Association between selective IgA deficiency and COVID-19

Yuji Naito; Tomohisa Takagi; Tetsuro Yamamoto; Shaw Watanabe

doi:10.3164/jcbn.20-102

Association between selective IgA deficiency and COVID-19

J Clin Biochem Nutr. 2020 Sep;67(2):122-125. doi: 10.3164/jcbn.20-102. Epub 2020 Aug 21.

Authors

Yuji Naito¹, Tomohisa Takagi¹, Tetsuro Yamamoto², Shaw Watanabe³

Affiliations

¹ Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto 602-8066, Japan.
² TTC Co. Ltd., 1-20-2 Ebisu-nishi, Sibuya-ku, Tokyo 150-0021, Japan.
³ Asia Pacific Clinical Nutrition Society, Life Science Promoting Association, 25-3-1004 Daijyo-cho, Shinjuku, Tokyo 160-0015, Japan.

Abstract

The purpose of this study was to propose a hypothesis that there is a potential association between the incidence of selective IgA deficiency in various countries and COVID-19 cases. The number of deaths due to COVID-19 increased in clear proportion to the number of infected patients, and the difference in the number of deaths by country was due to the difference in the number of infected patients. The frequency of selective IgA deficiency has a strong positive correlation with the prevalence of COVID-19 per population. The low infection rate contributed to the low death rate from COVID-19 in Japan, suggesting that the extremely low frequency of selective IgA deficiency may be a contributing factor.

Keywords: COVID-19; IgA deficiency; mortality.