Measles (Rubeola) prevention and control |
Laboratory confirmation |
Whenever someone is suspected to have measles, it is imperative that laboratory confirmation of the illness be achieved. Since laboratory results may not be available for several days to several weeks, but prophylaxis of susceptible contacts has to occur within 6 days of exposure, outbreak control activity has to proceed while laboratory tests are processed.
To confirm measles, serologic testing or viral culture methods are available. Whenever laboratory specimens to confirm measles are collected, please call the health department at the number provided below. We can expedite testing through our laboratory or the state health department laboratory. Often same or next day results are available, and there is no charge to the patient.
Serology |
Draw at least 1ml (2 ml is best) of sera or 4-5 ml blood (8-10 ml is best) in a red or tiger top tube (tubes without anticoagulants or preservatives). Please notify your laboratory that you would like the serologic specimens to go to the local or state health department for testing, otherwise you may be surprised to find that the test result was delayed or inaccurate because the specimen was sent to a distant private laboratory. The state laboratory routinely performs rubella Igm and IgG testing on all specimens submitted for measles testing.
Measles IgM
This is an antibody test that measures the presence of a specific antibody class(IgM) that is only present during acute illness. For the best results, draw samples for measles IgM testing 3 or more days after rash onset. Serologic specimens can be drawn sooner than this as 70-85% of true measles cases will demonstrate IgM antibody by the day of rash onset, however if the test result is negative, the patient should know that another specimen may be required. By the third day after rash onset, 99% of true measles cases will demonstrate IgM antibody.
The Washington state laboratory uses the measles IgM capture technique, which is the most specific and sensitive test available. Unfortunately private laboratories use commercially available test kits that often yield false positive results, because there is frequent cross reaction with other viral agents.
Measles IgG
Both acute and convalescent sera are necessary to determine whether there has been a four fold or greater rise in total measles antibody. To perform the test, draw the first sample during the acute illness and the second (convalescent specimen) 2 to 3 weeks later. The laboratory should determine the antibody results of both specimens in the same laboratory run.
Viral cultures |
These tests look for measles virus. Cultures results are available within 1 to 3 weeks.
Nasal wash
Use 3 to 5 mls of sterile non-bacteriostatic saline and a bulb aspirator or syringe to rinse the nasal passage. Place all of the recovered wash solution in a tube of viral transport medium. Nasal wash must be collected as soon as possible, and within one week after rash onset.
Urine
This is the preferred viral culture technique. Collect 50 to 100 ml of clean voided urine in a sterile container. Urine must be collected as soon as possible and no later than one week after rash onset.
Blood
Collect 5 to 10 ml of blood in a heparinized tube. Please note: Heparinized tubes are used here while measles antibody tests require the use of tubes without anticoagulants.
It is also valuable to conduct laboratory tests appropriate to rule out other potential causes. An example would be a throat culture to look for evidence of streptococcal infection.
Routine measles, mumps and rubella (MMR) immunization recommendations |
All children ages 12 to 15 months and older, and adults born in or after 1957, should be immunized against measles.
Two doses of vaccine are recommended: the first at age 12 to 15 months and the second at entry to kindergarten or 6th grade (depending on year of birth).
Older children and college entrants who have had only one dose of MMR should be given a second dose. (The minimum interval between doses is 1 month.)
Immunizations given before the first birthday or before 1968 should not be counted as valid and should be repeated.
Contraindications |
Children between 12 to 15 months and 5 years of age without documentation of prior MMR who present themselves to medical facilities for any reason should be immunized. In previous measles outbreaks, many of the children with measles had opportunities for immunization at prior office visits.
The only valid contraindications to MMR in children are moderate to severe acute illness, anaphylactic allergy to eggs or neomycin, significant immunosuppression, or recent receipt of immune globulin products or blood.
Children with asymptomatic or mildly symptomatic HIV infection can be given MMR, as well as children with leukemia in full remission who have been off chemotherapy for at least 3 months.
Health care staff |
Health care staff with patient contact born in 1957 or later should have either two documented live measles vaccinations, the first given on or after the first birthday and after 1968 (some vaccines given prior to 1968 were ineffective) or evidence of serologic immunity. It is not necessary to check immune status prior to immunization, however, as persons already immune should experience no significant side effects from additional MMR doses.
Staff born prior to 1957 usually do not require an immunization nor serologic testing as they are probably immune due to a disease exposure in childhood.
Prevent spread of measles |
Medical facilities should promptly screen walk-in patients; every effort should be made to isolate persons with suspected measles. Options include having the patient stay in the car, using a separate door or room, and having the patient wear a face mask when going to the lab, etc. To the extent possible, well child exams should not be scheduled at the same time that measles cases are likely to be seen. Note that airborne transmission via aerosolized droplet nuclei has been documented in closed areas (e.g., exam rooms) for up to 2 hours after a person with measles occupied the area.
Recommendations for managing measles exposures in health care facilities |
References |