Accounting for Symptomatic and Asymptomatic in a SEIR-type model of COVID-19 Jayrold P. Arcede, Randy L. Caga-anan, Cheryl Q. Mentuda and Youcef Mammeri Math. Model. Nat. Phenom., 15 (2020) 34 Published online: 19 June 2020 DOI: 10.1051/mmnp/2020021