Incubation Period
Hantavirus has an incubation period ranging from 1 to 8 weeks after exposure, with most people showing symptoms between 2 to 4 weeks. This means an infected person may not feel sick immediately after contact with the virus. During this time, the virus multiplies in the body without causing noticeable symptoms.
Early Stage Symptoms
The first symptoms of hantavirus infection appear suddenly and resemble the flu. These include fever, severe muscle aches, fatigue, headache, and chills. Some people also experience dizziness, nausea, and abdominal pain. These initial symptoms can last for a few days to a week.
Late Stage Symptoms
After the initial phase, symptoms worsen and affect the lungs and heart. People develop a cough, shortness of breath, and chest tightness. As the disease progresses, fluid builds up in the lungs, making breathing extremely difficult. This phase is critical and requires immediate medical attention.
Serious Complications
In severe cases, hantavirus can cause hantavirus pulmonary syndrome, which includes respiratory failure, shock, and organ failure. The mortality rate is about 38 percent among people who develop this severe form. Even survivors may have lasting lung and heart damage.
When to Seek Help
Anyone who experiences fever, muscle aches, and breathing problems after potential exposure to rodents should seek medical care immediately. Early diagnosis and supportive care in a hospital setting, including oxygen therapy and monitoring, improve survival chances significantly. 
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