Cryptococcosis is a disease caused by the yeast-like fungus, Cryptococcosis neoformans. The fungus is found frequently in the environment, particularly in pigeon droppings, nesting places and soil, especially if it is contaminated with pigeon faeces. It has also been associated with certain species of eucalyptus trees. Therefore, exposure to the fungus is common and it is believed that humans have a high natural resistance to infection. People who have disorders of immunity have less resistance and are more susceptible to developing the disease. Naturally acquired cryptococcosis occurs in humans and in animals although there is no evidence of transmission from animals to humans. Cryptococcal meningitis, if untreated, is fatal within weeks to months.
Cryptococcosis most commonly causes meningitis but may also infect the lungs, kidneys, prostate and bone. The main symptoms are fever, tiredness and headache. Most infections develop slowly with symptoms usually present for two to four weeks prior to diagnosis.
It is thought that the infection is spread by inhalation of the organism. The disease is not transmitted directly from person to person.
The time from exposure to the organism and the development of disease is not known. However lung disease may precede brain infection by months or years.
Antifungal agents are required to treat the disease. All cases require treatment, which is generally continued for an extended period. In people with HIV/AIDS and people with weakened immune systems, cryptococcal infection is rarely cured and requires ongoing treatment to control the disease.
The fungus that causes cryptococcosis is known to be present in pigeon droppings. Therefore it is recommended that if large accumulations of droppings are to be removed they should first be made wet in order to reduce the likelihood of inhaling the fungus.
There are no specific measures to control the spread of the disease particularly as cryptococcosis rarely occurs in clusters in the same area and is rarely a danger to healthy people.