Coronary Artery Surger

 

 

Surgical of CAD

 

 

Varicose Veins

 

 

Chest Trauma

 

 

Influenza viruses’: structure, replication, modes of
transmission, Types of infection, treatment,
complications, and preventive measures.

by Mohammad Jamel Salim; RN,MSc in clinical biochemistry
Nursing supervisor, Specialty Hospital.

Influenza Virus Properties
Belongs to the genus orthomyxovirus in the family of Orthomyxoviridae. ssRNA enveloped viruses with a helical symmetry.Enveloped particles 80-120nm in diameter.

A virus consists of a package of genetic material surrounded by a protein and lipid shell. The type A influenza virus -- the family to which the new, closely watched strain of bird flu belongs -- consists of 10 proteins and eight strands of ribonucleic acid (RNA), which carry the code for making the proteins.

The RNA is closely associated with the nucleoprotein (NP) to form a helical structure.

The genome is segmented, with 8 RNA fragments (7 for influenza C) There are 4 antigens present, the haemagglutinin (HA), neuraminidase (NA), nucleocapsid (NA), the matrix (M) and the nucleocapsid proteins. The NP is a type-specific antigen which occurs in 3 forms, A, B and C, which provides the basis for the classification of human influenza viruses. The matrix protein (M protein) surrounds the nucleocapsid and makes up 35- 45% of the particle mass.

2 surface glycoproteins are seen on the surface as rod-shaped projections. The haemagglutinin (HA) is made up of 2 subunits, HA1 and HA2. HA mediates the attachment of the virus to the cellular receptor. Neuraminidase molecules are present in lesser quantities in the envelope.