In addition to her clinical and academic commitments, she has been actively involved in the community response to HIV/AIDS in Malaysia. As convenor of the Malaysian Harm Reduction Working Group of the Malaysian AIDS Council, she led the advocacy for the implementation of harm reduction measures to tackle the problem of HIV amongst injecting drug users in Malaysia. She was President of the Malaysian AIDS Council from 2006 to 2010 and continues to serve as an Executive Committee member since stepping down as President. In this capacity, she has been involved in advocating for and overseeing the implementation of community-based HIV/AIDS programmes across the country. She remains as the Chairman of the Malaysian AIDS Foundation, a Trust whose role is to raise funds for HIV prevention, treatment and care programmes implemented by the Malaysian AIDS Council.
In 2008, she established the Centre of Excellence for Research in AIDS (CERiA) at the University of Malaya. Research activities undertaken at CERiA include clinical and basic science studies, epidemiological as well as socio-behavioural research focusing on the marginalised communities in Malaysia, particularly people who use drugs, prisoners, and men who have sex with men.
Dr Kamarulzaman has been a committee member of several regional and international organizations including TREAT Asia, the International Society of Infectious Diseases, and WAS a Co-Chair of the WHO Strategic and Technical Advisory Group on HIV. She was the Scientific Co-Chair of the XVIII International AIDS Conference in Vienna in 2010 and in 2013 was the local host for the 7th IAS Conference on HIV Pathogenesis, Treatment and Prevention in Kuala Lumpur. In April 2015 she was honoured with an Honorary Doctor of Laws from her alma mater, Monash University, for her outstanding achievements in medicine.