In the late 1980s, she was the first dedicated HIV doctor at the Royal Free Hospital.
[1] In the late 1980s, Johnson was the first doctor in the Royal Free Hospital to specialise in HIV/AIDS.
[2] She developed a holistic care programme that could accommodate thousands of patients.
[3] In 2005, Johnson was named professor of medicine at University College London.
[6] She worked with Jane Anderson on creating the BHIVA guidelines on managing women with HIV.