Final answer:
Encephalitis is mostly caused by viral infections, not bacteria, and can lead to brain swelling and injury. The most common viruses causing encephalitis include eastern equine encephalitis and West Nile encephalitis. Arboviruses transmitted by mosquitoes are typical pathogens that lead to arboviral encephalitis.
Step-by-step explanation:
The statement "Encephalitis occurs because of a severe bacterial infection" is false. Encephalitis is an inflammation of the brain, which is most often caused by viral infections, not bacterial ones. While rare types of encephalitis may be caused by bacteria, the most common forms are due to viruses such as eastern equine encephalitis, western equine encephalitis, West Nile encephalitis, and Japanese encephalitis. Symptoms can include fever, headache, drowsiness, and confusion. The immune system's response to fight the infection can sometimes cause swelling in the brain, leading to potential brain injury or even death if not properly treated. Various arboviruses can cause different types of arboviral encephalitis, and these are often transmitted by mosquitoes.