Tuberculosis (TB) is an infectious disease attributable to bacterial invasion that is often acquired during childhood through inhaling the bacterium called tuberculosis bacilli (an elongated, tubular bacterium) transmitted by means of the cough or spray due to sneezing by an individual who is already infected actively. Tuberculosis begins in the lungs and may take one of the forms - primary infection (initial infectivity) or reactive infection. The immune system of our body is able to make the tuberculosis bacilli inactive in about 90% to 95% cases of primary infection. However, the bacterium stays alive and may possibly spread through the lymphatic system as well as the blood circulation all over the body.
Apart from the development of scars as well as swelling and tenderness of the lungs, the only other indication of infection by tuberculosis bacilli is a reaction to tuberculin injection - which is basically the bacterium's sterile extraction. When this substance is administered in the form of an injection into the patient's skin, reaction is noticed only in individuals who have been infected by the bacterium earlier. Subsequently, preventive measures are adopted.
The second form of the disease, called reactivation tuberculosis (wherein the devastating and progressive disease emerges gradually and occasionally even proves to be fatal in adults) develops only in about 5% to 10% of people who already have a primary infection when the natural defenses of their body diminish. An individual may develop reinfection tuberculosis, a form of the disease that is identical to reactivation tuberculosis clinically, when he/ she already has a dormant primary infection and is infected again.
The symptoms associated with reactivation tuberculosis (also called reinfection tuberculosis) are likely to be misleading, because this form of TB may begin in any body part that has already been infected by bacilli. In most cases, the disease first appears in the lungs' upper lobe and is generally diagnosed following an X-ray of the area. The initial signs, which usually emerge gradually comprise overall poor health; losing weight and appetite; cough and fever. This form of tuberculosis generally happens in adults, usually in people who are aged above 70 years.
Anti-tuberculous medications work in two ways - by killing the bacterium right away or by restricting the bacterium from propagating. While these medications begin combating the bacterium within a few days of starting treatment, it may take a few weeks' time to notice the advantages of undergoing the treatment. Since the infection is eliminated slowly, it allows the healing processes of the body to mend the harms caused by the ailment. As the medications start taking effect, it results in the gradual subsidence of the symptoms like cough and fever. At the same time, the patient gains normal weight, regains appetite and the general health is also restored.
Use of a number of anti-tuberculous medicaments may possibly result in unpleasant side effects like vomiting, nausea and pain in the abdominal region. At times, they may even cause severe allergic reactions. These adverse reactions usually take place during the treatment's second month and are likely to be similar to the symptoms associated with the disease, such as fever and a general feeling of being unwell. When such adverse reactions occur, it necessitates the current anti-tuberculous medication being substituted by a different one.
A number of anti-tuberculous drugs, such as isoniazid and rifampin, may have a negative effect on the functioning of the liver. In addition, isoniazid may also result in a deficit of the vitamin called pyridoxine. However, physicians may prescribe this vitamin along with isoniazid. On the other hand, using the medication ethambutol may possibly result in changes in your eye sight and this is why physicians avoid prescribing this medication for small children as they are not able to notify about the forewarning signs.
Since the development of the unpleasant side effects of using anti-tuberculous medications is generally associated with the medications' level in blood circulation, it is important to monitor the doses carefully. Additional care should be taken for children, aged people as well as people whose kidney functioning is below normal.
Compared to bacteria, viruses are very simple and quite small microorganisms that have less aptitude to sustain themselves. It is only possible for viruses to live and proliferate when they enter the cells of another animal's body. Since viruses are able to carry out very less functions on their own, it has been very difficult to develop medications that interfere with or ends their life cycle without causing any harm to the human cells.
Several dissimilar types of viruses exist and infections caused by them result in ailments that vary widely vis-à-vis symptoms as well as seriousness. The most common viral ailments are cold, flu and illnesses that are similar to influenza, in addition to diseases that occur during childhood, for instance, chicken pox and mumps. Infections of the throat, bronchitis, gastroenteritis, pneumonia and meningitis are usually, but not all the times, attributable to viruses.
We are fortunate that normally the natural immunity of our body is sufficiently strong to prevail over most such infections, together with medications that are prescribed to alleviate pain and cure fever. Nevertheless, some viral diseases are more severe in nature, such as meningitis and pneumonia need close medical monitoring.
Viral infections cause another major problem - that is their rapid pace of proliferation. Immediately after the appearance of the symptoms of the disease, the viruses responsible for it grow in such large numbers that most medications are likely to have very little impact. Therefore, it becomes necessary to give anti-viral medications during the course of treating the infections. Alternatively, antiviral agents may also be used in the form of a preventive measure. It is possible to prevent a number of viral infections by giving vaccinations.
Of late, scientists have developed some medications that are useful in treating infections caused by specific viruses. There are several anti-viral medications, for instance, acyclovir, trifluridine, idoxuridine and vidarabine, that work to put off the development of the genetic materials of viruses. In other words, these medications impede the replication of viral DNA, making it impossible for the virus to propagate. By putting an end to the multiplication of the viruses, these medications help in preventing their spread to plague the healthy cells and, at the same time, improve the symptoms caused by infections. However, these medications are not so effective in the case of herpes infections, because they are not able to completely eliminate the virus from our body. Hence, the infections may flare up some time later on.
The anti-viral medication amantadine works quite early in the life cycle of influenza virus and helps to check it from propagating. The effect of this medication is the utmost when it is employed as a preventive measure, given right at the onset of the infection.
However, anti-viral medications that are used topically do not start working right away, but if treatment with these medications is started just when the infection occurs, application of these medications may be helpful in terminating a herpes outbreak. In this case it normally takes about two to three days for the symptoms to disappear. You should know that using anti-viral ointments may result in flushing and irritation. Anti-viral medications may be given orally or administered in the form of an injection and their use result in queasiness and light-headedness.
As a number of anti-viral medications are emitted through the kidneys, it is essential to prescribe them very cautiously for people whose kidney does not function as usual. At the same time, use of a number of anti-viral agents may possibly have an adverse impact on the normal actions of the body cells, especially the cells present in the bone marrow. This is the reason why the anti-viral medication idoxuridine is only available for topical use.
Several contagious diseases, counting nearly all the familiar viral infections, only occur once in an individual's life. This is primarily because the antibodies that are produced in reaction to these diseases remain in our body afterward and they are ready to fend off any later invasion the moment the first contagious germs emerge. While the period and extent of this type of immunity may vary, usually it can keep on for an individual's lifetime.
With the advancement of medical science, it is now possible to provide artificial protection from several types of infections by means of giving vaccines that have been derived from transformed variety of the microorganism that is responsible for the infection. Administration of these vaccines encourages the immune system exactly in the same manner as the actual infection, and endow with a long-term, active invulnerability. For every disease, a dissimilar vaccine is administered, as each form of microorganism encourages specific antibody production.
Passive immunization is a different kind of vaccination that involves introducing antibodies from a person who has already recuperated from a specific contagious ailment. The antibodies are transferred using serum (a portion of our blood) that contains the antibodies.
Vaccines invigorate the immune system to produce antibodies that assist the body to defend itself from particular contagious diseases. Several vaccines are prepared using weakened pathogens (disease-bearing microbes) artificially and are known as live vaccines. Nevertheless, these enfeebled germs are also effective in promoting adequate antibody growth. There are some other vaccines that depend on killed (or inactive) pathogens or dormant derivatives. Though they are inactive or dead, they have the same effect on our immune system. This results in the development of useful antibodies; and a dynamic immunity is created.
Different vaccines provide different levels of protection against infections by microbes. While some of them give dependable immunity throughout our life, there are other vaccines that do not provide complete protection against any infection, and they may also be effective for just six months. It is possible to develop unpleasant side effects after being vaccinated, but these adverse effects are generally mild in nature and also disappear soon. The most common side effects of vaccination may include reddening and a somewhat raised painful spot at the site of inoculation. In addition, people who have been vaccinated may develop mild fever or ailments similar to influenza, which remain for a couple of days.
In the case of most children, the immunity provided by vaccine by far outweighs the serious reactions it might cause. While there have been some reports as well as concern regarding the probable relation between lasting neurologic problem and vaccination against whooping cough (pertussis), there is no evidence to substantiate such apprehensions scientifically. While it is possible that receiving the pertussis vaccination (which is usually administered along with vaccines against tetanus and diphtheria and the combined form is known as DTP) may result in minor convulsions; this side effect, accompanied by fever, only lasts for a brief period and disappears without any treatment.
It has been found that children who have endured such convulsions recuperate fully and do not suffer from a neurologic disorders or problems related to their development. In addition, it is possible to lessen the chances of developing high fever after being vaccinated with DTP by giving the children acetaminophen when they are being vaccinated. Children who develop infections that are further serious compared to ordinary cold are not given routine vaccinations till they recover completely.
Here is a word of caution. Pregnant women should never be given live vaccines, because they may possible harm the fetus. People, who have debilitated immune system owing to any ailment or treatment with any medicine, should also not receive live vaccines. Moreover, people taking corticosteroids should also postpone receiving live vaccinations till they have completed their therapy with the medication.