How To Cure Yeast Infection In Less Than In 24 Hours In Yeast Infection


by JamesTerry - Date: 2010-08-27 - Word Count: 551 Share This!

The name myxovirus was originally applied to influenza viruses. It meant virus with an affinity for mucins. Now there are 2 main groups-the orthomyxoviruses and the paramyxoviruses. All orthomyxoviruses are influenza viruses, isolated strains are named after the virus type (A, B, C), the host and location of initial isolation, the year of isolation and the antigenic designation of the hemagglutinin and neuraminidase. Influenza is an acute respiratory tract infection that usually occurs in epidemics. Three immunologic types of influenza virus are known: A, B, and C. Antigenic changes continually take place within the A group of influenza viruses and to a lesser degree in the B group, whereas influenza C appears to be antigen stable.

The RNA genome consists of 8 distinct pieces with an aggregate molecular weight of 2-4 X 10^6. Due to its divided genome, viruses of this group exhibit several biologic phenomena such as high recombination frequency, multiplying reactivation, and ability to synthesize hemagglutinin and neuraminidase after chemical inactivation of viral infectivity. Human strains of the virus can infect different animals; ferrets are most susceptible senal passage in mice increases its virulence, producing extensive pulmonary consolidation and death. The developing chick embryo readily supports the growth of virus, but there are no gross lesions. Wild influenza viruses do not grow well in tissue cultures. The particle has a lipid-containing envelope covered with spikes; a helical ribonucleoprotein nucleocapsid 18 nm in diameter is enclosed. The RNA is a single molecule. The envelopes of paramyxoviruses are involved in the early interactions between virus and cell. The larger glycoprotein, HN, has neuraminidase and hemagglutinins activities and is responsible for virus adsorption.

This labile paramyxovirus produces a characteristic syncytial effect, the fusion of cells in human cell culture. It is the single most serious cause of bronchiolitis and penumonitis in infants. The particle is slightly smaller (80-120nm) than other paramyxoviruses, and the nucleocapsid measures 11-15nm. RS Virus can be isolated from about 40% of infants under age 6 months suffering from bronchiolitis and from about 25% with pneumonitis, but it is almost never isolated from healthy infants. RS virus infection in older infants and children results in milder presence of specific antibodies), but the resulting symptoms are those of an upper respiratory infection, a "cold". RS virus spreads extensively in children every year during the winter season.

The Coxsackie viruses comprise a large subgroup of the enteroviruses. They produce a variety of illnesses in humans, including aseptic meningitis, herpangina, pleurodynia, hand, foot and mouth disease, myo- and pericarditis, common cold, and possibly diabetes, Coxsackie viruses have been divided into 2 groups; A and B, having different pathogenic potentials for mice. Group A viruses produce widespread myositis in the skeletal muscles of newborn mice, resulting in flaccid paralysis without other observable lesions. Group B viruses may produce focal myositis, encephalitis and most typically, necrotizing steatites involving mainly fetal fat lobules. The genetic makeup of inbred strains determines their susceptibility to Coxsackie B viruses. Virus has been recovered from the blood in the early stages of natural infection in humans and of experimental infection in Chimpanzees. Virus is also found in the throat for a few days early in the infection and in the stools for up to 5-6 weeks. The distribution of virus is similar to that found with the other enteroviruses.

Related Tags: influenza disease, human influenza, syncytial virus, herpangina

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