Fever is an important mechanism for fighting infections, especially in warm-blooded animals, as it improves the function of T lymphocytes. Now, in a study published in PNAS magazine, researchers have shown that cold-blooded vertebrates also heat the body to achieve this effect. For this, they move to warm waters, which is known as behavioral or behavioral fever.
Researchers have shown this behavior with Nile tilapia, which has been launched into the attack. In particular, tilapias infected with the Edwardsiella piscicicicide bacteria have been found to target the area where water is hotter and stop eating. In this way, energy is directed against infection, and in addition, increasing temperature causes changes in the immune system: slowing down the production of enzymes that destroy T lymphocytes, increasing the transcription of nitric oxide (a powerful antimicrobial) and generating proteins that cause inflammation. In addition, high temperatures prevent the growth of certain viruses and bacteria.
They have also explained that this body warming strategy was developed millions of years before the appearance of warm-blooded animals.
Finally, they have recalled that increasing body temperature (from fever or displacement to hot places) is essential to improve immune function and fight infections.