Covid-19: why is there no specific remedy for viruses?

Much is known about diseases and medicines used to treat diseases caused by microorganisms such as bacteria – such as tuberculosis , cholera , syphilis , tetanus, etc.

However, when it comes to a viral infection (popularly known as viruses), the remedies in general do not have a specific targeting for the disease in question. But why this happen?

Better understand what a virus is and how the drugs used to treat conditions caused by them are studied – such as, for example, Covid-19:


what is a virus?

First of all, it is important to understand that viruses are not really considered living beings, since they do not have a cellular structure.

Thus, it is possible to define them as mandatory intracellular parasites . This means that they are beings totally dependent on other cells to reproduce and thus replicate themselves. That is, they have no metabolism independent of their host.

Regarding the structure, viruses are composed of a type of nucleic acid and a shell made of proteins (capsid) – this set is called a nucleocapsid.

It is worth noting that some viruses, especially those that infect animals, also have an external envelope called an envelope. This structure is derived from the cell membrane of the virus host.

So, basically, viruses are composed of the protein capsule that surrounds the genetic material – which can be DNA, RNA or both together, varying according to the type of virus.

It is also important to know that viruses can parasite all types of cells: prokaryotes (like archaea and bacteria) and eukaryotes (like fungi, microalgae, plants and animals).

What is the new coronavirus (SARS-CoV-2)?

The new coronavirus , which causes Covid-19, is just one type among existing coronaviruses. This family of viruses gets its name precisely because its envelope (external envelope), has S proteins – which have a stick shape and, with that, give the virus a crown aspect.

Because it is enveloped, that is, it has this external structure, preventive measures against coronavirus include practices such as washing hands with soap and using 70% alcohol. This is because this structure is composed of a layer of phospholipids (fat).

Thus, the action of agents such as soap and 70% alcohol, chemically, removes the envelope and denatures nucleic acids – which inactivates the action of the virus.

It is also worth noting that SARS-CoV-2 (a new coronavirus) invades the cells of the respiratory tract through the interaction of spine proteins (protein S) with a receptor for angiotensin 2 (ACE2) in human cells. Then, once inside the cell, it starts its replication process and, with that, causes the death of the infected cell.

What is the difference between viruses and bacteria?

Of course, there are many biological differences between viruses and bacteria. However, in general, there is a main factor that distinguishes viruses from other microorganisms: the fact that the others are beings with complete cellular structures.

As mentioned, viruses are not even considered to be living beings. They are more primitive and lack the structures that make cells work. In contrast, bacteria are single-celled (made up of a single cell), but your cell can function fully on its own.

In the case of viruses, to multiply, they need to invade other cells (of their host), guaranteeing their existence from another being.

Why are there no specific remedies to fight viruses?

Unlike bacteria, viruses do not have a complete cellular structure, which means that they need a host – in order to infiltrate your cell and thus act on the organism.

So, as bacteria have cellular structure, the drugs used to treat diseases caused by them ( antibiotics ) act directly on your cell wall. Thus, by identifying the bacteria, the drug is able to destroy it completely.

However, because viruses need other cells (from a host, like humans), it becomes more difficult to create a drug to fight them. For, to destroy this infectious microorganism it would be necessary to destroy the infected cell as well. Thus, the remedy is not only harmful to the virus, but it is also toxic to humans.

It is worth reinforcing, then, that the difficulty is basically reduced to the fact that it is very difficult to create a remedy that separates the virus from the infected cell. Because it is a process that, when carried out, needs to be done in an extremely meticulous way, with a lot of evaluation and study.

How are remedies against viruses studied?

For the treatment of new viruses (such as SARS-CoV-2), it is common for specialists to try to use existing drugs – created to treat other pathologies.

This testing is not done at random, but based on laboratory analysis. First, the action of some drugs is compared and, using analogy, the specialists select the remedies that appear to have the greatest potential to treat the new disease.

There are cases where the use of a single drug is not enough, it may be necessary to use cocktails (multiple medications), as in the case of HIV or Hepatitis C .

But it must be borne in mind that the tests are initially done in-vitro (in the laboratory) and that they will not necessarily show promising results when used in humans.

” alt=”” aria-hidden=”true” />

For this reason, the experiments start in the laboratory, then they are carried out on animals and, finally, on humans. When this occurs, the tests are first performed in smaller groups and, only if everything goes well, are they used in larger groups.

During this testing period, many drugs that have shown promise in the laboratory may turn out to be ineffective.

Therefore, it is possible to realize that this is a long process that involves a lot of trial and error, in addition to several studies and analyzes – until, finally, finding the best treatment for viral disease.

How is the treatment of viral diseases?

Considering the difficulty of creating specific medications for the treatment of diseases caused by viruses, in general, the treatment of these pathologies is aimed at the care of symptoms .

So the drugs are not used to eliminate the virus itself, but to relieve the symptoms that the viral infection has caused.

For example, when the body is suffering from an infection, it is common for the person to experience fever and bodily discomfort. In that case, analgesics and antipyretics may be indicated.

In addition, depending on the disease, basic care such as rest and hydration (drinking water) may be indicated.

It is worth mentioning that, in general, viral diseases can be prevented in a simple and practical way: hygiene care . This is because many diseases (colds, flu , diarrhea , etc.) can be transmitted through the hands, by touching contaminated surfaces, for example.

Thus, it is very easy for the hands to get the virus and, when touching the mucous membranes (mouth, nose and eyes), the person is infected.

Hand hygiene is already recognized worldwide as an effective measure for the prevention of viral infections. So, when you get home, after using toilets or before meals, this care is essential.

In that case, always choose soap and water. When it is not possible, 70% alcohol (liquid or gel) is also equally effective in this practice.

What medications are used for coronavirus?

Many scholars and experts around the world are looking for drugs to treat the new coronavirus. To date, some North American and Hong Kong researchers have identified approximately 30 drugs that may be effective against Covid-19.

Thus, these drugs become possible candidates to treat the new coronavirus. At the moment, three are undergoing clinical trials – among them is Remdesivir , which has been approved by the United States to be used in severe cases of the disease.

However, all we have so far are studies and research. There is nothing proven.

In Brazil, the Ministry of Health made available a document called “Guidelines for Diagnosis and Treatment of COVID-19”, in order to provide guidance to health professionals.

From the document, it is possible to find guidelines on experimental treatments that are in their initial stages and do not yet have greater evidence of efficacy – such as Tociliz u mabe , Ivermectin and Atazanavir .

There are also remedies that have been used in some patients but that also have no real proof of effectiveness. Understand better:

Hydroxychloroquine and Chloroquine

Chloroquine and Hydroxychloroquine are two different remedies, both used to treat Malaria and some autoimmune diseases – such as rheumatoid arthritis .

In general, these medications have a very similar indication. Its main difference is in the fact that Hydroxychloroquine is derived from Chloroquine and its action is less toxic to the organism.

In the case of Covid-19 treatment, the Ministry of Health reiterates that there is still not enough evidence to indicate these drugs in this case.

However, it indicates that Hydroxychloroquine and Chloroquine can be used in confirmed cases of Covid-19 and based on medical criteria. In these circumstances, use is recommended as an auxiliary therapy for critically ill and hospitalized patients.

This definition is based on clinical case studies carried out by national institutions.

From these analyzes, it was possible to verify that in some patients the use of Chloroquine (or Hydroxychloroquine) reduced the ability of the virus to release its genetic material inside the cells. Thus, avoiding the evolution of the disease to a more serious case.


Corticosteroid drugs (also known as corticosteroids or cortisone), are hormones with a potent anti-inflammatory action. Thus, they are often used to treat problems such as asthma , arthritis , lupus , etc.

As in all cases, self-medication with the use of corticosteroids is never recommended . In addition to the possible side effects and other dangers of self-medication, especially drugs in this class can cause problems such as cataracts or glaucoma .

” alt=”” aria-hidden=”true” />

As for the use of these medications during the treatment of Covid-19, the Ministry of Health indicates that there are controversies about using them or not.

This is because there are studies that indicate that the use of corticosteroids can cause an increase in viral load, length of hospital stay and risk of secondary infection. In contrast, other studies indicate benefits for specific subpopulations.

Thus, the Ministry of Health document states that the use of these drugs can be considered in the treatment of critically ill patients , with SARS (Severe Acute Respiratory Syndrome), who are hospitalized and within the context of clinical research.

Remembering that there is no evidence of efficacy and, by no means, self-medication is recommended – both with these and with other medications.

Antibiotic therapy

Antibiotics are used to treat diseases caused by bacteria, such as tuberculosis, tetanus, whooping cough , among others.

Therefore, they are not indicated for the treatment of viral infections, considering that their inappropriate use could even generate resistance in the body to these drugs.

In the case of Covid-19 treatment, the Ministry of Health reinforces about not using this type of medication inappropriately, in addition to the fact that there is no real positive evidence in the use of antibiotics against the new coronavirus.

However, in case the patient shows signs of bacterial infection associated with the Covid-19 case, there is an indication that the use of antibacterial drugs against acquired pneumonia can be considered in mild cases .

Among these remedies, the document mentions some such as Amoxicillin and Azithromycin .

In addition, it also reinforces that the evidence is limited regarding the use of Azithromycin with Chloroquine (or Hydroxychloroquine). Recalling the need to exercise caution in the use of this association – which can lead to an increased risk of cardiac complications.

Finally, it is important to reiterate that no type of self-medication is recommended and that there is (so far) no medication that has really proven effectiveness against the new coronavirus. All data obtained so far are based on studies.


The drug Remdesivir is an antiviral, initially tested (without success) during the Ebola epidemic between 2013 and 2016.

As mentioned, this medication is being analyzed by researchers and its use has been approved in the United States for patients in severe Covid-19 condition.

In Brazil, however, this remedy is not registered with ANVISA (National Health Surveillance Agency). In addition, the document published by the Ministry of Health mentions Remdesivir, reinforcing that the studies are preliminary and there is insufficient evidence to approve their use at the moment.

In general, studies that showed the effectiveness of this medication in the treatment against the new coronavirus indicate that the substance blocked the enzyme responsible for the replication of the virus inside the cells.

So, as with other medications, there is nothing effectively proven . These are studies and analyzes of some isolated cases.


Nitazoxanide is a medicinal substance that acts as an active ingredient in remedies (antiparasitic) used to treat diseases such as:

  • Viral gastroenteritis – inflammation of the gastrointestinal tract that affects the stomach and small intestine;
  • Helminthiasis (verminosis);
  • Amoebiasis – parasitic infection of the colon;
  • Giardiasis – intestinal infection caused by the giardia parasite;
  • Cryptosporidiasis – infectious disease caused by parasites, which affects the gastrointestinal system.

Although the document published by the Ministry of Health does not mention this medication, it has been tested by researchers for the treatment of the new coronavirus.

In this sense, what is known is that in some analyzes, it was possible to note that the use of Nitazoxanide has shown to be effective in reducing the viral load of SARS-CoV-2. As a result, after in-vitro testing, testing on humans began – including in Brazil.

There is still no further evidence of the efficacy of this remedy. Considering that it is undergoing tests and studies.

Understanding how the virus works and studying drugs used to treat illnesses caused by it can help to reduce anxiety waiting for treatment for Covid-19.

We hope that this article may have been enlightening and reinforce: do not practice self-medication. Follow the guidelines of the Ministry of Health regarding preventive measures and care in case of contamination.

Keep following the Healthy Minute for more information!