Expert warns: "There is a more severe form of the Andes hantavirus, and it has been spreading for a long time"

“Symptoms of the Andes strain of hantavirus can appear as early as two days after exposure to the virus, and the longest recorded incubation period is 42 days,” Simpson said.

The virus is most commonly transmitted between humans through bodily fluids, especially through coughing once an infected person begins to become ill. Kissing and sexual contact can also transmit the virus.

The virus can remain in the air and spread during prolonged stays in an enclosed space with an infected person, such as sleeping in the same bed or staying in the same room, even without direct physical contact, Simpson said.

The virus can replicate in the salivary glands, and is therefore spread through tiny droplets produced when people cough, sneeze, or even breathe.

“People infected with the Andes strain of the virus are contagious for a day or two. It appears that this begins when they develop the first symptoms,” he said.

Symptoms include common signs of viral infection such as fever, body aches, chills, vomiting, and diarrhea, according to Kansas health authorities.

A few days after the onset of initial symptoms, people may develop a severe respiratory illness known as hantavirus pulmonary syndrome, causing cough, chest tightness, and difficulty breathing, which can be fatal.

There is also no specific treatment, and care is based on supporting the patient during the illness.

Does the virus mutate?

Viruses mutate, that is, they adapt as they spread, but Simpson says this only happens when the virus passes through a large number of infected individuals over a long period of time.

‘The key point is that it takes many generations of transmission for a virus to mutate into something that poses a serious threat,’ Simpson said.

‘So far, that has never happened. If anything, the virus seems to become somewhat weaker with each transmission. The highest number of consecutive hantavirus transmissions ever documented was four generations, after which the virus disappeared. This could have happened for various reasons, such as the infected person staying at home and not further spreading the virus,’ he said.

Because of all this, as well as the fact that Kansas health authorities and local officials are closely monitoring the situation, Simpson believes that the Andes strain hantavirus outbreak currently does not pose a serious threat to public health.