If approximately 80 percent of all urban 2-year-olds received the measles vaccine, most measles outbreaks could be prevented, the results of a new study suggest.
The study, based on a survey of 1,011 children in Milwaukee under the age of 17 who had a confirmed case of the measles between September 1989 and June 1990, found that measles outbreaks were unlikely to occur in neighborhoods in which at least 80 percent of the toddlers were immunized.
Over all, about 68.5 percent of the 2-year-olds in the city had received at least one dose of vaccine, the study said.
"Modest improvements in low levels of immunization coverage among 2-year-olds confer substantial protection against measles outbreaks," concluded the researchers from the Wisconsin Health Department and the U.S. Centers for Disease Control.
The study, which was published in the Feb. 12 issue of the Journal of the American Medical Association, found that, in areas where the immunization rate for toddlers was 60 percent, the number of measles cases was half that in areas with immunization rates of 50 percent. At a 70 percent immunization rate, the study found, the incidence of measles was lowered by 86 percent. At an 81 percent immunization rate, the number of measles cases was virtually zero, they found.
Young urban adolescents who have had many sexual partners are less likely to use condoms to protect themselves against the virus that causes AIDS than are less sexually experienced students, a new study has found.
Like previous studies on teenagers and condom use, this report, completed by researchers from the University of California at San Francisco and the California Public Health Foundation, found no relationship between a teenager's knowledge about AIDs and his or her use of condoms.
But the study, which appeared in the February issue of Pediatrics, found that teenagers who had three or more sex partners were half as likely to use condoms consistently as were the other urban, junior-high-school students surveyed.
Only 37 percent of highschool students engage in exercise for at least 20 minutes three or more times a week, a new C.D.C. study has found.
The study, part of the C.D.C.'S national Youth Risk Behavior Survey, found that white male students were the most likely to participate in vigorous exercise, and black females were the least likely to.
The study suggests that adolescents are less active than they were even a decade ago.
In 1984, a federal study found that 61.7 percent of students in grades 10-12 regularly exercised, compared with 36.1 percent of the students in grades 10-12 in the current study.