Viral Diseases
By Aaditya Gurung XI-B
Definition of viral
diseases
1. Viruses are very small infectious agents. They’re made up of a
piece of genetic material, such as DNA or RNA, that’s enclosed in a
coat of protein.
2. Viruses invade cells in your body and use components of those
cells to help them multiply. This process often damages or destroys
infected cells.
3. A viral disease is any illness or health condition caused by a
virus.
4. Viral diseases are extremely widespread infections caused by
viruses, a type of microorganism. There are many types of viruses
that cause a wide variety of viral diseases. The most common type
of viral disease is the common cold, which is caused by a viral
infection of the upper respiratory tract (nose and throat). Other
common viral diseases include:
Chickenpox
Flu (influenza)
Human immunodeficiency virus (HIV/AIDS)
Human papillomavirus (HPV)
Infectious mononucleosis
Mumps, measles and rubella
Shingles
Viral gastroenteritis (stomach flu)
Viral hepatitis
Viral meningitis
Viral pneumonia
Means of spread
Viral diseases are contagious and spread from person to
person when a virus enters the body and begins to
multiply. Common ways that viruses spread from person
to person include:
•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.
•Indirect transmission from person to person by a virus host, such
as a mosquito, tick, or field mouse.
•Touching surfaces or body fluids contaminated with a virus.
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
In infants, signs of a viral disease can also include:
•Bulging of the soft spot on the top of the head
•Difficulty with feeding
•Excessive crying or fussiness
•Excessive sleepiness
In some cases, viral diseases can result in serious complications, such
as dehydration or pneumonia. Seek immediate medical care if you, or
someone you are with, have any of the following symptoms:
•Change in alertness or level of consciousness
•Deep, wet chest cough that produces yellow, green or brownish phlegm
•High fever (higher than 101 degrees Fahrenheit)
•Lethargy or unresponsiveness
•Shortness of breath, wheezing, or difficulty breathing
Stiff neck
•Yellowing of the skin and whites of the eyes (jaundice)
Precautions
•Always keep your hands clean.
•Avoid touching your nose, eyes and mouth with unwashed hands.
The nose, eyes and mouth are entry sites for viruses and bacteria.
•Avoid touching your nose, eyes and mouth. These are entry points
for viruses and bacteria.
•Avoid contact with people that are sick as they may be contagious.
Do not get close to them and do not touch objects they have used,
like their utensils for instance.
•Clean your surroundings regularly, as well as the sanitary appliances
you use. For example, clean your counters and other surfaces that
you touch often with your hands. Also wash toilets and sinks in order
to keep them clean. Cleaning is very effective in killing viruses, which
can survive on hard surfaces.
•Clean with soap and water or use domestic detergents.
•Vaccination is the best way to protect yourself and others. When
a vaccine against an infection or a disease is available, get it.
Control of the diseases
Immunoprophylaxis
Immunoprophylaxis against viral illnesses includes the use of vaccines or
antibody-containing preparations to provide immune protection against a
specific disease.
Active Prophylaxis (Vaccines)
Active immunization involves administering a virus preparation that stimulates
the body's immune system to produce its own specific immunity.
Immune Response to Vaccines: Vaccination evokes an antibody response and
stimulates T lymphocytes. Vaccine effectiveness is assessed in terms of
percentage of recipients protected and the duration and degree of protection.
Most effective viral vaccines protect more than 90 percent of recipients and
produce fairly durable immunity.
Passive Prophylaxis
Passive immunity is conferred by administering antibodies formed in another host.
Human immunoglobulins remain a mainstay of passive prophylaxis (and occasionally
therapy) for viral illnesses; they are usually used to protect individuals who have been
exposed to a disease and cannot be protected by vaccination.
THE END