How long after a fever should one get a blood test for the most accurate results?
Apr 06, 2023
Source: Cainiu Health
Dr. Yang Shuwen
Introduction
Fever refers to an elevated body temperature. Blood tests are generally more accurate if conducted after 24 hours of fever onset, helping to identify the underlying cause and guide appropriate treatment. Fever can be caused by various factors, such as wind-heat感冒 (a TCM term for certain types of colds), upper respiratory tract infections, and others. It is necessary to undergo a systematic evaluation at a hospital to determine the specific cause and choose the appropriate treatment accordingly.
Fever refers to an elevated body temperature. Blood tests are generally more accurate after 24 hours of fever onset. Based on test results, the underlying cause can be identified and appropriate treatment initiated.
Fever occurs when the body's thermoregulatory center is affected by various factors, leading to dysfunction, excessive heat production, reduced heat dissipation, and consequently a body temperature above the normal range. White blood cells are immune cells that become activated when the body is invaded by bacteria or viruses, actively fighting these pathogens. During blood tests, white blood cell counts typically show a significant increase. However, it usually takes about 24 hours for white blood cells to fully mobilize. Therefore, conducting blood tests 24 hours after the onset of fever allows for a more accurate assessment of the body's response to infection, helping to preliminarily determine whether the infection is bacterial or viral and assess the severity of the illness.
In addition, fever can result from various causes, such as wind-heat感冒 (a term in traditional Chinese medicine), upper respiratory tract infections, and others. It is important to seek comprehensive medical evaluation at a hospital. Treatment should be tailored according to the specific underlying cause. In daily care, it is recommended to drink plenty of water, get adequate rest, and undergo proper treatment, through which fever will gradually return to normal.
