Michael E. DeBakey VA Medical Center - Houston, Texas
ABC’s of Vaccines
September 2, 2011
The immune system is our body’s internal defense complex. It includes several types of white blood cells (WBCs). Our white blood cells fight germs. After having fought against some types of germs our white cells can remember the appearance of these germs. The WBCs can quickly identify and kill the germs if the germs attempt another invasion. This effective response is why certain germs, such as the measles virus, can only infect us once. But even one infection with such a dangerous germ can be dangerous, even deadly. Fortunately, scientists have developed ways of preparing our immune system for battle without our having to get sick in the first place. The process of building up our internal defense complex is called immunization. It is done by giving us vaccines.
There are three general types of vaccines:
• Killed vaccines
The production of killed vaccines involves the use of heat, radiation, or strong chemicals to kill certain germs. Some killed vaccines contain only a piece of the germ. An example of a killed vaccine is the pneumococcal vaccine, a vaccine that protects us against a type of bacterium that commonly causes pneumonia. Killed vaccines are very safe.
• Live vaccines
This type of vaccine is made from a germ that has been markedly weakened, but not killed. Live vaccines include the measles and mumps vaccines. These vaccines are very effective. However, because the germs are not dead, live vaccines are generally not given to people whose immune system is weak because of some type of serious underlying disease, such as AIDS.
• Toxoid vaccines
Some germs produce toxins, or poisons. Our immune system is able to able to neutralize these toxins. Toxoid vaccines help prepare our internal defense complex for this task. A prime example of a toxoid vaccine is the tetanus shot.
The development of vaccines has been one of the most important advances in medical science. We should not ignore the benefits of these potentially life-saving immunizations. That is the truth about our health.
Influenza is a dangerous infection that is caused by a group of viruses. Exactly which strain (or strains) of these viruses is apt to sweep across the globe each year is generally predictable. The flu season in the United States generally starts around September or October and ends in the spring. The exact reason these viruses tend to attack us during these months is not entirely clear. Fortunately, flu vaccines produced each year help our immune system prepare to battle this germ before it hits us. It is important to remember that flu shots are administered every year because the vaccine lasts only 6-12 months.
The flu vaccines are made from viruses that are grown in eggs. The process of growing viruses takes time and cannot be rushed. Therefore, scientists decide in the spring each year what strain (or strains) of the flu are most likely to sweep the country in the following fall or winter.
There are two types of influenza vaccines:
Flu shots - Killed influenza vaccines are given through injections. These shots are very safe. The flu shot is the type of flu vaccine that is recommended for pregnant women. The common side effect of the shot is some soreness around the injection site; this soreness usually lasts a day or two.
Nasal flu mist - The live virus influenza vaccine is administered via a mist that is sprayed into the nose. Although the weakened virus does not cause an actual flu infection, this vaccine can lead to some flu-like symptoms, such as muscle aches and a headache. The nasal flu vaccine is not recommended for children younger than two years of age, adults older than 49 years, pregnant women, or for people who have a serious underlying disease, especially one that may weaken their immune system.
Influenza is a dangerous disease. It kills about 36,000 people in the United States each year. Getting a flu vaccine reduces our chance of developing the flu – or at least lessening its symptoms – by as much as 90 percent. This is why nearly everyone should take the vaccine every fall.
Contributed by John F. Tompkins II, M.D, author of An Ounce of Prevention: The Truth About Our Health.
Visit Health Promotion/Disease Prevention webpage for more information on health and wellness.