September 6, 2002
Cryptococcal disease is a rare fungal infection that can affect the
lungs and nervous system. In some cases, the infection can lead to swelling
of the lining of the brain. The infection is caused by exposure to the
spores of the cryptococcus fungus and can be successfully treated with
anti-fungal medication.
The disease and the cryptococcus fungus
appear across the world. Most people are thought to be exposed to some
variety of the fungus at some point in their life but never develop serious
symptoms.
Prior to 1999, British Columbia reported an
average of two or three cases annually of cryptococcal disease.
Historically, British Columbia cases were the result of exposure to the
neoformans variety of cryptococcus fungus. Since 1999, more than 50 cases,
including one fatality, have been reported by residents of, or visitors to,
Vancouver Island. Cases have been reported in various places on the island's
east coast.
These recent cases were the result of
exposure to the gattii variety of cryptococcus fungus. The gattii variety is
more commonly found in tropical and sub-tropical regions of the world and
has been found growing on trees in those regions.
The BC Centre for Disease Control is leading
an investigation into the increased level of cases of cryptococcal disease
on Vancouver Island. This investigation identified Rathtrevor Beach
Provincial Park in Parksville as a common feature among a small number of
cases. Environmental samples taken from the park found cryptococcus fungus
of the gattii variety in the soil and air and growing on Douglas-Fir and
alder trees. Samples taken from MacMillan Provincial Park, which has not
been linked to any reported cases, found the fungus growing on a cedar tree.
MacMillan Provincial Park (Cathedral Grove) is located between Parksville
and Port Alberni.
The BC Centre for Disease Control advises
the public and doctors to be aware of the symptoms of cryptococcal disease
as the gattii variety of fungus is expected to be found growing on trees
elsewhere on Vancouver Island. The investigation and testing continues and
the public will be advised accordingly.
The risk of contracting the disease remains
low. Including the recent cases, less than 3 cases are reported per 100,000
people per year on Vancouver Island.
The disease also affects animals, although
in different ways than it affects people. Since 2000, more than 35 cases of
infection have been reported on Vancouver Island among dogs, cats, llamas, a
ferret and wild porpoises.
Contact:
Dr. Murray Fyfe, BC Centre for Disease Control, 604 660-3199
Dr. Perry Kendall, Provincial Health Officer, 250 952-0876