It is theoretically possible that people living with HIV with low CD4 cell counts might have a weaker immune response to vaccines. However, in practice this has not been documented for all vaccines and there is no evidence to support a less robust immune response to COVID-19 vaccines among people living with HIV and low CD4 cell counts. WHO is reviewing new evidence as it emerges and will provide updates. More importantly, advocacy is needed so that no one person is left behind and that national COVID-19 vaccination programmes do not exclude people from key and vulnerable populations, at risk of HIV, who may have limited access to health services. It is also important to advocate for the inclusion of people living with HIV, including those with more advanced disease, in COVID-19 vaccine trials to provide information to confirm efficacy.