The figure above is a bar chart showing selected notifiable disease reports for the United States with comparison of provisional 4-week totals through May 12, 2018, with historical data. Reports of acute hepatitis A and acute hepatitis C increased with acute hepatitis A increasing beyond historical limits. Reports of giardiasis, acute hepatitis B, legionellosis, measles, meningococcal disease, mumps and pertussis decreased with acute hepatitis B decreasing beyond historical limits.