As we enter the fourth month of the novel coronavirus (Covid-19) epidemic, a shift in the outbreak centres has occurred on a global scale. Disease transmission in China seems to be winding down as reported new cases are decreasing but the virus is just starting to make the rounds in the rest of the world. The World Health Organization’s (WHO) situation reports in the few last weeks showed that there are now more new cases outside of China than in China. The US will likely see outbreak clusters within its own borders during the next few weeks.
In the US, the case count is still extremely low compared to harder-hit countries like China and South Korea, currently at approximately 130 cases with nine deaths. Case reports in New York and California show local transmissions are already occurring though still limited in scope. GlobalData epidemiologists believe the containment status of Covid-19 in the US is likely to change in the coming weeks toward a significant increase in cases.
Several events are coming together to drive the increase, including unchecked travel from Italy, Iran, and South Korea in the weeks before case clusters were found in those countries, the Centers for Disease Control and Prevention (CDC) broadening testing criteria this week, and an increase in capacity to conduct confirmation tests in the US.
Prior to March, the CDC had severely limited testing capabilities. One reason was that the CDC opted to use its own in-house diagnostic test instead of the test developed by Germany and later adopted by the WHO and many other countries. The US-developed kits turned out to have serious operational flaws and were unusable by many laboratories.
The US also set extremely strict requirements to approve testing, including only testing people who had a travel history to China and those in close contact with infected individuals. Let’s put the US’s testing rates in perspective to the rest of the world’s: the CDC had only been able to test approximately 400 samples a day, Korea, Italy and the UK are testing approximately 10,000 a day and China was able to conduct more than a million tests a week. The situation is changing in the US, however, including broadening the indication for coronavirus testing, offering state laboratories the freedom to create their own testing kits and an FDA promise of improved test kits to be soon available.
As a result of the recent changes in government policy and testing capability, we will be able to find a lot more of the ‘silent’ cases that had already been in the community but were not previously identified. The next few weeks will be crucial for the US to understand the true extent of Covid-19 spread in the country.