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Definition

Bacteria are the oldest and most abundant organisms on Earth. Bacterial cells are smaller than the human red blood cell. Unlike human and animal cells, they lack a nucleus. Like plant cells, bacteria are surrounded by a carbohydrate cell wall. Bacterial species are responsible for many of the world's infectious diseases. Unlike viruses, which also cause infections, bacterial infections can be treated more effectively with antibiotics that kill them or disable growth or reproduction.

Bacteria are both helpful hosts and harmful sources of disease. In the large intestine, native bacteria aid in digestion and prevent the build-up of other toxic bacterial species.

 

What  Are  Bacteria?  

You would be amazed at the hosts of critters out there waiting to take up residence in your body. There's everything from tapeworms that are yards long to tiny protein fragments (prions) that can multiply in your brain and give you Creutzfeldt-Jakob disease, the human version of mad cow disease. They're all lurking just out of reach of your senses. We will discuss here only one category of germs - bacteria.

Known to scientists as procaryotes, bacteria are the largest class of creatures on earth, even larger than beetles. They are very simple organisms -- single cells with no nucleus. Nevertheless, they eat, are capable of reproducing themselves, and have a membrane or shell that separates their insides from the outside world.

Bacteria, the most familiar of infecting agents, cause 90 percent of hospitalized infections in developing countries, although they contend with viruses for being the most diversified. Bacteria cause most of the serious, acute infections we get and are the first group of germs to yield to chemical cures, which is to say, antibiotics. From bacteria we get urinary and kidney infections, strep throats, pink eye, boils, typhoid, cholera, tetanus, gangrene, diphtheria, whooping cough, anthrax, Lyme disease and most of the serious cases of dysentery, meningitis and pneumonia. But they can't take credit for viral hepatitis, colds, influenza, rabies, AIDS, giardiasis, malaria, worms, athlete's foot, hantavirus, kuru, bovine spongiform encephalopathy, lymphocytic choriomeningitis, Ebola virus or bread mold. Because it is so important, we'll also call tuberculosis (TB) a bacterium, even if that classification is not quite accurate.

For the most part, bacteria are the smallest free-living organisms in nature, having all the genetic material necessary to live independently. This is not to say that many of them don't enjoy the parasitic life, but as a class they are complete life forms unto themselves. Smaller living organisms such as viruses are obligate parasites, unable to survive outside another living system, such as yours, for example.

How bad are bacteria?

Bacterial infections fill the space between pimples and plague. Recently doctors have discovered bacterial infections can even cause stomach ulcers. They also cause toxic shock syndrome and the recently publicized E. coli infections children get from contaminated public swimming pools or hamburger meat. Bacteria are responsible for the bubonic plagues that ravaged Europe throughout much of the last two millennia.

Since Alexander Fleming discovered penicillin in 1928, bacteria have encountered a new enemy, and have responded very ingeniously. Within 50 years, nearly all disease-causing bacteria have developed resistance to at least one antibiotic. They have even learned how to pass their resistance on to their relatives. But the most frightening news is that some bacteria have developed resistance to EVERY known antibiotic. Much of this resistance has come from improper use of antibiotics, which is the main reason you will never be able to buy them over the counter, at least in this country. Incomplete doses kill all but the hardiest germs, which are then able to develop even stronger resistance through mutation and "natural selection." The lessons here are "Finish your prescription. Kill them all, or they'll come back to get you, and don't take antibiotics for illnesses caused by viruses." Given the tens of millions of dollars and the years of processing required to get a single new drug on the market, bacteria have a clear advantage when it comes to efficiency.

TB is a classic example of selective development of resistance. It used to be universally susceptible to INH (isonicotinic acid hydrazide), a cheap, safe treatment that spread around the world. Inadequate dosing was the rule rather than the exception, especially since it takes months, rather than days, to eradicate TB in a patient. Now, TB can be resistant not only to INH, but also to many more expensive and more toxic drugs. Some TB strains are resistant to every drug. Now that AIDS has released TB from the constraints of our natural immunity, TB is increasing by as much as twenty-fold in African countries heavily stricken with AIDS. TB throughout history has been the number one killer.

TB isn't exactly a bacterium. TB is called a mycobacterium because it is very much like a bacterium, but "myco" because it has some properties that resemble the next higher category, fungi. Leprosy, now known as Hansen's disease, is also caused by a mycobacterium.

Is It an Allergy or Sinusitis?

 

Sinus infections may be on the rise in the United States, and many of them creep up on us as a cold or an allergy, a survey shows.

According to a survey of doctors and patients, 42 percent of those surveyed said they suffered through at least one sinus infection in the past 12 months, a jump of 9 percent from the previous year. And 39 percent of them said their sinusitis started with an allergy, while 28 percent said the infection began with a cold.

The survey also shows sinus problems wreak havoc with daily life. More than half of those questioned say they lost sleep at least twice during the allergy season last year, and 42 percent missed anywhere from one to seven or more days of work or school because of the nasty and bothersome infection.

Severe allergy season a factor

This year's unusually warm winter is not going to make it any easier on sinuses, according to the American Academy of Otolaryngology-Head and Neck Surgery.

"This year's warm temperate winter means we are going to see an earlier and more severe allergy season this spring. And with a more severe allergy season, we're going to see a jump in the number of sinus infections."

Blame swollen sinus passages caused by an allergy or a cold for sinusitis." Those warm, wet passages are a playground for bacteria. "An inflamed swollen sinus passage leads to blockage of the sinus opening and a backing up of nasal and sinus mucous."

Sinusitis is one of the most commonly reported diseases in the United States, affecting an estimated 37 million people and accounting for more than 11.5 million visits to the doctor each year.

How to tell if you have sinusitis

"The problem is, that most people can't tell the difference between allergies or a cold and sinusitis."

A couple variables differentiate allergies or colds from sinusitis. "People need to understand that a head cold and allergies can prime the sinuses, making them inviting to bacteria. Sinusitis generally lasts 10 to 28 days and usually follows a cold or allergies. So, if you've got pain in the forehead or the face, accompanied by coughing, fever and nasal congestion lasting more that two weeks, you need to go and see the doctor."

The second variable is the nature of the mucus that develops. "Allergies usually involve itching and clear, watery nasal discharge. But if you're getting excessive thick, sticky yellow-green mucous or mucous that tastes bad, you need to seek the advice of a doctor."

The cure for sinusitis?

"Antibiotics are the only things that work on bacterial sinusitis.

For More Information: Please  consult  your  attending  physician  on  your  next  visit.