A man surnamed Zhang, 30, has been haunted by a mosquito bite on his head, which made his face swell up to a ball size, for two months, dahe.cn reported.

"I clearly remembered that I was bitten by a mosquito on May 26," Zhang said that he squeezed it with hand to relieve itching. However, the skin around the bump had festering symptoms then. Later, his whole face swelled up and his lips were swollen like sausages. He even couldn’t open eyes.

On June 15, Zhang’s body temperature went up to 39 degrees centigrade. Apart from a fever, Zhang did not have other symptoms. Zhang went to a hospital in Luoyang, Henan province on June 29.

In the following two months, he had been to hospitals in Jiangsu, Shanxi, Henan and Beijing. The doctors told him that he did not need any special treatment except cold compress on the bump and keeping calm.

Dai Tao, director of plastic surgery department of Luoyang Oriental Hospital said that he gave Zhang a series of physical examinations, and the results show that Zhang has no problem in heart and lung function. The facial swelling is purely caused by mosquito bites. Usually mosquito bite symptoms may occur up to 48 hours after the initial bite.

Why does a mosquito bite cause such a serious swelling? Dai Tao said swelling means that the immune system reacts to the chemicals in the bites.

Mr. Zhang was dismissed by his employer this July because he frequently asked for leave for medical treatment. Now he is resting at home.