The main clinical symptoms and syndromes of infectious diseases

Diseases caused by pathogenic microorganisms (fungi, viruses, bacteria) are called infectious. The susceptibility of a person to them depends on many factors: age, chronic diseases, vaccination, food culture. To recognize the infection on time, you need to know what symptoms and syndromes correspond to it.

Infectious Disease Syndromes

The infectious process includes the interaction of three factors in the human body: the environment, the macroorganism and the pathogen (parasitic, fungal, viral). It manifests itself at the cellular, subcellular, organ, molecular tissue level, naturally ending with either release from the pathogen, or death of a person. The main clinical syndromes for infectious diseases:





Rhinovirus infection

Adenovirus infection


Sharp deterioration




Signs of intoxication

Pain in the eyes, neck, muscles, headache, throbbing, febrile temperature up to 39 ° C

Not very pronounced, general weakness, headache, low-grade fever

Mild, no temperature

Weakness, headache, prolonged high fever

Catarrhal manifestations

Dry cough, sore and dry throat, nasal congestion, intracranial hypertension

From the first hours, a hoarse voice, dry cough, pain when swallowing

Rhinorrhea, sneezing, runny nose

Pronounced rhinorrhea, swelling of the tonsils, plaque on the tongue, hyperemia of the pharynx


Neurological lesions, acute bronchitis, pathologies of the heart, blood vessels, kidneys, Reye syndrome

Exacerbation of COPD and BA, acute bronchitis

Sinusitis, otitis media

Lacunar angina, myocarditis, otitis media, sinusitis


Inflammation and swollen lymph nodes indicate active proliferation of lymphoid cells. In addition to changes in the lymph nodes, the following clinical symptoms are observed with lymphadenopathy:

  • causeless weight loss;
  • increased hepatomegaly and splenomegaly;
  • bouts of fever;
  • heavy sweating;
  • purulent rashes on the skin (blisters, papules, blisters, ulcers, pustules);
  • high body temperature.

Convulsive syndrome

A non-specific reaction of the human body to an internal or external stimulus with an involuntary attack of muscle contractions is called a convulsive syndrome. Seizures are observed in patients with meningitis. Inflammation of the meninges is caused by fungi, rickettsia, viruses, and bacteria. Clinical convulsive syndrome is characterized by muscle relaxation, short-term spasms. They begin with the face, then capture the hands, fingers, forearms, shoulders, legs.

Meningeal syndrome

It occurs due to irritation by external or internal factors of the meninges. Meningeal syndrome or meningism occurs with intoxication, tumors, hypoxia, and inflammatory diseases. General hyperesthesia is accompanied by sensitivity to light and sound stimuli, tension of the masticatory muscles and stiff neck, subarachnoid hemorrhage and other cerebrospinal fluid symptoms can occur. When trying to bend the patient's head, a sharp pain overtakes. When one leg is extended, the second bends involuntarily.

Fever syndrome

The essence of febrile syndrome is that human thermoregulation responds to pyrogens - non-specific substances. As a result, the temperature is shifted to a higher level, while maintaining the mechanisms of thermoregulation. The most common causes of high temperature are parasites, infectious pathogenic viruses, microbes and their metabolic products. Common symptoms of fever syndrome:

  • confusion, delirium;
  • intense sweating, trembling, chills;
  • poor appetite;
  • bone aches;
  • unmotivated bad mood;
  • rapid breathing;
  • redness of the skin of the face;
  • thirst.

Exanthema syndrome

A viral infection that occurs in infants and young children. Initially, exanthema syndrome is characterized by fever without local symptoms. After appear rubella-like rashes on the skin. Exanthema has other names: pseudo-rubella, roseola, sixth disease. Viral exanthema is manifested by a rash that occurs when the temperature drops. Rashes appear on the body, gradually spreading to the neck, face, upper and lower limbs. Symptoms persist for up to 3 days, after which they disappear without a trace.

Sore throat syndrome

Symptoms and syndromes of infectious diseases are mainly manifested by high fever and intoxication. An epidemiological history indicates the main signs: patient agitation or lethargy, vesicular-pustular rashes, pale nasolabial triangle, enlarged spleen or liver. Catarrhal syndrome in infectious diseases is a sign of acute tonsillitis (tonsillitis), tracheitis, pharyngitis, laryngitis, flu. Its clinical manifestations correspond to diffuse catarrh of the respiratory tract (upper).

General toxic syndrome

Bacteriological methods for diagnosing infectious diseases help to identify the causative agent (biochemical blood test), but the doctor will make a diagnosis faster, based on the manifestations of the general toxic syndrome. For the pathological condition of a patient with an infection, symptoms such as chills, drowsiness, and various types of fever are characteristic. General toxic syndrome in infectious diseases is characteristic of the following infections:

  • encephalitis;
  • plague;
  • measles;
  • typhoid fever;
  • pseudotuberculosis;
  • mononucleosis;
  • toxoplasmosis.

Jaundice syndrome

With many infectious diseases, jaundice syndrome manifests itself. Hepatic pathologies of any etiology are accompanied by this symptom (hepatitis A, B, C, E, hepatosis, cirrhosis). A patient with icteric syndrome has an orange-red or saffron-yellow skin pigment, since the pathological process is localized in hepatocytes. Subjectively expressed malaise and liver failure of varying degrees.

Diarrhea syndrome

The most common symptom that accompanies many diseases. Diarrhea syndrome is characterized by an increase in stool volume of a watery consistency, reverse absorption of gases. When it is difficult for fatty acids to enter the gastrointestinal tract, the bowel movements become greasy and become acholic. Lightning fast diarrhea suggests acute intestinal infections. Bloody loose stools are the first manifestation of Crohn's disease, diphtheria, or ulcerative colitis. Chronic diarrhea is observed in the pathology of the digestive system.

Symptoms of Infectious Diseases

Regardless of the type of pathogen, signs of infection appear approximately the same. The onset of the disease is preceded by intoxication, which combines malaise, muscle pain, fever, migraine. All painful symptoms begin due to:

  • weakened immunity;
  • sedentary activity;
  • lack of vitamins;
  • dysbiosis;
  • seasonal hypothermia;
  • regular anxiety, stress;
  • unbalanced nutrition;
  • blood transfusion;
  • contact with an infected person.

First symptoms

An integral sign of infection in the body is the presence of an incubation period. The duration of incubation depends on the type of pathogen, and it varies. With SARS and influenza, it is 1-2 days with HIV - 10 years. The first symptoms of an infectious disease appear at the end of the incubation period, which is determined by the nature of the immune response and the aggressiveness of the agent. After incubation, the prodromal period begins, in which the patient already knows that he is unwell. This phase can last from 1 to 10 days. It is difficult to make a diagnosis at this stage.

Common symptoms

By classification, infections are divided into intestinal, viral, bacterial, fungal and parasitic. Often they are divided according to the location of pathogens and the method of infection. Infections always begin in the same way, but the peak of the illness can take place in different ways, depending on the type of pathogen. For example, if the lymph nodes increase, then the doctor may consider mononucleosis or a sexually transmitted disease. Vomiting develops in diseases such as scarlet fever, erysipelas, and typhus. General symptoms of infection appear only in the first phase of the disease.

Symptoms of infectious diseases in children

The child is always infected from a sick person. Since it is difficult to obtain information about the state of health from him, it is possible to diagnose the disease based on the symptoms of childhood infectious diseases. For example, a phlegmonous omphalitis, a pediatrician recognizes by peeling and crusts (scabs) of the skin around the navel, and axillary lymphadenitis - by inflamed lymph nodes. Recently, often among children there are atypical rotavirus strains with such signs:

  • stagnant stool;
  • skin pigmentation;
  • spots on the oral mucosa;
  • damage to the oropharynx.

Symptoms of Dangerous Infectious Diseases

Dangerous infections that can be fatal include hemolytic anemia, meningococcal sepsis, tetanus, whooping cough, and hemorrhage. Symptoms of dangerous infectious diseases are different, but they all have high risks of complications. In the first place in mortality in the world is HIV infection, in the second - tuberculosis, in the third - diphtheria.

Symptoms of Sexual Infectious Diseases

Pathologies of the reproductive system are dangerous due to their asymptomaticity in the first phase after infection. For example, syphilis may not occur for six months, and staphylococcal infection - up to 10 days. Common symptoms of genital infections:

  • mucus and cheesy discharge;
  • lymph nodes in the inguinal region;
  • suppuration of the skin;
  • genital bleeding;
  • pain during urination;
  • itching, burning, pain in the urinary system.

Video: diagnosis of infectious diseases

Attention! The information presented in the article is for guidance only. Materials of the article do not call for independent treatment. Only a qualified doctor can make a diagnosis and give recommendations for treatment based on the individual characteristics of a particular patient.

Watch the video: Vaccine and infectious disease updates: Mayo Clinic Radio (April 2020).