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<div><p>Background</p><p>Human Papilloma Virus (HPV) vaccination can prevent more than 90% of cancers caused by HPV. Although this vaccination is recommended and provided at no cost to all adolescent girls aged 9 to19 years in Uganda, its uptake remains low. We sought to determine the uptake of, and factors associated with HPV vaccination among adolescent girls living with HIV in Uganda.</p><p>Methods</p><p>We conducted an explanatory sequential mixed methods study, among adolescent girls living with HIV, attending HIV care at the Mulago ISS HIV clinic in Kampala, Uganda. We administered a structured questionnaire to elicit data on HPV vaccination and its covariates to a systematic random sample of 264 adolescent girls with HIV. A participant who had received all the three recommended HPV vaccine doses was classified as fully vaccinated. We then conducted four focus group discussions among adolescent girls living with HIV (n = 32), eight in-depth interviews among their parents and five Key informant interviews among their healthcare providers. We conducted descriptive statistics and logistic regression analyses for the quantitative data before thematic analysis for the qualitative data.</p><p>Result</p><p>Of 264 adolescent girls, 31% (83/264) had at least one HPV vaccine dose; 22% (59/264) two doses, while 8.0% (21/264) were fully vaccinated (received three doses). While most participants received their first and second doses (48% (40/83)) and 57.6% (34/59), respectively) from school, the largest number of participants (47.1% (12/21)) received their third dose at community outreaches. Participants who received counseling from community members were three times more likely to get fully vaccinated compared to those who did not receive counseling (aOR 3.28, Cl:1.07–10.08, P = 0.038). From the qualitative follow-up, three major themes were identified: (1): Limited information about HPV vaccination, which gave room for misconceptions and doubts about the vaccine; (2) Parental influence on adolescent decisions was strong despite parents having limited knowledge about HPV vaccination and (3) Inadequacy of HPV vaccination services at the hospital and in the schools.</p><p>Conclusion</p><p>Full HPV vaccination was low among adolescent girls living with HIV. Counseling of the adolescents by community members, alongside HPV vaccination community outreaches, provided a platform for vaccination. There should be strategies to provide adequate information about HPV vaccine to health workers, parents, and the adolescents. In addition to schools, community-based initiatives, including outreaches and lay-health workers can be utilized to improve HPV vaccine uptake among girls with HIV.</p></div>