LEARNING ABOUT VIRUSES

VIRUS OVERVIEW AND UPDATE

 

Severe Acute Respiratory Syndrome (SARS)

There is a new strain of the potentially deadly virus related to SARS. The initial fear was we’d be facing an aggressive form like the outbreak in China that killed one in ten victims and infected about 8,000. The World Health Organization reports this new form is not as easily spread from person to person. Like the SARS outbreak which began in China in 2002, it is related to a common cold virus of the coronavirus family. Only one person has died. One person is critically ill. Both are from the Middle East where this new form was first identified.

Influenza A (H3N2v) Variant Virus Outbreaks

The H1N1 virus, found in pigs (2010) and humans (2011) has now surface as a new variant which has infected humans resulting in one death. The variant is transmitted from pigs to humans by droplet contact. Most infected developed only mild symptoms. Any one who is under age 5, over 65, or are pregnant, have diabetes, heart disease or weakened immune systems are at high risk of serious complications. They must have no contact with pigs. There is no risk with eating cooked pork. The seasonal flu vaccine will not protect you from this disease. See a doctor early if you suspect this infection as antiviral drugs may help.  http://www.cdc.gov/flu/swineflu/h3n2v-outbreak.htm

Viruses in Health and Disease

We have all had numerous viral illnesses with little evidence of persistence. Yet, after mapping the human genome, scientists found viruses incorporated into human genes. In fact, 8% of the human genome consists of endogenous (embedded segments) of virus sequences we pass on to our offspring. Many of these are retroviruses, based on RNA. To be functional, RNA viruses must insert themselves into a DNA-based genome which contains reverse transcriptase. The enzyme allows the RNA virus to reproduce itself using the cell’s machinery.

We have known for years that cancers arise from viruses. The Human T-cell Lymphotropic Virus (HTLV) was the first human retrovirus discovered. This virus affects T lymphocytes, white cells responsible for fighting infection. HTLV-1 and HTLV-2 are involved in numerous disease processes including leukemia, lymphoma, skin and neurologic disorders.

The Human Papilloma Virus (HPV) causes a variety of aggressive cancers: cervical, penile, oral and throat. Prevention of HPV-based cancers is now possible with an immunization. (HPV Vaccination) For guidelines: www.cdc.gov/vaccines/vpd-vac/hpv/

 

A recent discovery by researchers at the University of Texas broadens understanding of the viruses embedded in our genes. They found human genomes and those of other mammals contain Bornavirus DNA. This is an RNA virus which activates viral factories within the cell nucleus establishing persistent infection, and has been passed in mammals throughout evolution. Researchers looked at more than 200 genomes and found Bornavirus sequences in them. Why do you care?

First of all, Bornavirus infects a large number of animals internationally from birds to primates. It causes a severe and usually fatal form of encephalitis with striking behavior changes in horses, but is also seen in cattle, sheep, cats and canines. Changes in horses include: staggering, agitation and depressed behavior. Transmitted by contact with secretions, there is an incubation period from weeks to months.

Viral infections caused by influenza, cytomegalovirus (CMV) and herpes simplex virus (HSV) may be involved with psychiatric disorders but no clear causation has been reported. Bornavirus antibodies and viral RNA have been found in humans with psychiatric disorders but there is no proven direct causal link between Bornavirus infection and mental problems. Genetic and environmental factors both interact in the expression of psychiatric illness including schizophrenia and mood disorders. Research is ongoing and is a field to watch.

Information on this virus, its diagnosis and correlation with evidence for possible infection in humans causing mental disorders is discussed in detail in the following source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC164222/ from Clinical Microbiology Reviews.

There is much we do not know about how latent viruses may affect our health. Maybe they will never surface and will lie dormant in our genes over a lifetime. Many people are all too aware of Varicella Zoster Virus. This one lies dormant after having chicken pox as a child. Anyone who has had chicken pox and recovered may develop this painful blistering skin rash that follows nerves along one side of the body. One out of three people develop shingles. The best treatment is prevention and an immunization is available, even at local pharmacies. There are medications that help and you should see a doctor if you develop shingles. Zostavax® immunization is recommended by the CDC for those over age 60.  Guidelines at the CDC:

http://www.cdc.gov/vaccines/vpd-vac/shingles/vacc-need-know.htm#get-vaccine

Studies show viruses change the way genes turn on and off in embryonic stem cells. As more research information surfaces, studies using new molecular mechanisms to turn cell functions on and off are designed. Cancer treatment studies are now targeting the on-off switches which could stop rapid growth of abnormal cells and halt cancer growth.

Betty Kuffel, MD

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BEAT THE FLU SEASON: IMMUNIZE NOW

Prevent Influenza: B and A including H1N1, H3N2

Influenza is always around, but the typical “flu season” in the US extends from October to May. It takes about two weeks for your body to generate antibodies against the flu following an immunization, so now is the time to immunize yourself and your family. Vaccines are available at many convenient locations, even in pharmacies, so there are no long lines.

We may have forgotten the scare and severity of the H1N1 (swine) flu illness in the past, but recent illnesses and a death from swine flu contracted by people attending fairs and touching pigs has brought the disease back into focus. Treatment may not be effective, so it is best to avoid the disease altogether. You can do that by arming yourself against the H1N1 viral illness and other seasonal flu types by an immunization which covers a variety of influenza strains.

An annual immunization is recommended because flu viruses change. The vaccine is re-formulated based on the observed changes. Just because you had the “flu” once, doesn’t mean you are immune. Natural immune responses decline over time. The inclusion of a viral strain in the vaccine is based on research and anticipated spread of illness type. This year the vaccine protects against three different flu types: influenza A (H3N2 virus, influenza A (H1N1) and influenza B viruses.

You have a number of immunization options:

“Flu shot”-an inactivated vaccine containing a killed virus is given with a needle and is for healthy adults, children older than 6 months and for people with chronic medical conditions

  • Regular: 6 months and older
  • HD (high dose): for people age 65 and older
  • Intradermal: for ages 18-64

Nasal-Spray: Made from weakened viruses which do not cause the flu. Approved for healthy people ages 2-49 that are not pregnant.

At the website listed below there are immunization guidelines. People who have severe egg allergies and anyone who has had a severe reaction to the vaccine in the past should not be re-immunized. Others who are ill and feverish, and those who have had a paralytic illness called GBS (Guillain-Barré Syndrome) should discuss the situation with a physician. Children younger than 6 months of age are not approved for flu immunization.

General immunization recommendations include: People with lung conditions such as asthma and COPD; Diabetics and people 65 years and older; Pregnant women; Those associated with the above examples including caregivers and household contacts.

If you develop influenza, what are the symptoms?

  • Sudden onset of a high fever
  • Headache, cough, sore throat, runny nose, aches and tiredness
  • Diarrhea and vomiting can occur but are less common and more often in children

What to do: Although the above symptoms might be flu, other illnesses have similar symptoms. If you are concerned, especially if you have asthma, diabetes, chronic lung disease or have been diagnosed with congestive heart failure, you should discuss your symptoms with your doctor. There are some medications that help, in fact, some specifically treat viral infections. These antiviral drugs may make you feel better faster and help prevent complications, but must be started within two days to have benefit.

There are actions to decrease your risk of infection, such as:

  • Avoid people who are coughing or other flu symptoms
  • Be sure to wash your hands
  • Don’t shake hands with people
  • Use alcohol based wipes or sanitizer solutions frequently

It takes about two weeks for your body to produce antibody protection after you receive the vaccine. The best protection is to GET YOUR IMMUNIZATION NOW!

You have two options:

  • The shot—when this vaccine containing a killed virus is injected, your body begins building antibodies against the illness. Generally healthy people, those with chronic disease and children over 6 months of age are approved for this method
  • The nasal spray—this vaccine is made from live but weakened viruses that do not cause the flu. The body senses it’s presence on the nasal mucus membrane and mounts an antibody response. This is approved for healthy people between the ages of 2-49. It is not used in pregnant women.

NOTE: You cannot get influenza from the vaccine. But vaccine effectiveness varies and flu viruses are constantly changing.

Possible Side effects: Soreness, redness and swelling at the site of the injection, low grade fever and aches, runny nose, wheezing, headache, vomiting, muscle aches, fever, sore throat, cough.

For more information: www.cdc.gov/flu/protect/keyfacts.htm and Influenza Vaccine Safety at the same site.

For questions related to your personal health issues, consult your physician.

Betty Kuffel, MD