Thomas is the founder of AIDS Care China, a well-known NGO that represents the rights and needs of people living with HIV/AIDS in China.
Founded in Guangzhou in 2001 as a counselling service for people living with HIV/AIDS, AIDS Care China now serves over 23,000 HIV positive people through its care centers located in hospitals and clinics in Guangdong, Sichuan, Yunnan, Guangxi and Hubei provinces. In 2006, the United Nations in China presented AIDS Care China with the inaugural Red Ribbon Award for the organisation's community-based approach in combating HIV/AIDS. Thomas was the recipient of the 2006 Keith D. Cylar International AIDS Activist Award from Housing Works.
In early 2015, AIDS Care China launched V-med, an online health and referral platform to improve public access to public health and medical services. V-med connects people to information, doctors and optimal testing and treatment services.