East Coast Mumps Outbreak Imported From Britain
The continuing mumps outbreak in New York and New Jersey—which has affected more than 1500 individuals, most of them Orthodox Jewish boys—is traced to an 11-year-old who visited Britain in June of last year, reports the CDC.
More than 7400 laboratory-confirmed cases of mumps were recorded in the United Kingdom in 2009. The case number is lower than those seen during the epidemic of 2004 and 2005, the UK Health Protection Agency reports, but greater than cases reported during 2007 and 2008.*
The US mumps outbreak continues despite the relatively high rate of vaccination among the infected—88% had received at least 1 vaccine dose; 75%, 2 doses. However, the mumps component of the MMR vaccine provides less protection than the measles or rubella components. The CDC provides an estimated mumps-vaccine efficacy of 73%-91% after 1 dose and 79%-95% after 2 doses.
Among the most common symptoms of mumps among boys is orchitis, or testicular inflammation. According to one source, about 20% of prepubertal boys will develop this painful condition. Consequent risks include testicular atrophy and sterility.
* A resurgence of mumps and measles cases in the United Kingdom is blamed on reduced vaccination rates–which are believed to be (at least partly) the result of the 1998 study of Andrew Wakefield et al linking the MMR vaccine with autism. The discredited study was recently retracted by The Lancet.
Photo of child with parotid gland swelling due to mumps from the CDC/NIP/Barbara Rice.