Live attenuated measles and mumps viral strain-containing vaccines and hearing loss: Vaccine Adverse Reporting System (VAERS), United States, 1990-2003. Asatryan A, Pool V, Chen RT, et al. 2008. Vaccine 26(8): 1166-72.
Explanatory note: Permanent hearing loss in one or both ears is a well known complication of measles, mumps and meningitis. It is also well known to occur in children with congenital rubella syndrome (but not after rubella infection after birth). Routine immunizations have made these diseases—and hearing loss from them—much less common. Measles- and mumps-containing vaccines are live attenuated virus vaccines. Hearing loss after measles or mumps vaccine is, therefore, theoretically plausible.
What are the published and reported cases of hearing loss following immunization with measles- and/or mumps-containing vaccines?
The researchers searched the Vaccine Adverse Effects Reporting System (VAERS) for reports from 1990 to 2003 of possible hearing loss and measles- and/or mumps-containing vaccines, eliminating reports of hearing loss with alternative explanations.
Using estimates of the number of doses of these vaccines given in that same time period in the United States, the researchers calculated the number of cases of hearing loss reported to VAERS per doses of vaccines given.
The researchers also searched the scientific literature for other reported cases of hearing loss after immunization with these vaccines.
The study found 44 cases of hearing loss following measles- and/or mumps-containing vaccine in the VAERS database. This number included cases from other countries and some from before 1990. Hearing loss was bilateral (in both ears) in 21 cases, unilateral (in one ear) in 18 cases, and unknown in 5 cases. The age range was from 11 months to 52 years. The onset of hearing loss ranged from 2 to 89 days following vaccination, peaking on day 10. Of the 32 cases where the information was available, 20 cases were reported after the first dose and 12 after the second dose of vaccine.
Between 1990 and 2003, there were 28 cases in the United States; dividing that number by the doses of vaccine estimated to have been used—168-224 million doses—results in a possible rate of one case per 6-8 million doses.
From the published reports they found an additional 15 cases from 1972 to 1998.
Hearing loss could be a rare complication of measles and/or mumps immunization.
The VAERS database is a passive reporting system that is valuable for looking for signals about possible vaccine complications, as was done in this report. It cannot be used to establish that the vaccine caused a complication because of how the information is collected. Therefore, controlled epidemiologic studies, using a large comprehensive database like the Vaccine Safety Datalink, will be necessary to establish whether hearing loss is caused by measles- or mumps-containing vaccines and, if so, at what rate after vaccination.