The virus that took the life of wife has killed three other people in the California city of Mammoth Lakes in Mono County.

The couple were  in their New Mexico home on Feb. 26 — with Betsy’s  HPS is caused by and three similar fatal cases have been reported in one California town.

On Thursday, April 3, the Mono County Health and Human Services Public Health Division  that a third death due to HPS had been reported in the town of Mammoth Lakes. The town is about 330 miles driving distance east from San Francisco.

The Centers for Disease Control and Prevention (CDC) explains on its that people get hantavirus from contact with rodents like rats and mice, “especially when exposed to their urine, droppings, and saliva.” While rare, the virus can also spread through a rodent’s bite or scratch.

Dr. Tom Boo, Mono County Public Health Officer, said he found the latest case involving hantavirus in Mammoth Lakes “tragic and alarming,” and doesn’t understand where the deceased individual would have contacted it from.

He said that while there was no mouse activity in the person’s home, there were some mice in the workplace, but it is “not unusual for indoor spaces this time of year in Mammoth Lakes.”

Boo said that none of the three deceased individuals engaged in activities typically associated with exposure, predicting that they “may have been exposed during normal daily activities, either in the home or the workplace.”

“Many of us encounter deer mice in our daily lives and there is some risk. We should pay attention to the presence of mice and be careful around their waste,” he said.

Symptoms of HPC usually start to show one to eight weeks after contact with an infected rodent, according to the CDC.

Early signs of the disease include fatigue, fever and muscle aches, while half of all HPS patients also go through headaches, dizziness, chills and abdominal pain.

The CDC explains on its website that four to ten days after the initial phase of HPS, “late symptoms” such as coughing and shortness of breath appear.

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Heather Jarrell, New Mexico’s chief medical examiner, announced on Friday, March 7, that Betsy died of HPS. Gene is from a combination of severe heart disease, high blood pressure and 

Being that the was registered on Feb. 17, Jarrell said it is “reasonable to conclude” the actor, who had no food in his stomach at the time of his death, died the following day. He showed no signs of dehydration.

While Betsy was previously thought to have died on Feb. 11, officials discovered that she  shifting the timeline.