The novel coronavirus, now named COVID-19, was declared a pandemic on March 11, 2020. It is the sixth pandemic named in about a century. So when does a disease become a pandemic, and what does the designation mean for governments and markets? CNBC’s Tom Chitty explains. ----- Subscribe to us on YouTube: http://cnb.cx/2wuoARM Subscribe to CNBC International TV on YouTube: https://cnb.cx/2NGytpz Like our Facebook page: https://www.facebook.com/cnbcinternational Follow us on Instagram: https://www.instagram.com/cnbcinternational/ Follow us on Twitter: https://twitter.com/CNBCi