12/09/2025
🦟 Rare Diseases Caused by Mosquitoes
Most people know mosquitoes for spreading malaria, dengue, or Zika, but they can also transmit some rare diseases that many people have never heard of. Here are some of them:
• Jamestown Canyon Virus (JCV) – Found mainly in the United States and Canada, spread by Aedes and Culex mosquitoes. It can cause fever, headache, fatigue, and sometimes serious brain inflammation (encephalitis).
• La Crosse Encephalitis – Transmitted by the Eastern treehole mosquito (Aedes triseriatus) in the midwestern and eastern U.S. It usually affects children, causing fever, nausea, and in severe cases, seizures and brain swelling.
• Eastern Equine Encephalitis (EEE) – Spread by Culiseta melanura and other mosquitoes in the eastern U.S. and Caribbean. This is one of the deadliest mosquito-borne diseases, with high fever, neurological damage, and a high fatality rate in severe cases.
• Western Equine Encephalitis (WEE) – Once more common in North and South America, now quite rare. Spread by Culex tarsalis mosquitoes, it causes mild fever but can lead to brain inflammation, especially in infants.
• Rift Valley Fever (RVF) – Occurs mostly in Africa and the Arabian Peninsula. Spread by Aedes and Culex mosquitoes, it causes fever, liver damage, eye problems, and in severe cases, hemorrhage or encephalitis.
• Oropouche Fever – Seen in South and Central America. Carried by Culex quinquefasciatus mosquitoes and midges, it causes fever, headache, muscle pain, and rash, looking very much like dengue.
• Mayaro Virus Disease – Found in the Amazon Basin, spread by forest mosquitoes (Haemagogus). It resembles dengue but with severe joint pain that can last for weeks.
• Tensaw Virus – A rare virus in the southeastern U.S. spread by Culex mosquitoes. Symptoms are usually mild, like a flu-like illness.
• Zika (Severe Form) – Most Zika infections are mild, but in very rare cases it can cause hemorrhage or Guillain-Barré syndrome (a nerve condition).
• Chikungunya (Severe Complications) – Usually causes fever and joint pain, but in rare cases it can cause neurological problems like encephalitis, especially in newborns and older adults.
