At the turn of the 21st century, Valley fever was an obscure fungus in the United States disease with fewer than 3,000 reported cases per year, mostly in California and Arizona. Two decades later, valley fever cases are exploding, increasing more than sevenfold and spreading to other states. And Valley fever is not alone. Fungal diseases generally appear in places where they were not there before, and previously harmless or mildly harmful fungi become deadly to humans. According to scientists, climate change is one of the probable reasons for this deterioration of the fungal situation. Changes in temperature and precipitation are widespread where disease-causing fungi are found; climate-induced disasters can help fungi spread and affect more people; and higher temperatures create opportunities for fungi to evolve into more dangerous disease agents. Fungi have been a neglected group of pathogens for a long time. In the early 2000s, researchers warned that climate change would make bacterial, viral and parasitic infectious diseases such as cholera, dengue fever and malaria more widespread. "But people haven't focused on mushrooms at all," he says Arturo Casadevall , a microbiologist and immunologist at the Johns Hopkins Bloomberg School of Public Health. This is because, until recently, mushrooms did not bother people much. (Shreya Dasgupta).