Year Cases per 100,000 1980 0 1981 0 1982 57 1983 0 1984 0 1985 14 1986 0 1987 0 1988 0 1989 0 1990 0 1991 0 1992 0 1995 19 1997 0 2001 0 2002 0 2003 0 2004 0 2006 0 2007 0