Missouriwatcher
Editor, Senior Moderator
"...The mumps outbreak in the New York-New Jersey area has grown substantially, and anecdotal reports from certain affected areas suggest that the rate of new cases is not decreasing; the appearance of a downward trend in recent weeks is partly a result of reporting delays. The outbreak is occurring almost exclusively in a specific religious community, and no cases outside this community have resulted in sustained transmission.
Like the mumps outbreaks that occurred in 2006, much of the current outbreak is occurring in congregate settings, where prolonged, close contact among persons might be facilitating transmission. Within the affected religious community, cases have occurred predominantly among school-aged boys, who attend separate schools from girls. The higher rate among boys might be a result of the additional hours that boys in this community spend in school compared with girls, including long periods in large study halls, often face-to-face with a study partner...
In this outbreak, as in other recent mumps outbreaks among highly vaccinated populations, most cases have occurred in vaccinated persons. The mumps vaccine has greatly reduced the incidence of mumps in the United States. From 1967, when the mumps vaccine was first licensed, to the early 2000s, the number of reported cases decreased from 186,000 to <500 annually. Nonetheless, the effectiveness of the mumps component of the MMR vaccine is lower than that of the measles and rubella components. Estimates of the effectiveness of the mumps vaccine have varied in previous studies, ranging from 73% to 91% after 1 dose and from 79% to 95% after 2 doses (3--5). At least one study found 2 doses to be more effective than 1 dose.
Public health officials began offering a third dose of vaccine to students in certain schools in Orange County, New York, because mumps transmission had continued among students, despite their high rate of 2-dose coverage. Although a previous study indicated that a third dose of MMR vaccine for seronegative college students resulted in rapid seroconversion with a low rate of IgM response, which is indicative of an anamnestic immune response, ACIP has not recommended a third dose, and no data exist on the effectiveness of a third dose in either reducing the risk for mumps or altering the course of an outbreak. Data obtained from use of the third dose of MMR vaccine in Orange County might be used to guide future options for mumps outbreak control in settings with high 2-dose coverage.
This outbreak emphasizes that mumps outbreaks can occur in highly vaccinated populations. Although several factors play a role in mumps control in the United States, maintenance of high 2-dose MMR vaccine coverage remains the most effective way to prevent and limit the size of mumps outbreaks."
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5905a1.htm?s_cid=mm5905a1_e
Like the mumps outbreaks that occurred in 2006, much of the current outbreak is occurring in congregate settings, where prolonged, close contact among persons might be facilitating transmission. Within the affected religious community, cases have occurred predominantly among school-aged boys, who attend separate schools from girls. The higher rate among boys might be a result of the additional hours that boys in this community spend in school compared with girls, including long periods in large study halls, often face-to-face with a study partner...
In this outbreak, as in other recent mumps outbreaks among highly vaccinated populations, most cases have occurred in vaccinated persons. The mumps vaccine has greatly reduced the incidence of mumps in the United States. From 1967, when the mumps vaccine was first licensed, to the early 2000s, the number of reported cases decreased from 186,000 to <500 annually. Nonetheless, the effectiveness of the mumps component of the MMR vaccine is lower than that of the measles and rubella components. Estimates of the effectiveness of the mumps vaccine have varied in previous studies, ranging from 73% to 91% after 1 dose and from 79% to 95% after 2 doses (3--5). At least one study found 2 doses to be more effective than 1 dose.
Public health officials began offering a third dose of vaccine to students in certain schools in Orange County, New York, because mumps transmission had continued among students, despite their high rate of 2-dose coverage. Although a previous study indicated that a third dose of MMR vaccine for seronegative college students resulted in rapid seroconversion with a low rate of IgM response, which is indicative of an anamnestic immune response, ACIP has not recommended a third dose, and no data exist on the effectiveness of a third dose in either reducing the risk for mumps or altering the course of an outbreak. Data obtained from use of the third dose of MMR vaccine in Orange County might be used to guide future options for mumps outbreak control in settings with high 2-dose coverage.
This outbreak emphasizes that mumps outbreaks can occur in highly vaccinated populations. Although several factors play a role in mumps control in the United States, maintenance of high 2-dose MMR vaccine coverage remains the most effective way to prevent and limit the size of mumps outbreaks."
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5905a1.htm?s_cid=mm5905a1_e
