Every summer, Mazhar Khan goes to Nanning, capital of the Guangxi Zhuang autonomous region in Southwest China, to spend a month or two.

And each time, the professor of pathology at the University of Connecticut is welcomed with a big reception in Nanning, which he says is like his second home.

Khan, 66, is a US citizen of Pakistani origin, and he was in Beijing on Sept 3 to witness the grand military parade marking the 70th anniversary of the end of World War II.

"It was a great honor for me to be invited to the celebrations," Khan tells China Daily. "It reminds me of how China has progressed in the past years."

Khan, who holds a PhD in veterinary medicine, applied molecular biology to diagnose diseases in birds related to mycoplasma and salmonella bacteria.

Along with other researchers, he developed a DNA-test kit for mycoplasma in chickens, which is often used in the United States.

Khan first came to China in 1998 as a visiting scholar at the Guangxi Institute of Veterinary Research, where he collaborated with in-house biologists on a project on the prevention of major communicable diseases including bird flu. That partnership encouraged both sides to continue working together on similar projects.

In the past two decades China has rapidly changed, he says, apparent from the economy and the number of airports, highways and general urban expansion.

But society in China has changed, too, he says. Chinese have become more conscious about protecting the environment and have become more confident in themselves.

In addition, Chinese are increasingly getting international exposure.

Khan used to be among the very few foreigners in Nanning in the '90s. Without much knowledge of Chinese and with his family back in the US, his stay in China was lonely.

"But I received great help from my Chinese colleagues," he says.

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."