In many northern or temperate regions like Michigan's Upper Peninsula, mosquitoes have long been seen as a minor summer annoyance. But recent years have brought a shift: mosquito-borne illnesses are on the rise, even in areas with historically shorter seasons. Warmer weather, increased rainfall, and the migration of mosquito species are creating a new reality for public health. 
 
Understanding what’s behind the trend and how to protect your family is critical during the warmer months. 

What’s Behind the Increase? 

1. Longer, Warmer Seasons 
Due to shifting climate patterns, regions like Michigan's Upper Peninsula are experiencing longer warm seasons. This creates more time for mosquitoes to hatch, feed, and transmit disease. 
 
2. Increased Rain and Standing Water 
More frequent storms and heavier rains contribute to standing water accumulation, especially in urban areas. Anything from clogged gutters to toys left in the yard can become a mosquito nursery. 
 
3. Expanding Mosquito Habitats 
Southern mosquito species like Aedes aegypti are migrating north. These mosquitoes thrive in urban and suburban environments and are capable of transmitting dengue, Zika, and chikungunya. 
 
4. Travel-Related Transmission 
People traveling to tropical regions may unknowingly bring mosquito-borne viruses home. Local mosquitoes can then bite infected individuals and pass the virus to others. 
 

Mosquito-Borne Illnesses Seen in Michigan's Upper Peninsula

• West Nile Virus: The most common in northern states. Severe infections may lead to encephalitis or meningitis. 
• Eastern Equine Encephalitis: Rare but very serious. Found near wetlands and wooded areas. 
• La Crosse Encephalitis: Found in wooded, rural areas and often affects children. 
• Zika and Dengue: Rare locally but possible due to returning travelers. 
  

How to Protect Yourself 

• Use Insect Repellent: Look for EPA-registered repellents and apply them before outdoor activities. 
• Remove Standing Water: Walk your yard weekly to remove any items that collect rain — such as flowerpots, tarps, and even bottle caps. 
• Dress Smart: Opt for long sleeves and pants when outdoors during peak mosquito hours. 
• Screen Your Home: Keep doors and windows sealed and screens in good repair. 
• Be Travel-Smart: Use extra caution when visiting tropical areas. Pack repellent and check CDC travel advisories. 
  

Who Is at Greater Risk? 

Certain groups are more likely to experience complications: 

• Infants and children 
• Older adults
• Pregnant individuals 
• People with underlying conditions or compromised immunity 
  

Watch for Symptoms 

Common signs of mosquito-borne illness include fever, rash, headache, nausea, joint pain, or fatigue. Seek medical attention if symptoms appear within days of a mosquito bite. 

Stay Safe with UP Health System

The team at UP Health System is here to support you with prevention tips, care when you need it and up-to-date local information. We’re committed to keeping our community safe and healthy — every season. 

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