Angina is a disease familiar to everyone from childhood. We all know that this is an acute respiratory disease (acute respiratory disease), accompanied by severe sore throat and fever. The best cure for sore throat, according to most, is antibiotics. But is it? Should you rush to the pharmacy for an antibiotic when faced with symptoms of sore throat?
In fact, what we call a sore throat is not always caused by a bacterial infection. Acute tonsillitis (and this is how angina is commonly called in medical practice) can be caused by both bacterial and viral activity. Often, acute tonsillitis is called a viral disease, and angina is called bacterial, but this is not generally accepted.
In most cases, tonsillitis develops as a result of an acute viral infection (i.e., a cold), and a bacterial infection joins as a complication.
Less often (but there are also such cases), inflammation of the tonsils is associated with a fungal infection.
As you know, antibiotics do not affect the vital functions of viruses. Thus, in some cases, the symptoms of angina are not a reason to start active antibiotic therapy. But how to distinguish viral sore throat from bacterial? Read about it in our article.
Viruses and bacteria that cause sore throat
In order to more clearly show the differences between viral and bacterial tonsillitis, let us briefly clarify what fundamental differences exist between their causative agents - viruses and bacteria.
Viruses are infectious agents of extremely small size and simple structure. In fact, it is a DNA strand that integrates into a human cell and forms thousands of copies of itself. In this case, the work of the human cell is disrupted, which causes certain symptoms. For example, with tonsillitis, the virus multiplies in the cells of the tonsil mucosa.
A viral infection rarely occurs in isolation: it spreads to the mucous membrane of the nasopharynx, eyes, etc. Therefore, ARVI is characterized by the simultaneous appearance of a runny nose, cough, sore throat, conjunctivitis.
The virus does not feed on body tissues, does not form colonies. Its task is to create as many copies as possible and
infect all cells that are nearby. That is why viruses are so contagious, but they disrupt human health for only a few days. The virus cannot multiply outside the human cell. And in general, it is rather difficult to call a virus alive outside a human cell - it is a completely inactive molecule.
Viruses that can cause tonsillitis:
- adenoviruses;
- parainfluenza;
- Coxsackie virus;
- RS virus;
- Epstein_Barr virus (EBV, or EBV).
About a third of cases of acute tonsillitis are of bacterial origin. In 90% of them, the causative agent of the infection is group A streptococcus.
Bacteria, unlike viruses, are full-fledged living organisms. The human body plays the role of a breeding ground for them - they feed on body molecules, form colonies, try to resist immune defenses and treatment. Bacteria do not invade the cells of the body, but multiply on their surface. Unlike viruses, they spread within a limited area of the body (for example, multiply on the surface of the tonsils, causing a sore throat). At the same time, they damage cells and cause a violent protective reaction on the part of the body - an increase in temperature, the formation of pus, etc.
Bacterial infections are usually more severe than viral infections and are more likely to lead to complications. In addition, bacteria can inhabit the body for a long time. So, chronic bacterial infections last for years.
Differences in the clinical picture with tonsillitis
The clinical picture of acute tonsillitis can give some idea of the nature of the pathogen. In determining the causes of the disease, both external symptoms and data from pharyngoscopy (examination of the throat) play a role.
It is worth noting that examination is not always sufficient to provide a diagnosis. First of all, this is due to the fact that the clinical picture of bacterial and viral tonsillitis has many similarities:
- the disease begins acutely, unexpectedly;
- body temperature rises (up to 39-40 ° C);
- sore throat worried;
- when examining the throat, enlarged reddened tonsils are noticeable;
- often the tonsils are covered with a loose coating.
Table 1 shows the characteristic features of the clinical picture of viral and bacterial tonsillitis.
| Sign | ARVI | Epstein-Barr virus | Streptococcus |
| Body temperature | in children it can reach 39 ° C | in most cases, subfebrile (about 37 ° C) | always above 38 ° C; in children - 39-40 ° С |
| Antibiotic reaction | the effect is weak or absent | the positive effect is weak or absent; when taking ampicillin or amoxicillin, the patient may develop a skin rash | after 12-24 hours the body temperature returns to normal |
| Sore throat type (predominantly) | catarrhal form - a weak, mucous or mucopurulent plaque, moderate sore throat | catarrhal, with a loose coating or transparent mucus on the tonsils | follicular tonsillitis - plaque in the form of yellowish dots, acute pain when swallowing; lacunar - purulent plaque filling the lacunae |
| Conjunctivitis | with adenovirus infection - in 100% of cases | observed in less than 10% of cases | observed in less than 10% of cases |
| Other symptoms of acute respiratory infections | cough, runny nose, pharyngitis (plaque is visible on the visible part of the back of the throat) | runny nose, nasal voice, enlargement of the mandibular lymph nodes | accompanying symptoms are minimal (a characteristic difference between bacterial sore throat and viral sore throat) |
| Possible complications | viral tonsillitis can rarely be complicated by a bacterial infection; | sometimes - otitis media, pneumonia, neuritis, bacterial tonsillitis | otitis media, laryngitis, rheumatism, nephritis |
Table 1 Comparison of symptoms of viral and bacterial acute tonsillitis.
To accurately determine the causative agent of the disease, it is necessary to pass some tests (first of all, a general clinical blood test and bacteriological culture).
When making a diagnosis, the epidemiological picture, the fact of contact with infectious patients, the duration of the incubation period, etc. are also taken into account.
Differences in the blood test
The best way to determine if your sore throat is viral or bacterial is to have a CBC. This is a universal analysis that sheds light on the processes taking place inside the body. Table 2 shows the key changes in CBC scores for viral and bacterial angina.
| Index | viral sore throat | bacterial sore throat | norm |
| Leukocytes, g / l | with ARVI is normal, with EBV it can be significantly higher than normal | level increased | 4-9 |
| ESR (erythrocyte sedimentation rate) | increased | increased | F-2-15 M-1-10 |
| Neutrophils | normal or below normal | level increased | stab - 1-6%, segmented - 47-72% |
| Lymphocytes | level increased | below normal | 19-37% |
| Monocytes | with ARVI, the level is normal; with EBV - significantly increased | fine | 3-11% |
Tab. 2 Indicators of a general clinical blood test for bacterial and viral infections on the example of acute tonsillitis.
If you suspect streptococcal sore throat, it is recommended to take a blood test for antibodies to streptococcus - ASLO titer. An elevated ASLO titer confirms streptococcal infection.
If the symptoms indicate the presence of the Epstein-Barr virus in the body, it is recommended to take a blood test for antibodies to the capsid antigen (VCA, IgM and IgG). Also, the presence of this virus can be judged by the presence of its DNA in the patient's saliva. This can be determined using PCR analysis.
Bacteriological diagnostics
How to tell if you have a viral or bacterial sore throat? Another sure method is to pass a bacteriological culture of a throat swab. With a sterile gauze or cotton swab, the health worker passes over the tonsils, collecting plaque. Then the tampon is immersed in the transport medium and delivered to the microbiological laboratory. The doctor-laboratory assistant sows the bacteria contained on the tampon on a special nutrient medium. After 3-5 days, the microbiologist will be able to determine what types of bacteria are present in the microflora of the patient's throat.
Bacteriological diagnostics also allows you to determine the sensitivity of the identified bacteria to antibiotics. By sowing a culture of bacteria on nutrient media with various antibiotics, the microbiologist will make a conclusion about which of the antibiotics destroys the bacteria most effectively. In most cases, streptococci are highly sensitive to penicillins and cephalosporins; while in 40% of cases, streptococcus reveals resistance to tetracyclines.
The indisputable advantage of bacteriological analysis is its accuracy and information content. At the same time, a significant disadvantage of this method is the impossibility of obtaining a result in a short time.
