel, Ukraine, and the Philippines, where large measles outbreaks are  occurring. When these travelers return to the U.S., they spread the infection  mostly to unvaccinated children and adults in their communities. In the U.S.,  the hardest hit communities include Rockland County in New York State, New York  City, Washington State, New Jersey, Butte County and others in California, and  Michigan.

Measles  is a very contagious viral infection  and is easily spread when infected people cough and/or sneeze, dispersing  droplets in the air that other people breathe. Measles can also spread when  people touch contaminated surfaces (e.g., door knobs, tables) and then touch  their face, nose, mouth or eyes. An infected person can spread measles even  before they have symptoms (e.g., high fever, cough, runny nose, red and watery  eyes, and then a rash that starts on the face and spreads down to the trunk and  legs). According to the CDC, nine out of ten people who aren't vaccinated for  the disease will get the virus if they come in contact with an infected  person.

The  CDC recommends two doses of the vaccine to  protect against measles as well as mumps and rubella(MMR).  Usually children are given the first dose between ages 12 and 15 months and the  second dose between ages 4 and 6 years old. Because many American children get  the measles vaccine, infections are relatively rare in the U.S., but millions of  cases occur around the world.

Many  people don't realize how contagious measles is and that it can become a serious  infection. While most people recover from measles in a week or so, in some  cases, it can lead to complications including pneumonia ,  permanent brain damage, deafness and even death, according to the CDC. About one  to two people out of 1,000 who get measles die. Serious complications primarily  affect babies and children but can also occur in adults who never had measles or  the vaccine, or whose immunity has  waned. There is no treatment for measles other than supportive care (resting and  drinking plenty of liquids).

Confirming  suspected cases of measles with laboratory testing is very important for both  sporadic cases and outbreaks. Testing is used to verify that the infection is  measles as well as to help health departments track outbreaks and take measures  to limit spread of the disease.

The  most common tests for diagnosing acute measles infection include a blood test  that measures antibodies (immunoglobulin M, IgM)  produced in response to the measles virus and tests for detecting the virus  directly either in blood or in a swab from the back of the nose and throat. Only  patients with symptoms consistent with measles should be tested. The CDC advises  healthcare practitioners who suspect a case of measles to notify their state or  local public health officials and to collect both types of samples for  testing.

During  outbreaks, samples from people suspected of having measles are often sent to  public health laboratories  for  IgM antibody testing or detection of the virus by PCR.  If the virus is detected, they can do a genetic test called genotyping, which  can be used to determine the genetic makeup of the virus from a particular case  or outbreak and help link or unlink cases. Information from genotype testing,  performed in public health labs, may help determine where the outbreak might  have started and how it spread. (For more details, read the article  on Infectious Disease Genetic Testing.)

In  one of the most recent outbreaks, health officials were able to identify the  individual initially responsible for spreading measles from New York to Michigan  (Patient Zero). According to a report in the Washington  Post, laboratory  tests verified that this individual had measles, and genetic testing confirmed  that the strain of measles the individual had matched the viral strain causing  the New York City outbreak. Health officials followed-up by contacting the  people Patient Zero had visited and tested them for measles. Cooperation between  the health officials and community leaders seems to have helped control further  spread of measles within the group, according to the report.