Mullen J R, Schonberger L B, Manear F L, Bobbitt W R
Public Health Rep. 1977 May-Jun;92(3):217-9.
Between April 18 and May 20, 1975, 16 cases of measles occurred in pupils in an elementary school in Baltimore County, Md., and 1 case occurred in a sibling at a junior high school. Measles was serologically confirmed in 16 of these pupils. Attack rates were determined by grade and by vaccine status. The measles attack rate was 2.1 percent for the 377 children who had been given measles vaccine at 1 year of age or later. The rates were 27.8 percent (13 times higher) for those vaccinated at less than 10 months of age and 20.0 percent (10 times higher) for those with no definite history of vaccine. The higher attack rates for children who were vaccinated only before 10 months of age supports the 1972 recommendation of the Public Health Service Advisory Committee on Immunization Practices that children vaccinated before this age need to be revaccinated with live measles virus vaccine to assure full protection. The finding that 2 of 10 children with a history of measles became ill during the outbreak suggests that such histories are not a totally reliable indicator of immunity. Containment of the outbreak was attributed to the high level of immunity in the community and prompt initiation of control measures.
1975年4月18日至5月20日期间，马里兰州巴尔的摩县一所小学的学生中发生了16例麻疹病例，一名初中学生的兄弟姐妹中出现了1例。其中16名学生的麻疹通过血清学得到确诊。根据年级和疫苗接种情况确定了发病率。对于1岁及以后接种过麻疹疫苗的377名儿童，麻疹发病率为2.1%。10个月龄以下接种疫苗的儿童发病率为27.8%（高出13倍），无明确疫苗接种史的儿童发病率为20.0%（高出10倍）。仅在10个月龄前接种疫苗的儿童发病率较高，这支持了公共卫生服务免疫实践咨询委员会1972年的建议，即在此年龄前接种疫苗的儿童需要用麻疹活病毒疫苗重新接种以确保充分的保护。在此次疫情爆发期间，有麻疹病史的10名儿童中有2名患病，这一发现表明此类病史并非完全可靠的免疫指标。此次疫情的控制归因于社区的高免疫水平和及时采取的控制措施。
