The figure above is a bar chart showing selected notifiable disease reports for the United States with comparison of provisional 4-week totals through February 3, 2018, with historical data. Reports of acute hepatitis A, acute hepatitis C, measles and meningococcal disease increased with acute hepatitis A increasing beyond historical limits. Reports of giardiasis, acute hepatitis B, legionellosis, mumps and pertussis decreased with giardiasis and pertussis decreasing beyond historical limits.