Primary<unk>  infection results in chickenpox<unk> , which may result in complications including encephalitis, pneumonia (either direct viral pneumonia or secondary bacterial pneumonia), or bronchitis (either viral bronchitis or secondary bacterial bronchitis). Even when clinical symptoms of chickenpox have resolved,<unk>  remains dormant in the nervous system of the infected person (virus latency), in the trigeminal and dorsal root ganglia.<unk>  enters through the respiratory system. Having an incubation period of 10–21 days, averaging at 14 days. Targeting the skin and peripheral nerve, the period of illness is from 3 to 4 days. 1–2 days before the rash appears is when this virus is the most contagious. Signs and symptoms include vesicles that fill with pus, rupture, and scab before healing. Lesions most commonly occur on the face, throat, the lower back, the chest and shoulders. In about a third of cases,<unk>  reactivates later in life, producing a disease known as shingles or herpes<unk> . The individual lifetime risk of developing herpes<unk>  is thought to be between 20% and 30%, or approximately 1 in 4 people. However, for individuals aged 85 and over, this risk increases to 1 in 2 people. In a study from Sweden by Nilsson et al (2015) the annual incidence of herpes<unk>  infection is estimated at a total of 315 cases per 100,000 inhabitants for all ages and 577 cases per 100,000 for people 50 years of age or older.<unk>  can also infect the central nervous system, with a 2013 article reporting an incidence rate of 1.02 cases per 100,000 inhabitants in Switzerland, and an annual incidence rate of 1.8 cases per 100,000 inhabitants in Sweden. Shingles lesions and the associated pain, often described as burning, tend to occur on the skin that is innervated by one or two adjacent sensory nerves, almost always on one side of the body only. The skin lesions usually subside over the course of several weeks, while the pain often persists longer. In 10 to 15% of cases, the pain persists more than three months, a chronic and often disabling condition known as postherpetic neuralgia. Other serious complications of<unk><unk>  infection include Mollaret's meningitis,<unk>  multiplex, and inflammation of arteries in the brain leading to stroke, myelitis, herpes ophthalmicus, or<unk>  sine herpete. In Ramsay Hunt syndrome,<unk>  affects the geniculate ganglion giving lesions that follow specific branches of the facial nerve. Symptoms may include painful blisters on the tongue and ear along with one sided facial weakness and hearing loss. If infected during initial stages of pregnancy severe damage to the fetus can take place. Reye’s syndrome can happen after initial infection, causing continuous vomiting and signs of brain dysfunction like extreme drowsiness or combative behavior. In some cases, death or coma can follow. Reye’s syndrome mostly affects children and teenagers, using aspirin during infection can increase this risk.
Varicella zoster virus
Mumps virus
Coxsackie B4 virus
Venezuelan equine encephalitis virus
Coxsackie B virus
Hendra virus
Western equine encephalitis virus
Cricket paralysis virus