How quickly do most persons infected with Eastern Equine Encephalitis Virus (EEEV) show severe symptoms?

Individuals infected with Eastern Equine Encephalitis Virus (EEEV) typically start to show severe symptoms within 48 hours after the onset of the infection. The virus can lead to significant neurological disease, and once symptoms appear, they can escalate quickly, often resulting in encephalitis. The rapid progression of symptoms is a characteristic feature of EEEV infection, making it a serious concern for public health due to its potential for severe and rapid illness.

In contrast, while symptoms can begin to manifest within a day or two, they do not usually appear within just 24 hours, as the incubation period for EEEV can be longer. Symptoms emerging within a week is possible but is generally too slow a progression for a typical acute EEEV infection, and the notion that individuals never show symptoms is inaccurate, as many cases do indeed present with significant clinical manifestations.