The number of mild to moderately symptomatic cases of COVID-19 between April 1 to April 15 could range between two million and seven million globally, according to catastrophe risk modelling firm AIR Worldwide. The number of severe cases worldwide could range between one million and three million, with anywhere from 70,000 to 230,000 deaths.
According to a Wednesday report by the World Health Organisation (WHO), confirmed cases have been reported in 205 countries, areas and territories. The outbreak in the US has surpassed both China and Italy, with 163,199 confirmed cases and 2,850 deaths, according to the WHO. Estimates from Johns Hopkins University and others place US numbers even higher, according to AIR Worldwide.
Italy has 101,739 reported cases and 11,591 deaths, according to AIR Worldwide. Italy’s rise in case numbers may be slowing, however, as a result of the country-wide lockdown. Spain’s outbreak has also surpassed China, with 85,195 cases and 7,340 deaths. China has reported 82,631 cases and 3,321 deaths. However, the number of new cases in China has reportedly fallen to just a few per day due to the country’s aggressive containment measures, AIR Worldwide reported.
The next largest outbreak is in Germany, with 61,913 cases and 583 deaths, followed by Iran with 44,606 cases and 2,898 deaths.
“Based on the estimations and projections from the AIR Pandemic Model, we estimate that this may represent a moderately conservative projection of cases; the vast majority will be asymptomatic or have mild symptoms,” said Dr. Narges Dorratoltaj, principal scientist at AIR Worldwide. “The difference between the low and high ends of the range is driven by a few factors. Uncertainty in the reported number of confirmed cases and the transmissibility of the virus play a significant role. Specifically, the lower end of the range represents a scenario where (a) the true number of cases is relatively closer to what has been reported than estimated, and (b) the possibility that containment measures (such as isolation and quarantine) become more successful than they have been to date. If such containment measures – driven by international and/or local authorities – are successful, this could restrict the human-to-human transmission sufficiently to bring the eventual number of cases to or even below the low end of the modelled projected range of cases.”
AIR Worldwide’s estimates account for uncertainty and underreporting. While mild to moderate cases are the least likely to be reported, there will likely be significant underreporting even for severe cases and deaths. As of Wednesday, there were 783,360 confirmed cases of COVID-19 worldwide and 37,203 deaths.