Older age is associated with sustained detection of SARS-CoV-2 in nasopharyngeal swab samples. Issue 1 (January 2021) - Hattori, Takeshi; Amishima, Masaru; Morinaga, Daisuke; Kamada, Keisuke; Nakakubo, Sho; Yamashita, Yu; Shichinohe, Yasuo; Fujisawa, Shinichi; Nishida, Mutsumi; Nasuhara, Yasuyuki; Teshima, Takanori; Konno, Satoshi