An English teacher at a private school in China’s Inner Mongolia region was forced to make a public apology after having bought a fake tuberculosis diagnosis online, just so he could take a longer vacation for China’s National Day.

The teacher, identified only as Mr. Du, reportedly paid 470 yuan ($67) for a fake chest scan and doctor’s diagnosis on the internet, both of which showed that he was suffering from tuberculosis, a serious and highly contagious pulmonary disease. He then presented the documents to his employers, hoping it would convince them to approve a lengthier medical leave, allowing him to prolong his China’s National Day vacation. Only he never considered how serious his fake diagnosis actually was.

Because tuberculosis (TB) is so contagious and potentially life-threatening, Mr. Du’s school in Hohhot, the capital of Inner Mongolia, was forced to pay for the medical check-ups of all of the English teacher’s students, to make sure they hadn’t contacted the disease as well. As luck, or rather bad luck, would have it, two of the students tested positive for tuberculosis.

Shocked by the news that some of his students were suffering from TB, Mr. Du again went online and paid another 315 yuan ($45) for another fake diagnosis, which showed that he no longer had the disease. Only parents didn’t believe him this time around, as the condition requires months of antibiotics treatment to cure, and forced him to undergo a third testing at a Hohhot hospital. This showed both that Du had never suffered from tuberculosis – which leaves physical marks on the lungs – and that the previous X-rays belonged to another person entirely.

Caught with the lie, Mr. Du, who parents say is very popular with students at the unnamed private school, admitted that he had tried to deceive his employees in order to prolong his vacation. Afraid of being caught when the two students were actually diagnosed with TB, he lied again to cover it up. Only that just made people even more suspicious.

The English teacher admitted that he did not know how serious tuberculosis was when he chose it as a fake diagnosis. It’s unclear whether he was allowed to keep his job, especially after the story went viral on Chinese social media.