Which body organs are most adversely affected by encephalitis viruses transmitted by mosquitoes?

• A. Central nervous system
• B. Lungs
• C. Liver
• D. Kidneys

Answer: (A)

Encephalitis viruses carried by mosquitoes primarily attack the brain and spinal cord. These neurotropic viruses enter the bloodstream after a mosquito bite and can cross the blood–brain barrier, infecting neurons and supporting cells in the central nervous system. The inflammation that results—encephalitis—produces neurological signs such as severe headache, confusion, seizures, or even coma. While a severe infection can affect other organs, the defining and most harmful involvement is in the central nervous system, so that is the best answer. Lungs, liver, and kidneys aren’t the primary targets of these viruses, though they can be affected indirectly in very ill patients.