Deadly Virus Blamed on Fungi Offspring
Vancouver (Canada):
In the mysterious world of the fungus, not only are there same-sex relationships, they produce offspring.
And such free-wheeling sexual activity is being blamed for the outbreak of a virulent, rare fungus that began in 1999 on Vancouver Island, has already caused four deaths, infected scores of others and appears to have spread to the Lower Mainland.
A paper published yesterday in the journal Nature argues that the severe new strain -- cryptococcus gattii -- is the result of sexual reproduction between two types of a similar species of fungi, despite the fact that both were of the same sex.
Joseph Heitman, a microbiologist at Duke University in North Carolina and a principal author of the study, said the finding may lead to a greater understanding of potentially deadly influenza pandemics.
"What human pathogens want to do is survive and reproduce," he explained, in an interview. "If you think about how influenza viruses arise, at the root of it is a sexual event."
Prof. Heitman said the viruses re-arrange their genetic makeup "and suddenly a recombinant arises that can be transmitted from birds to humans, human to human, and then all of a sudden, there is a pandemic."
He said this mixing of ancestral species gives rise to unique descendants, and they are much more virulent than earlier strains, as in the 1999 outbreak on Vancouver Island.
The outbreak was first identified among visitors to Rathrevor Provincial Park north of Nanaimo, but since then strains of the infectious fungus have been found on the Island as far north as Courtenay and as far south as Victoria.
Earlier this year, the B.C. Centre for Disease Control reported several people and six animals on the Mainland had been infected by cryptococcal disease caused by the same rare fungus, cryptococcus gattii.
The fungus can cause a life-threatening infection of the lungs and central nervous system, although getting the disease is so uncommon that the general public is not considered to be in danger.
"This has been going on for six years now and it's pretty unprecedented," Prof. Heitman said. "There haven't been any outbreaks like this [fungus] before."
The deadly fungus is similar to a tropical fungus previously found only in Australia.
Oct 10, 2005
Rod Mickleburgh
Vancouver (Canada):
In the mysterious world of the fungus, not only are there same-sex relationships, they produce offspring.
And such free-wheeling sexual activity is being blamed for the outbreak of a virulent, rare fungus that began in 1999 on Vancouver Island, has already caused four deaths, infected scores of others and appears to have spread to the Lower Mainland.
A paper published yesterday in the journal Nature argues that the severe new strain -- cryptococcus gattii -- is the result of sexual reproduction between two types of a similar species of fungi, despite the fact that both were of the same sex.
Joseph Heitman, a microbiologist at Duke University in North Carolina and a principal author of the study, said the finding may lead to a greater understanding of potentially deadly influenza pandemics.
"What human pathogens want to do is survive and reproduce," he explained, in an interview. "If you think about how influenza viruses arise, at the root of it is a sexual event."
Prof. Heitman said the viruses re-arrange their genetic makeup "and suddenly a recombinant arises that can be transmitted from birds to humans, human to human, and then all of a sudden, there is a pandemic."
He said this mixing of ancestral species gives rise to unique descendants, and they are much more virulent than earlier strains, as in the 1999 outbreak on Vancouver Island.
The outbreak was first identified among visitors to Rathrevor Provincial Park north of Nanaimo, but since then strains of the infectious fungus have been found on the Island as far north as Courtenay and as far south as Victoria.
Earlier this year, the B.C. Centre for Disease Control reported several people and six animals on the Mainland had been infected by cryptococcal disease caused by the same rare fungus, cryptococcus gattii.
The fungus can cause a life-threatening infection of the lungs and central nervous system, although getting the disease is so uncommon that the general public is not considered to be in danger.
"This has been going on for six years now and it's pretty unprecedented," Prof. Heitman said. "There haven't been any outbreaks like this [fungus] before."
The deadly fungus is similar to a tropical fungus previously found only in Australia.
Oct 10, 2005
Rod Mickleburgh
