Nationally Notifiable Infectious Diseases and Conditions, United States: Weekly Tables
![The figure is a bar chart showing selected notifiable disease reports for the United States with comparison of provisional 4-week totals through March 24, 2018, with historical data. Reports of acute hepatitis A, acute hepatitis C and legionellosis increased with acute hepatitis A increasing beyond historical limits. Reports of giardiasis, acute hepatitis B, measles, meningococcal disease, mumps and pertussis decreased with pertussis decreasing beyond historical limits.](/nndss/static/2018/12/2018-12-figure1.jpg)
- * Ratio of current 4-week total to mean of 15 4-week totals (from previous, comparable, and subsequent 4-week periods for the past 5 years). The point where the hatched area begins is based on the mean and two standard deviations of these 4-week totals.