‘let the Evidence Speak for Itself’

At hospitals designated to treat patients with Covid-19, Zhang made daily rounds of more than 300 confirmed cases, attempting to decipher the highly contagious virus that had swept China. On February 28, NewsChina secured an exclusive interview with Zhang to discuss the state of China’s disease control measures as well as the challenges ahead.　

NewsChina: China seems to be emerging from the Covid-19 outbreak, but conditions are worsening overseas. What challenges lie ahead?　

Zhang Wenhong: When Wuhan was under strict lockdown, there were three scenarios for China: Win, which meant bringing the epidemic under control in two to four months, hold, which meant controlling the epidemic in six months, or fail, which meant a pandemic. When the H1N1 broke out in the US in 2009, stringent anti-epidemic measures were adopted but the disease was out of control.　

We predicted that if the epidemic were successfully controlled in China, the world would be safer. However, now there are more new cases reported overseas than in China, and I’m really worried about that. China was the epicenter of the virus and many countries did not allow Chinese people to enter, but the situation has reversed now. Handling the influx from abroad poses a big challenge for Chinese policymakers.　

NC: We have still not located patient zero. Does that mean Covid-19 may not have originated in China?　

ZWH: This is a very sensitive question and I insist on letting the evidence speak for itself. There are two very important things. Where the virus appeared first and where it is in its evolution.　

When the first case was reported in Shanghai, we tested the gene sequence of the virus strains and found that the virus was from Wuhan. The medical world has been searching for patient zero ever since. Through whole genome sequencing analysis, we discovered that SARS-CoV-2 (the coronavirus that causes Covid-19) originated in bats, and has a similar clinical manifestation with SARS (Severe Acute Respiratory Syndrome).　

But since there’s clear evidence that SARS-CoV-2 came from bats, it doesn’t matter whether the virus came from bats at Huanan Seafood Market in Wuhan or from a market in a neighboring county. As for patient zero, I won’t take anybody or any institution at their word. I only trust evidence.　

NC: Many have characterized the novel coronavirus as elusive and tricky. Is three months enough time to study a new contagious disease like Covid-19?　

ZWH: The Covid-19 pathogen belongs to the coronavirus family but it has unique characteristics. Who could guarantee that it takes two weeks for the human body to expel the virus? We’ re still probably unaware of all its features.　

Covid-19 is actually not as fatal as SARS. The World Health Organization said its R0 (basic reproduction number) is between 2.0 and 2.5, which means Covid-19 is more contagious. A person infected with SARS would develop a high fever and go into critical condition. But there are many mild cases of Covid-19, which makes it difficult to detect. That’s why it has spread so rapidly.　

According to official data, transmission among family members accounted for 70 percent of total cases, and close contact transmission is a major characteristic of Covid-19. It has features of SARS and the flu. It’s not a simple pneumonia, because many patients do not show pneumonia-like symptoms. In some critical patients, the virus severely damages the heart and other organs.　

NC: Is the virus becoming less scary as our understanding of it deepens? 　

ZWH: The public feared the virus because they knew little about it. As of today [February 20], 279 patients have been discharged from hospitals in Shanghai. The city had its first case confirmed on January 20 and to date 83 percent of patients have been discharged. From this perspective, the disease is curable, wouldn’t you agree?　

When the first case appeared in Shanghai, The Lancet ranked the city as the most at-risk because it saw the most airline travelers in China. The journal estimated that if no control measures were taken, 800,000 people in Shanghai were at risk of infection. Right now, there are only 200 imported cases confirmed in Shanghai. We have studied every patient and found that they either came from Wuhan or had close contact with people from Wuhan. For a city of 30 million and so many suspected cases, the best outcome we could hope for was 80,000 cases, according to a mathematical model. Today, however, Shanghai only has 337 cases.　

So looking back, would people still think the possibility of prevention and treatment is still laughable? No. As long as the country and the public stick together and make the anti-epidemic campaign a top priority, it can be controlled and cured. It’s hard to say whether China’s response is suited to Singapore or Japan, or whether their measures would suit China. The most basic parts of containing contagious disease, however, are the same, such as how to control infection sources, how to cut off modes of transmission, and how to protect vulnerable groups. Each country has to take prevention measures suited to their own conditions.　

NC: When do you think vaccines will be produced and what roles would they play?　

ZWH: Many are working on vaccines and it is difficult to say when they would hit the market. The SARS epidemic ended, and there are no vaccines to this day. MERS still exists in Middle Eastern countries and there are still no vaccines for it. Even if everything goes well, the earliest vaccine rollout would be by year’s end.　

I want to make something clear: A viable vaccine does not mean the epidemic is over. For example, while there are several vaccines and medicines for the flu, the disease is still prevalent. Vaccines are important, but would come too late for China to use as epidemic controls. Nevertheless, they could help other countries. We cannot pin all our hopes on vaccines to control the coronavirus.　

NC: China has been on its highest level of alert for more than one month, and some provinces have since lowered their alert levels. When will Shanghai do the same?　

ZWH: Shanghai received an influx of 15 million to 20 million people after Chinese New Year, so I believe Shanghai can’t decide for itself when it should reduce its emergency response level. Megacities like Beijing and Shanghai have to work jointly with the central government. As political and financial centers, they have different considerations than provincial cities. For example, checks at fever clinics in Shanghai are stricter than ever before.　

But it’s also not necessarily a good thing to see no new cases in Shanghai. It actually worries me. So many people arrive in Shanghai every day, how could the number still be zero? If we found one or several cases, and I mean imported cases, I’d feel relieved. The more imported cases we discover, the safer our city becomes. Many provinces have reduced their response levels, but we should remain vigilant. When everyone has returned to Shanghai and resumed their work, and no new cases are reported, only then should we take off our masks.　

NC: How can we strike a balance between the strict anti-epidemic measures in China with the more passive measures in Singapore?　

ZWH: Singapore raised its response level to orange, the second-highest level, but the government did not require all residents to wear masks or restrict community activities. Singapore reserved the use of N95 masks for medical workers. Critical patients are treated at hospitals while mild cases are quarantined at home. It seems like Singapore isn’t actively combating the epidemic, but that’s not true. 　

Singapore started its epidemic controls on January 2, the day China’s expert medical team arrived in Wuhan. Singapore then restricted flights from China and did not issue visas to travelers from Wuhan. To date, there have been more than 100 cases in Singapore [455 cases, 2 deaths in Singapore by March 23], but only dozens of imported cases, a feat for such a big city.　

Singapore requires new arrivals to stay at home for a 14-day quarantine. There are 110 fever clinics in Shanghai and 76 in Beijing, but Singapore has 800. When the epidemic broke out, Singapore launched a community system to better receive patients with fevers. China took the right measures to combat its epidemic, but Singapore’s measures have also been successful. 　

NC: Huashan Hospital’s infectious diseases department is one of the best in China. What has been the department’s role in preventing the epidemic?　

ZWH: The coronavirus outbreak has exposed many problems in China’s health system. Experts identified the Covid-19 pathogen in just a week, but there were many warning signs in the days prior and we could have done it much earlier. Over the years, the infectious diseases department at Huashan Hospital has had only one job: to remain on high alert for new contagious diseases.　

When the first case of H7N9 was detected in Shanghai several years ago, our department quickly sequenced the virus and reported its findings to central health authorities. I think detection and prevention systems are very important, because once an epidemic occurs, it’s already too late. China’s response was fast but the virus transmits even faster. Medical institutions had to take action before the outbreak. China should invest more in infectious disease departments, particularly at local hospitals, to keep our country and people safe.