Year Cases per 100,000 2000 0 2002 0.96 2003 1.9 2004 1.9 2006 0.95 2007 2.9 2008 4.7 2009 4.7 2010 3.8 2011 1.9 2012 0.93 2014 0 2015 4.6 2016 5.4 2017 2.7 2018 1.8 2019 2.7 2020 0.89