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What Is A Virus

Viruses are microscopic organisms; arguably the very smallest of all living organisms. They are “pared down” to the most minimal components: genetic material and a container for the genetic material. The genetic material is a strand of DNA (or RNA). The “container” is known as an “envelope”. What they lack in size and physical complexity, they make up for in the amazing variability of illness which they cause.

When viruses infect a human they enter the cells of the body and use the cell’s energy and building blocks to manufacture more viruses. They are able to “commandeer” the human cell by going to the cell’s command center, the “nucleus”. There the virus inserts its own genetic material into the cell’s DNA.

There are many viruses which cause no illness to humans, however, little scientific attention is focused on them. Viruses which are “pathogenic” (harmful to humans) may cause disease in a number of ways. The viral infection may directly damage the host cell, the host’s immune system may harm the host cells in the process of trying to kill the virus, and finally the insertion of the viruses’ genetic material into the host DNA may cause problems such as cancer.

It should be noted that viruses have no “desire” to harm humans. Their only “desire” is to replicate (term for viral reproduction) and spread to other hosts. Replication occurs best in a healthy host, although a little diarrhea or “runny nose” and cough goes a long way in helping the virus spread to another host. Any virus which instantly killed its host would also die with the host. Thus, it makes sense that most viral illnesses result in self limited illnesses often with cough, sneeze, or diarrhea to ensure spread to other humans.

Medical science has expanded its war against viral illness, both in the form of immunizations and antiviral “chemotherapy” (“antibiotics” against viruses). However, because of serious side effects, the use of these medications or vaccines is not always indicated.

Viruses for which specific anti-viral medications exist

  • Cytomegalovirus
  • Human Immunodeficiency Virus (HIV)
  • Herpes Simplex Virus
  • Influenza A
  • Respiratory Syncytial Virus
  • Varicella Zoster Virus

Viruses for which active or passive immunization exists

  • Hepatitis A Virus
  • Hepatitis B Virus
  • Influenza A and B
  • Japanese Encephalitis Virus
  • Measles Virus
  • Mumps Virus
  • Polio Virus
  • Rabies Virus
  • Respiratory Syncytial Virus
  • Rotavirus (currently withdrawn)
  • Rubella virus
  • Varicella Zoster Virus
  • Yellow Fever Virus

*Additionally pooled immunoglobulins are occasionally used for a few other viral illnesses.

Viruses for which “non-virus specific” anti-viral therapies exist

  • Hepatitis C (interferon)
  • Measles (Vitamin A)
  • Papilloma virus (cimetidine-controversial)
  • Rhinovirus (zinc, Vitamin C-controversial)

The doctor said it was “probably just a virus”…

Viruses are often blamed for non-descript illnesses which result in nausea, fatigue, dizziness, and malaise (generalized “ill feeling”) and other symptoms. Viruses are known to have huge variability in the symptoms which they can cause. Few tests exist to confirm most viral illnesses and even fewer treatments for these viruses exist. When symptoms do not seem to fit with any specific illness, viruses are often to blame, and the infected child often recovers over the course of a week or so.

However a number of less common illnesses, and potentially serious illnesses may also present with similar symptoms. If your child is not improving, you should return to see the doctor.