The number of confirmed cases of the new coronavirus in China has skyrocketed to more than 9,000, surpassing the official count during the SARS epidemic. But the true number of infections may be even higher, as health workers struggle to catch up with the disease.

A shortage of testing kits and overworked hospital staff are straining China’s health system, hampering efforts to accurately track how many people have the pathogen. The result is a hectic and imprecise process that’s creating bottlenecks as health experts attempt to pin down the scope of a disease that has claimed more than 200 lives.

The challenge of keeping up with the tally can be seen in Hubei, at the center of the outbreak.

The province can process about 6,000 tests a day, health commission director Liu Yingzi told a press briefing Wednesday, noting that Hubei had about 50,000 test kits in stock. But with 5,806 confirmed cases and 32,340 people under observation, it’s uncertain if that is enough.

Getting a handle on the numbers is becoming more urgent as the outbreak spreads beyond China’s borders, prompting the World Health Organization to declare a global health emergency. Neil Ferguson, a public health expert at Imperial College London, said his “best guess” was that 100,000 people could be infected around the world, according a Jan. 26 report in the Guardian.

Complicating the situation is the elusive nature of the disease and how it is transmitted, as well as the difficulty in diagnosing it. Evidence has emerged that the disease can be passed by people before they show symptoms, or who may show no symptoms at all.

Jonathan Yu, a doctor at a university hospital in Wuhan, is on the front lines, testing patients for the coronavirus. Accurately spotting the virus isn’t easy and can take several attempts, he said.

“A patient may be found as negative for the first or second test, and then found to be positive the third time,” said Yu. “It is like fishing in a pond: You did not catch a fish once, but that does not mean the pond does not have fish.”

Another doctor in the city who declined to be identified said her hospital was facing shortages of testing kits to confirm that people have the disease, as well as lacking in spare beds and respirators for patients.

Chinese human rights lawyer Chen Qiushi said in a video posted on social media Jan. 29 that some hospitals in the city of Wuhan don’t have enough kits and are telling patients that severe cases have to be prioritized. Chen, who has expressed anti-Communist Party sentiments in the past, cited interviews with people who suspected they have the virus as well as visits to local hospitals.

There were 9,692 confirmed cases in China as of Thursday, according to the National Health Commission. That’s a whopping 3,000% increase from a few hundred patients just 10 days ago.

Part of that may reflect increased efforts to test for the disease, which means it’s being found in more and more places. Still, a lack of sufficient testing kits to confirm whether people have caught the virus is likely to mean there are more people sick than the figures show.

The spike in cases could continue after the Lunar New Year holidays. The incubation period for the coronavirus can be up to 14 days, so the impact of hundreds of millions of people traveling in China during the holidays may show up by mid-February. Zhong Nanshan, a respiratory disease expert who led the research into a treatment for SARS, told local media this week he expects the number of confirmed cases to peak within 10 days.

Wu Zunyou, chief epidemiologist at China Center for Disease Control And Prevention, downplayed the severity of the epidemic, saying the surge in the number of confirmed cases in Hubei in the past three days does not necessarily mean the situation there has deteriorated significantly.

In an interview with China’s state TV Thursday, Wu said the latest jump was a result of a lack of medical resources in the early stage of the outbreak in the city. Many of the patients diagnosed with the disease in the last few days actually fell ill days before the lockdown of the city, but many of them could not be diagnosed and reported in time.

“Don’t be scared by the numbers in the past three days,” Wu said. “The (real) statistics are far more promising.”

New Kits

China is making moves to improve the situation. Health officials approved two new kits on Tuesday, in addition to the existing four types, according to Xinhua News Agency. One of the two new kits can give results in about 30 minutes, shortening the time needed to diagnose cases, according to Technology Daily.

Roche Holding AG is also producing kits, and the government says it’s streamlining transport access to make sure relevant supplies get through. However, Roche said Thursday it was still having trouble getting its equipment to where it’s needed.

Yu, the Wuhan doctor, said the shortage of virus detection kits has lessened recently, although there is still a shortage of masks, glasses and other supplies.

Because the incubation period for the virus is so long, Yu has been sleeping and working at the hospital, afraid to go home to his family.

“I have not gone home for more than a week,” he said.