Michigan confirms first known human case of hantavirus

SOUTHFIELD, Mich. (FOX 2) - The state of Michigan says it has confirmed the first case of hantavirus, a disease passed from rodents to humans, in a woman who was cleaning a vacant home in Washtenaw County.

According to the Michigan Department of Health and Human Services (MDHHS), the state's first confirmed human case of Sin Nombre hantavirus was detected in the state. The MDHHS said the woman who tested positive was likely exposed when she was cleaning an unoccupied dwelling that had signs of an active rodent infestation. The Sin Nombre virus is spread by the deer mouse and white-footed mouse.

Hantavirus was first found in the southwest part of the United States in 1993. The virus causes the hantavirus pulmonary syndrome (HPS) and, since it was first discovered, has been found to infect people throughout the United States and Americas.

The MDHHS said the woman was hospitalized with a serious pulmonary illness but did not state her current condition.

Rodents carry hantavirus and humans are infected when freshly dried contaminated droppings is disturbed and inhaled. It then enters the skin or on mucous membranes when drinking or eating. It can also be transmitted by bites from rodents. The highest risk of exposure happens when entering or cleaning rodent-infested structures.

"HPS is caused by some strains of hantavirus and is a rare but severe and sometimes fatal respiratory disease that can occur one to five weeks after a person has exposure to fresh urine, droppings or saliva from infected rodents," said Dr. Joneigh Khaldun, chief medical executive and chief deputy for health at MDHHS. "Anyone who comes into contact with rodents that carry hantavirus is at risk for HPS and healthcare providers with a suspect case of hantavirus should contact their local health department to report the case and discuss options for confirmatory testing."

There is no evidence that hantavirus can be passed person-to-person.

Symptoms of HPS can include fever, chills, body aches, headache and gastro-intestinal signs such as nausea, vomiting, diarrhea and abdominal pain. The illness can progress to include coughing and shortness of breath. 

It has a fatality rate of 40%.

How to prevent spreading Hantavirus

Because hantavirus spreads in mouse and rat urine and droppings, you should wear rubber or plastic gloves when cleaning up after signs of a possible rodent infestation.

You should also spray the droppings with a disinfectant or mixture of bleach and water. Get them VERY wet and let them soak for 5 minutes. Then use a paper towel to wipe them up and throw it in the garbage. Then seal the trash bag and put it in another trash bag and dispose of it in a trash can that is regularly emptied.

DO NOT sweep or vacuum mouse or rate urine, droppings, or nrests. This sends virus particles into the air where it's more like to be breathed in.

Once you're done cleaning up, wash your gloved hands with water or spray them with a disinfectant. Then take them off and throw them away. Then wash your hands with soap and water again.

"We can prevent and reduce the risk of hantavirus infection by taking precautions and being alert to the possibility of it," says Dr. Juan Luis Marquez, medical director with Washtenaw County Health Department. "Use rubber, latex, vinyl or nitrile gloves when cleaning areas with rodent infestations, ventilate areas for at least 30 minutes before working, and make sure to wet areas thoroughly with a disinfectant or chlorine solution before cleaning."

Hantaviruses are viruses and are susceptible to most disinfectants (diluted chlorine solutions, detergents, general purpose household disinfectants including those based on phenols, quaternary ammonium compounds and hypochlorite). Depending on environmental conditions, these viruses probably survive less than one week in indoor environments and much shorter periods (hours) when exposed to sunlight outdoors. Special precautions should be taken when cleaning up after rodents. In cases of heavy rodent infestation, it is recommended to consult with a pest-control professional.

How is Hantavirus different from Coronavirus?

The signs and symptoms of both the Hantavirus and Coronavirus (COVID-19) are the very similar - fever, fatigue, coughing, shortness of breath, and muscle pains - are all the most common symptoms of both viruses. They both also have similar additional symptoms including headaches and vomiting and diarrhea. 

But additional symptoms of the hantavirus include dizziness, chills, nausea, and abdominal pain.

The incubation of hantavirus is much longer at 7 to 60 days.

Unlike COVID-19, Hantavirus cannot be transmitted person-to-person.

On average, there are about 20 to 40 cases of hantavirus in the U.S., typically in the west portion of the country. Cases are reported year-round but typically peak in the spring and summer months.