Over the last two weeks of May, all residents over the age of 5 in Wuhan, China were tested for the presence of active SARS-CoV-2 virus replication. The tests identified 300 people with active infection. None of those tested show any signs of infection. All family members and close contacts of the 300 were also tested. None were found infected. The surfaces of the living spaces of those infected were also swabbed and tested. No viral nucleic acid was found on any of the nearby surfaces or doorknobs. Wuhan officials believe this to be evidence that those who tested positive weren’t highly infectious. Since the testing spree ended, no new Covid cases have been identified in Wuhan or in the entire province of Hubei.
The mass testing initiative followed a small and isolated outbreak of new infections in the city, more than a month after the stay at home order was lifted in mid-April. The mass screening program was focused on breaking the chains of transmission and reassuring residents that the city was safe.
At the peak of the testing campaign, one million people a day were tested. Testing stations were set up around the city. To speed up the testing process, samples were pooled and tested for up to five people. If one of those samples was found to be positive, all five were tested individually. Throat rather than nasal swabs were used for sample collection.
Before the campaign began, residents were notified that it was their civic duty to take part in the program to protect themselves, their family, and their city. Signs posted around neighborhoods reminded residents that “A nucleic acid test is your responsibility to yourself, your family and society.” Yet, whether residents agreed it was their civic duty or not, participation was mandatory. According to reports, one official announcement read “You will receive a text from local health officials, along with your national ID, you will get tested. If you test negative, you will receive this ‘health code’, and only then you can return to work,” he said.
The health code refers to a color-coded system that people must display on their mobile phones, when asked to. Green is for those who are clear, yellow for those exposed, and red for virus-positive. If you were color-coded yellow, you could change from yellow to green, following a period of controlled quarantine. Or from red to green following recovery and a mandatory period of isolation under quarantine. A green, all clear, personal identification code is required for entry in public spaces.
All the residents of a second city, Mundanjiang, are also being tested for active infection. This follows the discovery on June 3 that 15 people in the city were actively infected. Mudanjiang lies near the border of both Russia and South Korea. The infection may have entered the city from residents retuning overland from Russia. All of the 2.5 million residents over the age of five will be tested over the next six days.
China’s efforts to contain Covid-19 are truly impressive. Once the disease was known to be easily transmissible among people and deadly consequence of infection understood, China put in place highly effective public health measures that reduced the number of new cases per day from the thousands in February, to hundreds in March, to below fifty in April, and to low single digits for the entire country in May. All this without a vaccine or drug to stop the spread of the virus.
But what are we doing today in America to stop the epidemic? Practically nothing compared to what China has achieved. The Centers for Disease Control and Treatment used to share their count of the number of viral tests administered nationwide. In mid-May, they stopped that practice and started bundling viral tests—which test for active infection—with antibody tests, which can show a person has been previously infected. At the time, the number of viral tests administered since the start of the outbreak was at roughly 10 million. Less than what one city in China managed to do within two weeks.
Now that the CDC is no longer sharing viral testing numbers publicly, it is impossible for us to know if we are increasing our testing enough to make a difference. What we do know is that we can make a difference.
The take-home message from Wuhan’s testing spree is simple: The epidemic can be stopped in its tracks with the public health measures we already have in hand. Governments that fail to implement these measures fail in their primary duty to protect the people of their nation.