Even mild Covid can generate antibodies against the patient, says study

Mild cases of Covid-19 can produce antibodies responsible for attacking cells, organs and tissues in the bodies of those who have been infected even after months of recovery.

Called autoantibodies, they arise in the immune system and are responsible for various autoimmune disorders such as lupus, rheumatoid arthritis, multiple sclerosis and others.

When a person is infected with a virus, the immune system differentiates the body’s proteins from foreign proteins and thus develops antibodies.

Sometimes, however, people produce autoantibodies, which have the ability to attack the human body instead of doing the usual job of antibodies, which is to protect it.

The finding was disclosed in a study published in the Journal of Translational Medicine by researchers at Cedars-Sinai Hospital.

The study was conducted with a group of 177 health professionals, 65% women and 45% men, with an average age of 35 years, who have been proven to have developed Covid-19. The volunteers were taken from a health care company in Los Angeles, in the United States.

As a control group, the researchers used samples that had been taken before the start of the coronavirus pandemic from 53 healthy people. Of these, 49% were women and 51% men.

All those who had already developed the disease had high levels of autoantibodies. Some were the same types as those found in autoimmune diseases in which the immune system attacks its own cells, such as lupus and rheumatoid arthritis.

Other studies had already attested to the presence of autoantibodies in moderate and severe cases of Covid-19. This now shows that asymptomatic and mild cases can also result in the creation of this type of antibodies and that the condition persists after infection.

The group was evaluated through a blood sample and a questionnaire that sought to understand which of the 21 symptoms of Covid-19 reported the volunteers had in the six months prior to the blood collection. Disease severity was defined based on the number of symptoms.

If the volunteer felt nothing, he was considered asymptomatic. If he reported from one to seven symptoms, his case was treated as mild. With more than seven symptoms, the case was considered more severe than mild – the study did not determine the number of symptoms for moderate or severe cases.

Justyna Fert-Bober, co-author of the study in the cardiology department at the Smidt Heart Institute, said in an article published on the Cedars-Sinai Hospital website that the results help to understand why Covid-19 is an especially unique disease.

“These patterns of immune dysregulation may underlie the different types of persistent symptoms that we see in people who develop the condition now called long-term Covid-19,” he said.

In the long Covid, people can feel the effects of the disease for months. A British study found that the incidence of prolonged symptoms of the disease was 50% higher in women and twice as common in people over 70 years of age.

The research investigated the ability to create autoantibodies in men and women after infection. While the antibody response of this type was higher in women after asymptomatic infections, it was higher in men when looking at mild cases.

In general, men showed a higher level of autoantibodies than women, especially as the cases worsened. The finding contradicts the common sense about autoantibodies that cause autoimmune diseases, that they often affect women more than men.

On the other hand, the researchers found no statistically significant differences in the symptoms reported by men and women, although some such as fever, shortness of breath, diarrhea, conjunctivitis and chills are more common in men, and others such as loss of appetite, nausea and productive cough. more found in women