Sometimes, as in the Great Irish Famine of 1845–1849, fungal diseases of plants, in this case potato blight caused by Phytophthora, result in large-scale human suffering. Fungi are similarly the main cause of economic losses of timber in buildings. Finally, fungi cause many diseases of humans and livestock; Aspergillosis kills some 600,000 people a year, mainly however those with already weakened immune systems.