Deferred Revenue

12 Months Ended

Dec. 31, 2021

Deferred Revenue [Abstract]

Deferred Revenue

15. Deferred Revenue

Current deferred revenue included $79,718 of advances from customers (December 31, 2020 - $363,787) and $223 from the PRC government for stockpiling of H5N1 and hepatitis A vaccines (December 31, 2020 - $218). The Company’s deferred revenue balances change due to timing of advance payments received from customers and timing of delivery of products to customers.