It took Zhang Hongwen nine days and three swab samples to get her mother hospitalized. Nine days spent in waiting rooms amid a crowd of coughing patients and their relatives. Up to 60 people were crammed into a waiting room the size of a classroom.

"Everybody was using the same toilet. I thought about how easy it was to get infected," she said. "I felt helpless and terrified but I had no choice. Once my mother had gotten ill, I had to take care of her."

Zhang (not her real name) is living in Wuhan, the epicenter of the coronavirus epidemic. DW spoke to her on the phone. Her mother, a woman in her late seventies, came down with fever and cough at the end of January, a few days after a Chinese New Year's Eve spent with relatives.

"There were young people and children around, maybe she caught it there," Zhang said.

Some of the relatives later reported flu-like symptoms but none of them got tested for the new coronavirus. Her mother's symptoms quickly grew more severe. She took her to the hospital where her lungs were screened, blood sampled and nose swabs were taken.

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The computer tomography revealed the typical hazy areas on the lung and her blood also showed signs of the infection. But the test for the virus turned out negative. They were sent home.

"We were told that without a positive test, she would not be admitted to hospital," Zhang said.

Sudden surge in cases

Wuhan, where the virus was first detected, continues to be the place that has been hit the hardest by the disease. The city and the surrounding province of Hubei have registered 80% of all cases and 95% of all deaths so far. On Thursday, the province reported a sudden surge in numbers. In one night, almost 15,000 new infections were added to the count.

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The total number in the province jumped from 33,366 to 48,206 patients. The surge is due to an adjustment in the counting of cases. Previously, only cases that had a confirmed laboratory test would be included in the statistics. Now cases that are diagnosed based on symptoms but without a positive test result, are also being counted as infections.

Many of these cases are of people who could not be tested due to a shortage of resources. But there are also other cases like those of Zhang's mother, who could not be treated because of a faulty test result.

It is hard to estimate how common these cases are. In the past few days, a number of Wuhan residents have posted similar stories on social media about relatives being unable to get access to treatment in hospitals.

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DW has contacted several of them. While declining to go on record, some confirmed that they had had similar experiences. One woman said that she had finally managed to get her mother into a hospital and herself into a designated quarantine facility after days of trying. Another man told us that after several days spent waiting in hospitals, he and his elderly mother were sent home with a negative virus test result.

There is no clear data to describe the accuracy of the tests. Benjamin Cowling, epidemiology professor at Hong Kong University, said that there might be two main sources for inaccurate test results.

The samples, swabs from the nose or throat, might not have been taken accurately and therefore not contain a sufficient number of traces of the virus. Another possibility would be bad testing kits and bad work at the laboratories, something that he thinks is rather improbable.

"We presume the accuracy of the tests is high," said Cowling. "But it is never 100%."

For the hospital, however, the case of Zhang's mother was clear.

"The doctor said the symptoms left him with no doubt that she was infected," she recalled. "But without the positive test result, we were not eligible for a hospital bed."

Zhang Hongwen suspected that the severe admission criteria were meant to keep the numbers down but she had no other option than to comply.

Nine days in waiting rooms

Her mother's condition left her with little choice than to try again, Zhang said. The old woman was barely able to get up. So she took her to the hospital again. There she again underwent another test and the result was again negative.

Zhang and her mother spent nine consecutive days in the waiting rooms of hospitals. When they came home, she thoroughly tried to disinfect her house, moving around every item that her mother might have come into contact with.

"Everything is upside down at home now," Zhang said.

Finally, on day nine, a third test brought the positive result she was waiting for. Her mother got admitted - just two days prior to the sudden change of criteria.

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A tired Zhang Hongwen returned home after admitting her mother. In the meantime, she has also started coughing but is so far without fever. She has taken a home test and has quarantined herself at home waiting for the result. Now that the test is not as important as before, she plans to stay at home unless she develops more severe symptoms.

"If I develop a fever I will try to get admitted," she said.