Iterative Excretion of Human Cosaviruses from Different Genotypes Associated with Combined Immunodeficiency Disorder

Human cosaviruses (HCoSVs) are newly discovered enteric viruses in the Picornaviridae family. They have been described in non-polio acute flaccid paralysis, diarrheal patients, and healthy individuals. They remain rarely documented in immunodeficient patients.

This study reports iterative excretion of HCoSVs in a patient with major histocompatibility complex (MHC) class II combined immunodeficiency, a relatively common primary immunodeficiency in consanguineous settings.

A total of 35 samples were collected from a patient followed for oral polio vaccine strains detection in stool samples during a 57-month period. Detection of HCoSVs in stools was performed by nested RT-PCR in the 5' noncoding region. The genotype identification and screening for recombinant strains was performed by sequencing in the VP1 and 3D genomic regions followed by phylogenetic analysis.

The patient was infected with HCoSVs twice at a 3-year interval. The excreted viruses belonged to 2 different genotypes with 2 probable recombinant viruses. During HCoSV infections, the patient was also excreting Sabin-related polioviruses.

This study describes excretion kinetics and genetic characteristics of HCoSVs in a patient with combined immunodeficiency due to MHC class II expression defect. The patient did not have concomitant symptoms related to the HCoSV infection.