Most British road traffic lights are mounted vertically on a black rectangle with a white border (forming a "sighting board") so drivers can more easily look for the position of the light. In the eastern provinces of Canada traffic lights are sometimes differentiated by shape in addition to color: square for red, diamond for yellow, and circle for green (see included image of horizontal traffic light from Nova Scotia). Piloting aircraft
Although many aspects of aviation depend on color coding, only a few of them are critical enough to be interfered with by some milder types of color blindness. Some examples include color-gun signaling of aircraft that have lost radio communication, color-coded glide-path indications on runways, and the like. Some jurisdictions restrict the issuance of pilot credentials to persons with color blindness for this reason. Restrictions may be partial, allowing color-blind persons to obtain certification but with restrictions, or total, in which case color-blind persons are not permitted to obtain piloting credentials at all.In the United States, the Federal Aviation Administration requires that pilots be tested for normal color vision as part of their medical clearance in order to obtain the required medical certificate, a prerequisite to obtaining a pilots certification.
Prognosis
Identification of poor prognostic factors include cerebral edema, status epilepticus, and thrombocytopenia. In contrast, a normal encephalogram at the early stages of diagnosis is associated with high rates of survival. Epidemiology
The number of new cases a year of acute encephalitis in Western countries is 7.4 cases per 100,000 people per year. In tropical countries, the incidence is 6.34 per 100,000 people per year. The number of cases of encephalitis has not changed much over time, with about 250,000 cases a year from 2005 to 2015 in the US. Approximately seven per 100,000 people were hospitalized for encephalitis in the US during this time. In 2015, encephalitis was estimated to have affected 4.3 million people and resulted in 150,000 deaths worldwide. Herpes simplex encephalitis has an incidence of 2–4 per million of the population per year. Terminology
Encephalitis with meningitis is known as meningoencephalitis, while encephalitis with involvement of the spinal cord is known as encephalomyelitis.The word is from Ancient Greek ἐγκέφαλος, enképhalos "brain", composed of ἐν, en, "in" and κεφαλή, kephalé, "head", and the medical suffix -itis "inflammation". See also
References
Further reading
External links
WHO: Viral Encephalitis