Karunaweera is a Medical Parasitologist and is an expert, particularly in the fields of malaria and leishmaniasis.

She is an authority in scientific research that encompasses wide ranging fields including pathogenesis, immunity, molecular and epidemiology.

She is responsible for pioneering work in the field of leishmaniasis in Sri Lanka and established its first diagnostic and research laboratory in the country.

She is the Founder President of the National Chapter of Organization for Women in Science for the Developing World that leads career development programs for young scientists, especially women.

She serves on many national and international scientific, consultative and editorial boards sharing her expertise in an honorary capacity.