Book: A Planet of Viruses by Carl Zimmer

This a little book of essays about viruses written "to help people understand more about viruses and virology research." There are 12 chapters and a lovely photo at the beginning of each chapter showing viral forms:

1. The Tobacco Mosaic Virus was discovered by Dutch scientists Mayer and Beierinck in the late 1900s by filtering diseased and ground-up tobacco plants through a fine filter that trapped plant cells and bacteria. The juice that got through the filter still infected plants. "Beijerinck could add alcohol to the filtered fluid and it would reman infective. Heating the fluid to near boiling did it no harm. Beijerinck soaked filter paper in the infectious sap and let it dry. Three months later, he could dip the paper in water and use the solution to sicken new plants." He first used the word virus "to describe the mysterious agent in his contagious living fluid."

2. The Uncommon Cold - Rhinovirus. A virus with only 10 genes and spread by contact. Wash YOUR hands and don't touch your face. Nothing much works to "cure" the common cold.....yet. Scientists are always working on vaccines.

3. Influenza virus. "In 1918, a particularly virulent outbreak of the flu killed an estimated 50,000,000 people. Nowadays, approximately 300,000 people die worldwide from the influenza virus. H1N1 is a flu virus that, fortunately, was not all that virulent. Wash your hands and don't touch your face. See Contagion (movie) if you want more information about how a flu pandemic could (and probaby will) eventually happen.

4. Human Papillomavirus (HPV). Can cause cervical cancer but there is a vaccine. "Of the 30,000,000 American women who carry HPV, only 13,000 a year develop cervical cancer."

5. Bacteriophages. A possible alternative to antibiotics, bacteriophages (phages) are viruses that attack bacteria, which is noteworthy as antibiotics continue to become resistant to the organisms they target.

6. Marine Phages. Interesting chapter about viruses living in the oceans. Among other facts is this one:"By one rough calculation, 10% of all the photosynthesis on Earth is carried out with virus genes" or "The genetic makeup of marine viruses...matches almost nothing...Only 10% showed any match to any gene from any microbe, animal, plant or other organism--even from any other known virus. The other 90% were entirely new to science." (This from seawater samples from Gulf of Mexico, Bermuda and the northern Pacific.)

7. Endogenous Retroviruses. Things get more complicated. I think these are viruses that acquire and add DNA from a host. It's all about exchanging DNA and mutating. "Each of us carries amost 100,000 fragments of endogenous retrovirus DNA in our genome, making up about 8% of our DNA."

8. HIV. Most likely spread from Kinshasha, and HIV probably came from chimpanzees. As our world becomes more a global community, viruses come along with us, moving more freely than ever, down rivers and roads and over the sea and land in airplanes, buses and trains. Do not have unprotected sex and wear gloves when encountering bodily fluids.

9. West Nile Virus. Spread by mosquitoes from infected birds to people. "Between 1999 and 2008, US doctors recorded nearly 30,000 cases of West NIle virus." One gets fevers, rashes and headaches but 85% infections do not even cause symptoms. Nevertheless, in those 10 years, 1131 people died, about 110 per year. There is no vaccine at this time. Warm, muggy, rainy weather are optimal conditions for mosquitoes and the time to be most cautious. Try not to get bit by mosquitoes.

10. Severe Acute Respiratory Syndrom (SARS) and Ebola or Predicting the Next Plague. SARS "started in Chinese bats....and began to spill over into a catlike mammal called a civet...and then evolved the ability to leap from human and human." The virus was discovered relatively quickly and measures were taken (quarantines, banning civets) and the virus "disappeared, but did cause 900 deaths.

Ebola virus, while horrific, "is just too good at making people sick and so it kills its victims faster than it can find new ones. Once an Ebola outbreak ends, the virus vanishes for years."

11. Smallpox. An interesting chapter on the history of a virus that "may have killed more people than any other disease on Earth." A vaccine was developed and smallpox was totally eradicated on Earth although there are small stocks here and there to be used by scientists (or bioterrorists). There is controversy about preserving this lethal virus of course.

12. Mimivirus, a gigantic virus with 1262 genes (usually viruses have about 10 genes) first found in a water cooling system. They are 100 times bigger than other viruses and are puzzling scientists once again on how and where to classify these organisms...where to place them on the life forms continuum.

So, very briefly, viruses are ubiquitous; minuscule (way smaller than bacteria) and are not killed by antibiotics. They have potential to kill us; they mutate; they move between humans and other fauna, changing as they go in order to stay alive.

Wash your hands; don't touch your face, and keep doing everything your can to promote your own personal healthy effective immune system.