Complexity of the Basic Reproduction Number (R).

The basic reproduction number (R), also called the basic reproduction ratio or rate or the basic reproductive rate, is an epidemiologic metric used to describe the contagiousness or transmissibility of infectious agents. R is affected by numerous biological, sociobehavioral, and environmental factors that govern pathogen transmission and, therefore, is usually estimated with various types of complex mathematical models, which make R easily misrepresented, misinterpreted, and misapplied. R is not a biological constant for a pathogen, a rate over time, or a measure of disease severity, and R cannot be modified through vaccination campaigns.

Vaccination Coverage for Selected Vaccines, Exemption Rates, and Provisional Enrollment Among Children in Kindergarten - United States, 2016-17 School Year.

State and local school vaccination requirements help protect students and communities against vaccine-preventable diseases (1). CDC reports vaccination coverage and exemption data for children attending kindergarten (kindergartners) collected by federally funded immunization programs in the United States.* The typical age range for kindergartners is 4-6 years.

Variation in Vaccination Data Available at School Entry Across the United States.

Objectives: To compile substate-level data on US school-age children's vaccination rates.

Methods: For states that did not have suitable data online, in 2015 we submitted information requests to the state health department and followed up with the state's Freedom of Information Act when necessary.

Results: The accessibility, scale, and types of vaccination data varied considerably.

Prevalence of Sports Injuries Among 13- to 15-Year-Old Students in 25 Low- and Middle-Income Countries.

The goal of this study was to compare the sex-specific prevalence rate of serious sports injuries in the past year among students ages 13-15 years from 25 low- and middle-income countries (LMICs) globally. Data from 46,922 nationally-representative students who participated in the Global School-based Student Health Survey (GSHS) were analyzed using complex samples analysis. The GSHS defines injuries as serious when they cause at least one full day of missed school or usual activities or require clinical treatment.

Injury incidence among middle school students aged 13-15 years in 47 low-income and middle-income countries.

A total of 95 811 students aged 13-15 years participated in nationally representative Global School-based Student Health Surveys (GSHS) in 47 low-income and middle-income countries conducted between 2003 and 2012. On average, about 40% of the participants in each country reported at least one injury in the past year that was serious enough to cause the student to miss at least one full day of usual activities (such as school, sports and a job) or to require treatment by a healthcare professional. In 40 of the 47 countries, boys reported a significantly higher injury rate than girls.