The Koronavirusny infection, as well as many other acute respiratory diseases, has no accurately specific clinical picture. Symptoms of this disease can meet also at other pathology. On the other hand, COVID-19 has big variability of clinical forms of course, beginning from completely asymptomatic current and finishing with multiorgan insufficiency.
In the context of a pandemic there is a tendency to consider any manifestation of a respiratory disease of a symptom of a koronavirusny infection that it can also lead to hyper diagnostics of this disease and late diagnostics of other pathologies, especially from among similar in a clinical picture. The possibility of carrying out a research of material from the patient on existence of a coronavirus of new type in it not always resolves an issue as the delayed receipt of the answer from laboratory and also existence of an asymptomatic course of a koronavirusny infection with simultaneous development of other disease can take place.
Thus, differential diagnostics of a koronavirusny infection plays a special role and it is always necessary to remember existence of other similar diseases that is especially important in the conditions of a pandemic.
Basic diseases with which it is necessary to differentiate COVID-19: flu, acute respiratory viral infections which are caused by viruses from the SARS group (for example, rhinoviruses, adenoviruses, the RS-virus, human metapneumoviruses, MERS-CoV, a parainfluenza virus), a viral gastroenteritis, bacterial respiratory infections, tuberculosis.
Incubation interval duration can become one of starting points for carrying out differential diagnostics. It becomes possible to consider if the contact with the diseased is come. Incubation interval duration at a koronavirusny infection averages from two to fourteen days (there were messages about separate cases of duration of an incubation interval up to 21 days), but in general the majority of cases keep within an interval from five to seven days. At the same time, incubation interval duration at a SARS and, in particular, at flu, usually does not exceed three days. The disease debut differs a little too: at flu the symptomatology begins sharply, and at a SARS more gradually.
When comparing fever it must be kept in mind that both at flu, and at a koronavirusny infection high fever can be noted that distinguishes them from a SARS when high temperature meets rather seldom. Also the weakness is more characteristic of flu and a koronavirusny infection, than of a SARS.
Typical symptom for a koronavirusny infection is breath difficulty. This symptom is not characteristic neither of flu, nor of a SARS. Difficulty of breath at flu or a SARS can appear a little later than, as a rule, in case of accession of consecutive infection (pneumonia).
The symptomatology of a new koronavirusny infection and tuberculosis can be similar as in both cases defeat of a respiratory system takes place. At the same time, symptoms of tuberculosis appear in most cases gradually though the acute beginning of this pathology can take place too. Also it is not necessary to exclude a possibility of existence at the patient at the same time of two diseases. Tuberculosis is confirmed by identification in a phlegm of acid resisting bacteria with the subsequent allocation of culture and also the test of identification of effector T lymphocytes which react to stimulation by tubercular antigen (ELISPOT method). Identification of markers of DNA of a tubercular stick by PTsR method is also possible. From diagnostic testings the X-ray analysis of lungs is of great importance.
At differential diagnostics of a koronavirusny infection and viral gastroenteritis it must be kept in mind that at a viral gastroenteritis the gastrointestinal tract disease will be leading, and symptoms from respiratory tracts are usually expressed in small degree.
It is necessary not to forget that in all doubtful cases carrying out inspection on detection of a coronavirus is shown. Speed of obtaining the answer from laboratory and also a possibility of carrying out rapid tests is of very great importance. At the same time, all existing tests have a certain percent of an error therefore assessment of a clinical picture and dynamics of a course of a disease continues to remain an important factor for statement of the correct diagnosis.