WOODLAND, Calif. - The death of a 41-year-old Woodland man from the hantavirus - a rare but frequently fatal virus spread by rodents - is being investigated by the state Department of Health Services into the source of his infection.
Alfonso Alvarado died on April 24 of pneumonia in a Sacramento hospital. Subsequent tests revealed he suffered from hantavirus pulmonary syndrome, Yolo County Public Health Officer Bette Hinton said Monday.
It is the first reported case in Yolo and Sacramento counties.
Hantavirus pulmonary syndrome is a serious respiratory disease with a mortality rate of nearly 43 percent and no known cure. It is found mostly in rural and mountain areas.
Of 29 documented cases in the state, many were concentrated in the eastern Sierras, an area that Alvarado had not recently visited.
Alvarado hauled hay throughout the state, and health officials will start next week checking the farms and race tracks he visited to find the rodents carrying the virus. Investigators will search in several counties, including Colusa, Imperial, Los Angeles, Monterey, Sacramento, Santa Cruz, San Diego and Yolo counties.
Health warnings will be issued in areas where the hantavirus is found.
The virus is spread from wild rodents, usually deer mice, to people through the air. The virus gets into the air as mist from urine and saliva or dust from feces. People also can become infected by touching the mouth or nose after handling contaminated material or from a rodent's bite.
Neither the common house mouse nor rats have been linked to hantavirus pulmonary syndrome, Hinton said.
Hinton said an earlier diagnosis might not have prevented his death because there is no cure. Doctors can only offer an infected person ''supportive treatment,'' such as help with breathing, while the body's immune system battles the virus.
The hantavirus strain was first discovered in 1993, when it killed 10 people in New Mexico. Recently biologists have identified a 22-year-old man who died from hantavirus infection in 1980, showing the virus may not be as new as once thought.