tailieunhanh - Chapter 186. Rubella (German Measles)

Rubella is an acute viral infection of children and adults that characteristically includes rash, fever, and lymphadenopathy and has a broad spectrum of other possible manifestations. However, a high percentage of rubella infections in both children and adults are subclinical. In addition, the illness can resemble a mild attack of measles (rubeola) and can cause arthritis, especially in adults. Rubella was formerly known as German measles because it was first distinguished clinically from rubeola in Germany, where it generated much medical interest in the mideighteenth and early nineteenth centuries. Rubella during pregnancy can lead to fetal infection, with the. | Chapter 186. Rubella German Measles Definition Rubella is an acute viral infection of children and adults that characteristically includes rash fever and lymphadenopathy and has a broad spectrum of other possible manifestations. However a high percentage of rubella infections in both children and adults are subclinical. In addition the illness can resemble a mild attack of measles rubeola and can cause arthritis especially in adults. Rubella was formerly known as German measles because it was first distinguished clinically from rubeola in Germany where it generated much medical interest in the mideighteenth and early nineteenth centuries. Rubella during pregnancy can lead to fetal infection with the production of a significant constellation of malformations congenital rubella syndrome in a high proportion of infected fetuses. Rubella virus was first isolated in cell culture just before the last pandemic of the disease began in 1962. Since the licensing of rubella vaccine in the United States in 1969 there have been no further epidemics in this country. Etiologic Agent Rubella virus a togavirus is the only member of the Rubivirus genus and is closely related to the alphaviruses. Unlike these agents however it does not require a vector for transmission. Moreover there is no RNA sequence homology between rubella virus and the alphaviruses. The rubella virion is composed of an inner icosahedral capsid of RNA and protein that is surrounded by a lipid-containing envelope with glycoprotein spikes and a diameter of 60 nm. The structural proteins associated with rubella virus are E1 and E2 transmembrane envelope glycoproteins and C the capsid protein that surrounds the viral RNA . Only one serotype has been identified. Epidemiology In the United States during the prevaccine era rubella was most common in the spring and most often affected school-age children only 80-90 of adults were immune and major epidemics occurred every 6-9 years. The most recent epidemic in the United