What happens during a fever
In response to infection, immune cells release substances that shift the thermoregulatory set point in the brain upward. The body begins to perceive the usual temperature as low: chills and trembling appear, skin blood vessels constrict, the person freezes and wraps himself up until the temperature reaches a new level. Then comes a period of heat, and when the set point decreases, profuse sweating. That is why at the beginning of the ascent it is pointless to open up and wipe yourself with cold water: this only intensifies the trembling. Moderate fever is beneficial and helps the immune system work more efficiently.
- Low-grade fever - up to 38 °C
- Febrile - 38–39 °C
- High – above 39 °C
- Stages of chills, heat and sweating
- Fever of unknown origin lasting more than three weeks
Common reasons
In adults, the leading ones are acute respiratory viral infections and influenza, in which the temperature usually lasts 2–4 days. Next in frequency are bacterial infections: sore throat, sinusitis, pneumonia, urinary tract infections, intestinal infections, inflammation of the gallbladder, skin infections. Fever without obvious catarrhal symptoms should be alarming: it occurs with pyelonephritis, endocarditis, tuberculosis, and abscesses. Non-infectious causes include autoimmune diseases, thrombosis, tumors and drug reactions. Separately, recent trips, contact with animals and characteristics of the profession are taken into account.
- Acute respiratory viral infections and influenza
- Sore throat, sinusitis, otitis media
- Pneumonia
- Urinary tract infections and pyelonephritis
- Intestinal infections
- Skin and soft tissue infections
- Tuberculosis, endocarditis, abscesses
- Autoimmune diseases, tumors, drug fever
When to lower the temperature
The main guideline is how you feel, not the number. If a person tolerates the temperature relatively calmly, drinks and rests, it is not necessary to bring it down. An antipyretic is taken when the fever is painful: severe weakness, aches, headaches, inability to sleep. The issue is addressed separately for people with heart and lung diseases, the elderly and pregnant women: for them, high fever is more severe. A prerequisite for any fever is sufficient drinking, because fluid losses increase. Do not exceed the recommended doses and do not combine several drugs with the same active ingredient.
- Focus on how you feel, not the number
- Drink plenty of fluids at any temperature
- Light clothes and cool air in the room
- Antipyretics at the recommended dose
- Do not combine drugs with the same active ingredient
- Do not rub with alcohol and vinegar
- Pregnant women - only drugs approved by a doctor
What examinations are needed
For a typical viral infection with a runny nose and sore throat, testing is usually not required. Tests are prescribed if the temperature lasts longer than three to five days, there is no obvious focus, the condition is severe, or there are chronic diseases. A complete blood count and C-reactive protein help distinguish bacterial from viral inflammation, and a urine test reveals a urinary tract infection, which in adults is often painless. A chest x-ray is indicated for cough, shortness of breath and suspected pneumonia. In case of prolonged unexplained fever, the examination is expanded according to the plan drawn up by the doctor.
- General blood test with formula
- C-reactive protein
- General urine test
- Chest X-ray
- Ultrasound of the abdomen and kidneys
- Blood and urine cultures if severe infection is suspected
- Testing for tuberculosis and HIV during prolonged fever
Treatment and care
For a viral infection, treatment is supportive: rest, fluids, antipyretics as needed; Antibiotics are useless and harmful. For bacterial infections, the antibiotic is selected by the doctor, and it is important to complete the course in full. Self-administration of antibiotics at every temperature leads to bacterial resistance and complicates future treatment. Rubbing with alcohol and vinegar is strictly not recommended, especially during chills, as well as wrapping up during heat. If the condition worsens during treatment, shortness of breath or confusion occurs, urgent medical attention is needed.
- Rest and plenty of drink
- Antipyretics when you feel unwell
- Antibiotics only as prescribed by a doctor
- Ventilation and cool air
- Light meals according to appetite
- Monitoring the condition and re-examination if it worsens
- Vaccination against influenza and pneumococcus in risk groups
