Besides providing assistance in his daily life, his Chinese colleagues took him on memorable trips to places where he could soak up Chinese culture and the scenery.

One such experience was in Guilin, where Khan and his colleagues rafted along the Lijiang River on a cool moonlit evening.

Khan also enjoys playing table tennis and badminton with his friends in Nanning.

Over the years, Khan has attempted to learn some Chinese and as a result can now get by in his daily life.

"The local people are very friendly. Meanwhile, more and more young people are able to speak English, which has made my life here easier."

Other than working on projects and attending seminars in China, Khan trains researchers and students at Guangxi Institute of Veterinary Research. Thanks to him, the institute has reached a long-term cooperative agreement with the University of Connecticut.

In 2013 Khan won the Friendship Award, the top honor given by the central government to foreigners who contribute substantially to China's development in various fields.

He is glad to have been recognized for his work in China, he says.

He and his colleagues at the Guangxi Institute of Veterinary Research are now working on developing a new kind of avian-influenza vaccine based on nano particles that would target bird flu viruses. The vaccine is expected to be applicable both for humans and animals, he says.

"These are huge public health issues, which is why the study is important," he says of the project, which includes studying diseases such as SARS.

Khan suggests China needs to tackle public health issues more effectively, including carrying out detailed policies to control the quality of food products and the use of antibiotics for animals.

"These areas are basic and should be emphasized. We should think 20 or 30 years ahead, and now is the time to do it."