Viral Diseases ,Symptoms ,complications

 Introduction

A virus is composed of nucleic acid, either DNA or RNA, surrounded by a protein coat. It requires a living cell in which to multiply. A virus is a small infectious organism much smaller than a fungus or bacterium that must invade a living cell to reproduce (replicate). The virus attaches to a cell (called the host cell), enters the cell, and releases its DNA or RNA inside the cell. This can affect brain, skin and other systems. Research reveals that viruses are implicated in many cancers as well.

Definition of Viral Infection:

A viral disease (or viral infection, or infectious disease) occurs when an organism's body is invaded by pathogenic viruses, and infectious virus particles
(virions) attach to and enter susceptible cells.

Types of viral infections:

*Probably the most common viral infections are:

  1/ Respiratory Viral Infections ( Respiratory viral infections affect the lungs, nose, and throat )

 2 / Viral Diseases of the Nervous System 

 3 / Viral Skin Infections ( can range from mild to severe and often produce a rash )

 4 / Viruses are one of the most common causes of food poisoning

 5 / Sexually Transmitted Viral Infections 

Methods of Virus Transmission

*Viruses can be transmitted in a variety of ways:

• Breathing in air-borne droplets contaminated with a virus

• Eating food or drinking water contaminated with a virus

• Having sexual contact with a person who is infected with a sexually transmitted virus

• Sharing contaminated needles and Spread during transfusion of contaminated blood

• Indirect transmission from person to person by a virus host, such as a mosquito, tick, or field mouse act as "vectors, "

• Touching surfaces or body fluids contaminated with a virus

• Touching infected feces or body fluids and not washing your hands before eating or touching your mouth, eyes or nose

•  Transmission of a virus from an infected mother to her baby during pregnancy or delivery

Symptoms :

Symptoms of viral diseases vary depending on the specific type of virus causing infection, the area of the body that is infected, the age and health history of the patient, and other factors. The symptoms of viral diseases can affect almost any area of the body or body system. Symptoms of viral diseases can include:

•  Flu-like symptoms (fatigue, fever, sore throat, headache, cough, aches and pains)

•  Gastrointestinal disturbances, such as diarrhea, nausea and vomiting

•  Irritability

•  Malaise (general ill feeling)

•  Rash

•  Sneezing

•  Stuffy nose, nasal congestion, runny nose, or postnasal drip

•  Swollen lymph nodes

•  Swollen tonsils

•  Unexplained weight loss

• Serious symptoms that might indicate a life-threatening condition In some cases, viral diseases can result in serious complications, such as dehydration or pneumonia or have any of the following symptoms:

•  Change in alertness or level of consciousness

•  Chest pain

•  Deep, wet chest cough that produces yellow, green or brownish phlegm

•  High fever (higher than 101 degrees Fahrenheit)

•  Lethargy or unresponsiveness

•  Seizure

•  Shortness of breath, wheezing, or difficulty breathing

•  Stiff neck

• Yellowing of the skin and whites of the eyes (jaundice)

Possible complications of viral diseases:

*In some people, viral diseases can break down the body's defenses and lead to more serious infections and life-threatening complications including:

•  Acute bronchitis

•  Cervical cancer (from human papillomavirus infection)

•  Dehydration

•  Frequent life-threatening, opportunistic infections

• Otitis media (ear infection)   Pneumonia

•  Secondary bacterial infection

•  Seizures   Shock and coma

•  Sinusitis

•  Worsening of asthma