Between 1990 and 2000, the rate dropped to less than 1 per one million, meaning the disease is extremely rare in the United States today.In Europe, tularemia is generally rare, though outbreaks with hundreds of cases occur every few years in neighboring Finland and Sweden. In Sweden over a period from 1984 to 2012 a total of 4,830 cases of tularemia occurred (most of the infections were acquired within the country). About 1.86 cases per 100,000 persons occur each year with higher rates in those between 55 and 70. Outbreaks
From May to October 2000, an outbreak of tularemia in Marthas Vineyard, Massachusetts, resulted in one fatality, and brought the interest of the United States Centers for Disease Control and Prevention (CDC) as a potential investigative ground for aerosolised Francisella tularensis. For a time, Marthas Vineyard was identified as the only place in the world where documented cases of tularemia resulted from lawn mowing. However, in May 2015 a resident of Lafayette, Colorado, died from aerosolised F. tularensis, which was also connected to lawn mowing, highlighting this new vector of risk. An outbreak of tularemia occurred in Kosovo in 1999–2000.In 2004, three researchers at Boston Medical Center, in Massachusetts, were accidentally infected with F. tularensis, after apparently failing to follow safety procedures.In 2005, small amounts of F. tularensis were detected in the National Mall area of Washington, D.C., the morning after an antiwar demonstration on September 24, 2005. Biohazard sensors were triggered at six locations surrounding the Mall.
2
          
          
            FeSO
            
              4
            
            
              
            
          
          
            
              →
              
                Δ
              
            
          
          
            Fe
            
              2
            
            
              
            
          
          
            O
            
              3
            
            
              
            
          
          +
          
            SO
            
              2
            
            
              
            
          
          +
          
            SO
            
              3
            
            
              
            
          
        
      
    
    {\displaystyle {\ce {2FeSO_4->[\Delta]Fe_2O_3 + SO_2 + SO_3}}}
  Like other iron(II) salts, iron(II) sulfate is a reducing agent.