quarta-feira, 28 de abril de 2010

Malaria - Chemoprophylaxis and Prevention Measures .*

Malaria - Chemoprophylaxis and Prevention Measures .*

* Prohibited the reproduction of this article without permission of the author

Dr. Wanir Jose Barroso
Hygienist, expert in epidemiology and control of endemic diseases by Fiocruz / RJ.
E-mail: wanirbarroso@gmail.com

Chemoprophylaxis for malaria should be used only in very specific situations and prescribed by doctors or specialist familiar with the advice to travelers.

Chemoprophylaxis in malaria is nothing more than the use of antimalarial drugs for malaria that does not twitch and we do not know whether or not we contract it. It is as if we tried to "prevent" the disease or lessen its symptoms, even without having it taken out, using drugs that are prescribed in their treatment and healing, believing that by doing so we would not have the disease or not would develop severe forms if we bitten by infected mosquitoes. These antimalarial drugs used in sub-therapeutic doses, such doses should be chemoprophylactic have only the function of eliminating a number of protozoa (Plasmodium) when they are already in the blood of patients infected with Plasmodium. Thus, the onset of symptoms may or may not be delayed if the Plasmodium or is not sensitive to the drug used.

The antimalarial drugs are specific only to cure malaria in therapeutic doses and not all antimalarials should serve or be used as chemoprophylactic. Each of these medicines has its own peculiarities: some are more toxic, others are daily or weekly, others are slow elimination process, others may develop severe side effects and others may not even offer any protective effect, and for all antimalarial used in chemoprophylaxis, these individually and using sub-therapeutic doses recommended for chemoprophylaxis fail to cure patients who contracted the disease, apart from very few exceptions.

Further, malaria chemoprophylaxis does not prevent malaria infection, ie, does not prevent the entry and multiplication of the parasite in the body are bitten by infected mosquitoes, and also has healing purposes, because the doses used in prophylaxis are less than therapeutic doses used in conventional treatment. Medicines are not vaccines. Antimalarial drugs or do not heal or cure the disease and when misused can cause resistance in the parasite, resulting in treatment failure. Those who make use of chemoprophylactic and are bitten by mosquitoes infected with Plasmodium, malaria has at least until the stage liver disease and develop if the disease proves resistant Plasmodium drug used.

Antimalarial chemoprophylaxis should be considered when the clinical conditions of travel and time spent in areas of known disease transmission. Chemoprophylaxis should only be used for those going to an area of transmission of P. falciparum where there is no medical help nearby, and tolerate the side effects of medication and will stay there at least for a period exceeding 12 days, which corresponds to an average incubation period of malaria by P. falciparum. Unfortunately only a few studies on the adverse effects caused by the continued use of these drugs.

The antimalarial drugs used as chemoprophylactic have several contraindications. Special attention should be given to pregnant women, newborns, elderly, metabolic and infectious diseases, people with cardiac and neurological problems, and also for people who have to be under constant vigil, like airplane pilots. Among the undesirable side effects reported in this group of drugs that have varying degrees of toxicity are: drowsiness, nausea, diarrhea, bitter mouth, blurred vision, tinnitus, tremor, cardiotoxicity, and intolerance among the most serious seizures.

Malaria drug use chemoprophylactic may delay the onset of symptoms, extending the incubation period and sometimes do not result in any protective effect if the circulating Plasmodium is resistant to the drug that is being used. Several strains of P. already have proven resistant falciparum front of several antimalarial drugs in many endemic regions. Chloroquine, for example, no longer be used as chemoprophylaxis whereas P. falciparum shows already resistant to it in about at least 90% of the endemic areas of the planet.

The diagnosis and treatment in the initial phase of the disease have similar goals to that chemoprophylaxis is to prevent the development of severe forms, whose main cause is the delay of diagnosis and treatment.

He who knows the symptoms and be with suspected malaria to have frequented areas of disease transmission and goes in search of medical help to diagnose and start treatment, you always have a better prognosis than the one that makes use of chemoprophylactic. The indiscriminate use and the use of sub-therapeutic doses of antimalarial drugs are factors of chemoresistance of Plasmodium, as with bacteria to antibiotics.

Another important negative factor that must always be considered is that these schemes used in chemoprophylaxis cause a false sense of security, including making the traveler more to expose the bite of mosquitoes, making it more vulnerable to contracting the disease, besides having to adhere to the discomfort of using daily or weekly depending on the drug used. Chemoprophylaxis should not have their purposes "protective" confused with a vaccine. Although it is making use of chemoprophylaxis, can develop the disease and its severe forms are bitten by infected mosquitoes. Malaria unfortunately, there is still no specific and effective vaccine available.

Antimalarial chemoprophylaxis in the protection levels offered are dependent on many factors, such as using regular doses of the drug, the fact of Plasmodium not be resistant to the drug prescribed and the patient to metabolize, eliminate, and tolerate the drug well and not develop undesirable side effects .

Antimalarial chemoprophylaxis, if indicated, should be made strictly within the medical advice received, that is, one should never replace the product, the duration or the dosage provided by the physician who prescribed.

In summary, the best prevention against malaria remains:
1 • Whether or not you are in an area of malaria transmission, or if there are people contracting the disease in the region where it is;
2 • Avoid mosquitoes in areas of transmission with the use of repellents, insecticides, screens on doors and windows, mosquito nets or do not attend flooded areas where there are natural breeding sites;
• Know the three main symptoms of the disease (fever, body aches, vomiting, diarrhea, abdominal pain, loss of appetite, dizziness, feeling tired and others);
4 • Thinking of malaria is fever associated with other symptoms suggestive of having visited areas of disease transmission;
5. Know where to get medical help or information for the diagnosis and treatment both in and outside the endemic area;
6 • And do not self-medicate;

Find and forward in areas of malaria transmission febrile patients for diagnosis and treatment is the primary measure to contain outbreaks or epidemics, preventing the disease from spreading or take epidemic proportions. While there is a sick and without treatment in these regions there is the possibility of other people also contract. The groups most vulnerable to develop severe forms of the disease are children, elderly, people who contract the disease for the first time, pregnant women and patients with other infectious diseases.
Malaria in any region of the planet remains a parasitic disease of the most serious of rapidly evolving, but curable condition that is diagnosed and treated as rapidly as the disease requires. The disease can seriously compromise the functioning of various organs like the liver, kidneys, spleen, lungs and brain as well as evolve to severe forms with malaria coma and even death in a few days if there is delay in diagnosis and treatment. Death from malaria is caused the failure of these organs.
Malaria, mainly caused by P. falciparum, should always be considered a medical emergency!

Um comentário:

Isabela disse...

Olá Wanir!

Finalmente, estou comentando no seu blog!!! =)

Parabéns pelo trabalho!