Int J Family Med Prim Care | Volume 1, Issue 3 | Review Article | Open Access

Host Factors That Aggravate COVID-19 Pneumonia

Shaw Watanabe1*, Yuji Naito2 and Tetsuro Yamamoto3

1Asia Pacific Clinical Nutrition Society, Japan 2Department of Gastoenterology, Kyoto Prefectural University of Medicine, Japan 3TTC Co. Ltd, Japan

*Correspondance to: Shaw Watanabe 

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The cumulative number of COVID-19 patients per 100,000 population units varies between countries: Spain and Italy have more than 30, many European countries have between 10 and 20, and East Asian countries have 0.1 to 0.3. Various host factors can influence the mortality, but innate immunity prevails at the initial stage of infection. IgA and secretory IgA are responsible for the immunity in the oral cavity and intestinal tract. IgA deficiency is common in Europe and the United-States, while it is very rare in Japan. This difference may explain differences in the number of deaths by COVID-19. Developing countries will remain affected by the pandemic for a few more years. Predicting severity is important, and sIgA measurement in saliva seems to be simple and costeffective. Intestinal Microbiota and metabolites like butyrate are also related to the innate immunity. Brown rice eaters show an ideal symbiotic composition of Microbiota to build innate immunity.


Covid-19; Covid; Corona Virus; Coronavirus disease 2019


Watanabe S, Naito Y, Yamamoto T. Host Factors That Aggravate COVID-19 Pneumonia. Int J Fam Med Prim Care. 2020; 1(3): 1011.

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