Figure 2.3. From 1990 through 2002, rates of acute hepatitis A were higher among males than females. The ratio of male to female rates increased from 1.3 in 1990 to 1.9 in 2001; however, from 2006 through 2009, overall rates declined more among males than among females. In 2009, incidence rates among males (0.7 cases per 100,000 population) were similar to those among females (0.6 cases per 100,000 population).  The peak in acute hepatitis A cases observed for both males and females in 1995 was the last of cyclical peaks that occurred in the United States before availability and use of hepatitis A vaccine.