With colds – bacteria increase the leukocytes – viruses lead to low values:
With a cold, the leukocytes are increased if it is a bacterial infection. The immune system tries to fight the foreign bodies. Therefore, the human organism produces a large number of white blood cells. If the leukocytes are low when you have a cold, it is a viral infection. There is severe wear and tear of the white blood cells , so that the post-production does not take place quickly enough. Because of this, leukopenia develops within the body .
Bacteria cause an increase in the number of leukocytes
If bacteria infect the body, the immune system works at full speed. When a cold occurs, various foci of inflammation develop in the organism of the person affected. If there is an increase in the number of leukocytes, doctors suspect acute inflammation.
This is the case, for example, when the common cold is followed by pneumonia. Furthermore, the white blood cells proliferate when secondary bacterial infections occur. The immune system reacts to the large number of bacteria in the body by increasing the number of leukocytes. This condition is called leukocytosis .
In a large blood count, doctors can see the proliferation of white blood cells at first glance. The normal value of leukocytes in a healthy adult is up to eleven million white blood cells per microliter of blood. With a cold caused by bacteria, this number increases to 12 to 15 million in a microliter of blood. If the leukocytes are increased during a cold, it is usually a special subgroup of these cells .
In a differential blood count , the experts clearly see an increase in neutrophilic granulocytes . These make up almost 80 percent of the white blood cells in the body. Accordingly, in this case there is granulocytosis. If these leukocytes are increased during a cold, this is due to the greater consumption due to the defense against infectious agents. Several preforms of leukocytes proliferate in the same case. Doctors observe this phenomenon, known as left shift, in a blood count.
Normally, viruses are responsible for the majority of infections during the cold season. The body’s own immune system fights them by increasing the number of white blood cells. Nevertheless, the number of leukocytes is low when you have a cold. This is due to a very high consumption of white blood cells due to the defense against infection. The formation of new cells from the bone marrow does not happen quickly enough, resulting in a significant reduction in the number of leukocytes. Doctors call this condition leukopenia.
Viruses cause leukopenia because of their properties
This cytopenia affecting the white blood cells is also due to the viruses. They possess immunosuppressive properties. This means that they suppress the normal functioning of the immune system. In addition, viruses are not living beings, so antibiotics do not help the patient with a viral infection.
Doctors still prescribe these drugs to prevent secondary bacterial infection. If the leukocytes are low during a virus-related cold, the immune system is weakened. That is why antibiotics protect the body against bacteria, but do not fight viruses.
Chronic inflammation causes leukopenia
Only after the immune system has successfully defended itself against the viral pathogens are new white blood cells formed. In this case, there is a strong increase in lymphocytes, a lymphocytosis. In addition to viral infections, there are other reasons for the low concentration of leukocytes in the blood. This includes:
- chronic inflammatory processes,
- impaired production of white blood cells
- or damage to the bone marrow.
Furthermore, there are few bacterial diseases that result in a reduction in the leukocyte concentration in the blood. Examples of these diseases caused by bacteria include typhus. To avoid additional infections, there are ways to increase the leukocyte count again. Sports such as swimming have a positive effect on the production of white blood cells.
A summary of altered leukocyte counts in the common cold
If those affected become infected with a viral disease, the number of white blood cells in the organism decreases. The reason is an increased consumption of leukocytes, so that the post-production does not work fast enough. In addition, numerous viruses have properties that prevent rapid regeneration of white blood cells. With a bacterial cold, there is an increase in leukocytes. Here, the immune system works more intensively and produces a large number of neutrophilic granulocytes .
