Year Cases per 100,000 2000 5.3 2001 1.3 2002 5.1 2003 1.3 2005 7.4 2006 4.8 2007 2.4 2008 1.2 2009 3.5 2010 8 2011 6.7 2012 3.3 2013 11 2014 3.2 2016 3.2 2017 1 2018 5.2 2019 0 2020 2