Yiwu deploys digital systems to strengthen infectious disease surveillance

A doctor at Yiwu Central Hospital in Zhejiang province sits down at her computer. A fever patient has just left the clinic. Instead of reaching for a pen and a paper form—the old way, which took time and often produced illegible scrawls that had to be deciphered later—she opens a digital system. A few clicks. Some fields to fill. Within moments, the case report travels to disease control agencies for verification and handling. What once required manual paperwork and phone calls now happens in seconds.

This shift from handwritten cards to digital submission represents something larger than convenience. Wang Binlu, a public health worker at the hospital, describes the old system plainly: it was slow and error-prone. Illegible handwriting created gaps in the data. The new approach eliminates those friction points. The same digital logic extends to another critical step—when samples test positive, they can now be submitted to advanced laboratories for retesting through the same streamlined pathway. Speed and accuracy, once competing demands in public health, now move together.

Yiwu is not a typical city. It sits at the center of global trade, home to the world's largest wholesale market for small manufactured goods. People arrive from everywhere—buyers, sellers, traders, workers. The registered household population is roughly 900,000, but the actual number of people living there at any given moment is far larger: about 3.4 million. That gap between official residents and actual inhabitants reflects the constant flow of migrant workers and foreign businessmen passing through. Jiang Jun, director of Yiwu's disease control and prevention center, frames the challenge this way: in a city where the population can triple depending on the season and the business cycle, detecting disease early is not optional.

Yet despite the volume of inbound travelers in recent years, Yiwu has avoided major local transmission of infectious diseases triggered by imported cases. This is not luck. It is the result of systems designed to catch problems before they spread. All nine secondary or higher-level hospitals across the city and fourteen community healthcare centers now run national early warning software that replaces the manual reporting process entirely. Instead of waiting for doctors to submit forms, the system pulls in syndromic data—fever, cough, other symptoms—along with information from schools and elderly care homes. It analyzes these streams continuously, looking for patterns that might signal an outbreak before it becomes obvious.

Zhu Liebo, deputy director of the disease control center, reports that through July of this year, the city handled 344 emerging incidents using this surveillance approach. Each one was caught early enough to intervene before it could spread. The summer brought conditions that typically favor mosquito-borne diseases: high temperature, humidity, heavy rainfall. Yet Yiwu reported no local transmission of dengue fever or chikungunya fever from imported cases. The hospitals are equipped to test for both diseases. Epidemiological investigation data moves electronically alongside samples to the CDC and testing facilities through an online coordination system. The confirmed diagnosis rate for mosquito-borne diseases at the initial consultation has reached 97.3 percent, up more than ten percentage points from the previous year. Response teams activate and deploy within thirty minutes.

This is not the end of the story but a waypoint. The national government, through its 15th Five-Year Plan for disease control released in July, has signaled that the work will deepen. The plan calls for upgrading monitoring and emergency command platforms at the national and provincial levels, improving big data integration and management, and unifying information systems while strengthening their connectivity. Yiwu's experience—a city that has learned to see disease patterns in real time across millions of people—will likely inform how that larger infrastructure develops. The question now is not whether digital surveillance works, but how far it can reach and how quickly the entire system can respond when it detects something new.