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12.3.3. Prevention and cure of infectious diseases

Prevention and cure of infectious diseases

To avoid contracting infectious diseases, although our immune system is very effective, we must follow some basic rules to avoid them.

  • Good personal hygiene is essential. Washing your hands before eating or handling food, after going to the bathroom, after covering your mouth when sneezing or coughing, etc., reduces the risk of contagion of diseases .
  • Food must follow food hygiene that guarantees its good condition and avoid food poisoning.
  • It is also important that the environment in which we live is also in hygienic environmental conditions.
  • Using condoms during sexual intercourse also prevents the spread of sexually transmitted diseases.
  • If we have animals at home, they have to be well cared for and vaccinated to avoid the transmission of diseases.
  • There are vaccines against some diseases that prevent us from getting sick even when we are exposed to them.

Some important concepts about preventing and curing infectious diseases are as follows :


The vaccine is a preventive method (not curative) which consists in introducing into the organism bacteria or killed viruses or attenuated that fail to cause disease, but able to trigger a specific immune response. Lymphocytes recognize these antigens and make antibodies and memory lymphocytes. If later, the vaccinated person comes into contact with that pathogenic microorganisms, they will not suffer the disease, since they have specific immunity for that antigen.

This type of immunity is called active artificial immunity. The lymphocytes that have learned to manufacture an antibody will not forget how they occur, and act quickly if necessary.

The vaccines possible to prevent many diseases such as smallpox, which was eradicated from Earth in 1980. For other diseases is more complicated and is still being investigated. In addition, some microorganisms, such as the influenza virus, have changes in their antigens every year, so that the body does not have the antibodies prepared for them, so you can get the disease.


By U.S. Navy photo by Mass Communication Specialist Seaman Apprentice Robert Winn [Public domain], via Wikimedia Commons

Serum therapy

The serum therapy is a (non - preemptive) therapeutical method used when the person is already ill, and it is too late to prevent the disease with vaccinationIn this case, antibodies from the blood of another person who has suffered and overcome the disease are introduced into the sick person. This fluid with antibodies is called serum, and it will allow you to fight the disease with the antibodies that have been injected into you.

This type of immunity is called passive artificial immunity, since the patient does not make the antibodies himself, and when they disappear, the person is no longer immune to that disease.

Activity: Either serum or vaccine.

Curiosity: How the nurse who was infected with Ebola was cured.

Answer in your notebook

12.7.- What is the difference between vaccination and fluid therapy?


The antibiotics are chemical substances produced by a living being (fungi and bacteria) or synthetic derivative that prevent the growth of bacteria pathogenic. The first antibiotic was discovered by Alexander Fleming in 1928 and was called penicillin.

Although the use of antibiotics saves many lives, caution must be exercised in their use:

  • You only have to use them when the doctor prescribes them, since if we abuse their consumption, the microbes become resistant and lose their usefulness. In addition, we also have symbiotic bacteria in our body that are necessary and that can die with this antibiotic.
  • Antibiotics only kill bacteria, so they won't do anything against viruses (they're not living things), so I shouldn't use them if my illness is caused by a viral infection.

If the infection is caused by viruses, the appropriate treatment is the use of antivirals. If it is caused by fungiantifungals or antifungals. If the infection is by protozoa, it is difficult to treat due to its great variety.

Answer in your notebook

12.8.- Can illnesses like colds or flu be fought with antibiotics? Reason for the answer.


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