Children with certain immunodeficiency diseases carry mutations in their genes that regulate the body’s immune system against viral infections. They have a higher mortality rate due to Covid-19 complications.
Immunodeficiency results from the failure or absence of elements in the immune system of the body, such as lymphocytes and phagocytes. These immunodeficiencies can be primary or secondary.
A study on this was conducted by researchers from Karolinska Institutet, and published in the Journal of Allergy and Clinical Immunology. It indicated that most children infected with the SARS-CoV-2 coronavirus often show mild illnesses or no symptoms.
However, a small percentage of children with immunodeficiency, who have abnormalities in genes that regulate the body’s immune system viral infections, have a higher death risk.
“Mortality is much higher among children with primary immunodeficiency diseases infected with SARS-CoV-2. Our results indicate that basic immunological examination and genetic analysis should be conducted in children with severe COVID-19 or multi-inflammatory syndrome (MIS-C). The clinicians will then be able to help these children with more precise therapies based on their genetic changes,” said Qiang Pan-Hammarstrom, professor at the Department of Biosciences and Nutrition, Karolinska Institutet, who led the study.
For the study, 31 children and teens between the ages of five months to 19 years were included. Each child had some type of primary immunodeficiency disease without a molecular diagnosis and suffered from severe or critical Covid-19. The participants were recruited from August to September 2020 in Iran. None of them were vaccinated against Covid-19.
One-third of the participants, 11 children, died of complications from the infection. Five children, 15 percent, had multi-inflammatory syndrome (MIS-C). Some of them lacked antibodies to the coronavirus.
“This suggests that many children with this type of immune disease cannot produce antiviral antibodies and therefore would not have the full benefit of vaccination,” said Hassan Abolhassani, assistant professor at the Department of Biosciences and Nutrition, Karolinska Institutet, and the study’s first author.
The genetic analyses showed that more than 90 percent of the participants, 28 children, had mutations in their genes that are important for our immune defense system, which could explain their immunodeficiency.
The study, funded by the Swedish Research Council and the Knut and Alice Wallenberg Foundation, also included a literature review where researchers found reports of around 1,210 patients with primary immunodeficiency disease and Covid-19 and 30 percent of them being children.
While the study is limited only to severe cases of Covid-19 where the children are infected with the original strain of the virus and are non-vaccinated, further research is needed to evaluate the importance of different virus variants and vaccines in this group.