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Immunologically, the mostsignificant surface proteins include hemagglutinin (H) and neuraminidase (N). Hemagglutinin and neuraminidase are criticalfor virulence, and they are major targets for the neutralizing antibodies of acquired immunity to influenza. Hemagglutinin binds to respiratory epithelial cells, allowing cellular infection. Neuraminidase cleaves the bond that holds newlyreplicated virions to the cell surface, permitting the infection to spread.Uncomplicated influenza illness typically resolves after 3—7 days for the majority of persons, although cough and malaise canpersist for >2 weeks. However, influenza virus infections can cause primary influenza viral pneumonia; exacerbate underlying medical conditions (e.g., pulmonary or cardiac disease), lead to secondary bacterial pneumonia, sinusitis, or otitis media; or contribute to coinfections with other viral or bacterial pathogens. Influenza virus infection also has been uncommonly associated with encephalopathy, transverse myelitis, myositis, myocarditis, pericarditis, and Reye syndromeMeaslesProdrome of fever (as high as 105), malaise, cough, coryza, and conjunctivitis (the three c’s), a pathognomic exanthema (koplik spots), followed by a The cause of measles is the measles virus, a single-stranded, negative-sense enveloped RNA virus of the genus Morbilliviruswithin the family Paramyxoviridae.Patient is contagious from 4 days before the rash appears until 4 days after the rash appears. Some immunocompromised patients do not develop the rash. Acute encephalitis can occur. Otitis media, bronchopneumonia, laryngotracheobronchitis, and
maculopapular rash, Rash appears about 14 days after exposure. The rash spreads from the head to the trunk t the lower extremities.diarrhea.One out of every 1,000 measles cases will develop acute encephalitis, which often results in permanent brain damage.One or two out of every 1,000 children who become infected with measles will die from respiratory and neurologic complications.Subacute sclerosing panencephalitis (SSPE) is a rare, but fatal degenerative disease of the central nervous system characterized by behavioral and intellectual deterioration and seizures that generally develop 7 to 10 years after measles infection.c.Analyze the HIV viral structure, the process by which it infects the CD4 cells and viral replication and describe:HIV belongs to a group of retroviruses called lentiviruses. The genome of retroviruses is made of RNA (ribonucleic acid), and each virus has two single chainsof RNA; for replication, the virus needs a host cell, and the RNA must first be transcribed into DNA (deoxyribonucleic acid), which is done with the enzyme reverse transcriptase. HIV infects mainly the CD4+ lymphocytes(T cells), but also to a lesser degree monocytes, macrophages, and dendritic cells (these cells are also CD4+ cells). Once infected, the cell turns into an HIV-replicating cell and loses its function in the human immune system. Like other viruses, HIV does not have a cell wall or a nucleus. The basic structure of the virus is as follows: