High myopia usually describes myopia of −6.00 or more. People with high myopia are more likely to have retinal detachments and primary open angle glaucoma. They are also more likely to experience floaters, shadow-like shapes which appear in the field of vision. In addition to this, high myopia is linked to macular degeneration, cataracts, and significant visual impairment. Age at onset
Myopia is sometimes classified by the age at onset:
Congenital myopia, also known as infantile myopia, is present at birth and persists through infancy. Youth onset myopia occurs in early childhood or teenage, and the ocular power can keep varying until the age of 21, before which any form of corrective surgery is usually not recommended by ophthalmic specialists around the world. School myopia appears during childhood, particularly the school-age years. This form of myopia is attributed to the use of the eyes for close work during the school years. A 2004-2015 Singapore-Sydney study of children of Chinese descent found that time spent on outdoor activities was a factor. Adult onset myopiaEarly adult onset myopia occurs between ages 20 and 40. Late adult onset myopia occurs after age 40. Prevention
Various methods have been employed in an attempt to decrease the progression of myopia, although studies show mixed results. Many myopia treatment studies have a number of design drawbacks: small numbers, lack of adequate control group, and failure to mask examiners from knowledge of treatments used.
Natural influenza infection is a stronger risk factor for the development of GBS than is influenza vaccination and the vaccination reduced the risk of GBS overall by lowering the risk of catching influenza.In the United States, GBS after seasonal influenza vaccination is listed on the federal governments vaccine injury table. On March 24, 2021, after reviewing several post-marketing observational studies, where an increased risk of Guillain–Barré syndrome was observed after 42 days following vaccination with the Zoster vaccine Shingrix, the FDA required safety label changes from the manufacturer GlaxoSmithKline to include warnings for risk of Guillain–Barré syndrome. COVID-19 infection or vaccine related
GBS has been reported in association with COVID-19, and may be a potential neurological complication of the disease. GBS has been reported as a very rare side effect of the Janssen and the Oxford–AstraZeneca COVID-19 vaccine for COVID-19 and European Medicines Agency (EMA) had issued warning to the patients and healthcare providers. The incidence of GBS following the vaccination with the Oxford-AstraZeneca vaccine was originally reported as being lower than the incidence of GBS following a COVID-19 infection. More recent studies, however, found no measurable link between COVID-19 infection and GBS, while correlations with a first dose of AstraZeneca or Janssen vaccines were still positive.COVID-19 has been reported as causing peripheral neuropathy and more recently some evidence of aggravation of autoimmune disorders including GBS. Some studies are now finding Parkinsons Disease is more common in infection survivors.