Protecting Against HIV Vaccine Misinformation With Adolescent Girls and Young Women in South Africa (PROTECT)

Adolescent girls and young women (AGYW) between the ages of 15-29 years continue to bear the brunt of Human Immunodeficiency Virus (HIV) infections in South Africa despite progress recorded in prevention and treatment programmes. The ongoing susceptibility of young women to HIV infection and the sub-optimal uptake of prevention options such as Pre-Exposure Prophylaxis (PrEP) that are highly effective creates a need for an HIV vaccine to benefit populations at substantial risk of HIV infection. However, lessons from previous vaccine studies and the recent COVID-19 vaccine have highlighted significant barriers to vaccine uptake, such as widespread misinformation and vaccine hesitancy. These challenges threaten the successful implementation of a future HIV vaccine. Building on these insights, this study will utilise psychological inoculation theory to develop and evaluate HIV vaccine messages among adolescent girls and young women. Primary objective: To compare changes in intentions to receive HIV vaccine following misinformation exposure in groups with and without psychological inoculation and behavioural economics boost.

Secondary objectives: (1) To compare believability and persuasiveness of misinformation claims and motivational threat associated with misinformation in groups with and without psychological inoculation and behavioural economics boost. (2) To explore subgroup effects by relevant sociodemographic and behavioural factors including HIV risk, PrEP history, COVID-19 vaccine history, general vaccine hesitancy, and information avoidance. The investigators will conduct a two-arm randomized controlled trial of 2-3 inoculation messages that address emerging myths and misinformation about the HIV vaccine in South Africa. Participants will be randomly assigned to a control group or an intervention arm: enhanced inoculation message with insights from behavioural economics.

Study Overview

• Status: Active, not recruiting
• Conditions: HIV Vaccine; Misinformation
• Intervention / Treatment: Behavioral: Nutrition information; Behavioral: Enhanced inoculation message

• Study Type: Interventional
• Enrollment (Actual): 2163
• Phase: Not Applicable

Contacts and Locations

Study Locations

• South Africa
  • Johannesburg, South Africa
    • Health Economics and Epidemiology Research Office, University of the Witwatersrand

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Female
• Age 18-29 years
• Self-reported history of sexual activity in the past 12 months
• Self-reported HIV-negative status or unknown HIV status at enrolment
• Willing and able to provide written informed consent
• Able to read and understand English

Exclusion Criteria:

• Unwilling or unable to provide consent for study participation.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control; Participants enrolled in the control group will receive unrelated information on diabetes and nutrition topics of the same length as the inoculation messages. Please see Appendix 6 for an example of how this message will be structured. This will make the control group an attention control group and ensure that findings are not confounded by the intervention group spending more time and attentional resources on participation in the study.	Behavioral: Nutrition information; Participants enrolled in the control group will receive unrelated information on diabetes and nutrition topics of the same length as the inoculation messages. Please see Appendix 6 for an example of how this message will be structured. This will make the control group an attention control group and ensure that findings are not confounded by the intervention group spending more time and attentional resources on participation in the study.
Other: Enhanced inoculation message; Participants enrolled in the enhanced inoculation message arm will receive messages that warn them about impending HIV vaccine misinformation and explains why those claims are false or misleading, the messages will be enhanced with insights from behavioural economics see Appendix 5: "Inoculation message with a BE boost" for an example of the inoculation message. As part of the behavioural economics boost, participants may choose to receive a small token (e.g., sticker, badge, bracelet) with a message promoting vaccination as a consistency and commitment prime.	Behavioral: Enhanced inoculation message; Participants enrolled in the enhanced inoculation message arm will receive messages that warn them about impending HIV vaccine misinformation and explains why those claims are false or misleading, the messages will be enhanced with insights from behavioural economics see Appendix 5: "Inoculation message with a BE boost" for an example of the inoculation message. As part of the behavioural economics boost, participants may choose to receive a small token (e.g., sticker, badge, bracelet) with a message promoting vaccination as a consistency and commitment prime.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
HIV vaccine intention, at the end of the baseline assessment	Intention to get the HIV vaccine, measured after inoculation intervention and misinformation exposure The intention to get the vaccine will be measured on a 0-10 scale.	At the end of the baseline assessment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
HIV vaccine intention, follow-up	Intention to get the HIV vaccine, measured at follow-up survey following misinformation exposure and intervention. Measured on a 0-10 scale.	2-4 weeks
Recommend to friends, at the end of the baseline assessment	Intention to recommend the HIV vaccine to friends, measured at survey baseline following misinformation exposure and intervention. Measured on a 0-10 scale.	At the end of the baseline assessment
Recommend to friends, follow-up	Intention to recommend the HIV vaccine to friends, measured at follow-up survey following misinformation exposure and intervention, controlling for baseline pre-intervention/exposure intention. Measured on a 0-10 scale.	2-4 weeks
Credibility of inoculated exposure #1	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Credibility of inoculated exposure #2	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Credibility of inoculated exposure #3	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Credibility of inoculated exposure #4	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Credibility of inoculated exposure #5	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Credibility of inoculated exposure #6	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Anxiousness of inoculated exposure #1	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Anxiousness of inoculated exposure #2	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Anxiousness of inoculated exposure #3	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Anxiousness of inoculated exposure #4	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Anxiousness of inoculated exposure #5	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Anxiousness of inoculated exposure #6	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Shareability of inoculated exposure #1	Likelihood of your sharing the claim for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Shareability of inoculated exposure #2	Likelihood of your sharing the claim for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Shareability of inoculated exposure #3	Likelihood of your sharing the claim for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Shareability of inoculated exposure #4	Likelihood of your sharing the claim for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Shareability of inoculated exposure #5	Likelihood of your sharing the claim for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Shareability of inoculated exposure #6	Likelihood of your sharing the claim for both HIV vaccine claims specifically inoculated against and four new claims. All measured on a 1-7 scale	At the end of the baseline assessment
Credibility of inoculated exposure #1, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Measured at follow-up on a 1-7 scale	2-4 weeks
Credibility of inoculated exposure #2, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Measured at follow-up on a 1-7 scale	2-4 weeks
Shareability of inoculated exposure #1, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Measured at follow-up on a 1-7 scale	2-4 weeks
Shareability of inoculated exposure #2, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Measured at follow-up on a 1-7 scale	2-4 weeks
Anxiousness of inoculatedexposure #1, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Measured at follow-up on a 1-7 scale	2-4 weeks
Anxiousness of inoculated exposure #2, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Measured at follow-up on a 1-7 scale	2-4 weeks
Credibility of new claims, exposure #7, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Credibility of new claims, exposure #8, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Credibility of new claims, exposure #9, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Credibility of new claims, exposure #10, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Credibility of new claims, exposure #11, follow-up	Extent to which the claim is credible, extent to which the claim makes you anxious or nervous about the HIV vaccine, likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Anxiousness o of new claims, exposure #7, follow-up	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Anxiousness of new claims, claim #8, follow-up	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Anxiousness of new claims, exposure #9, follow-up	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Anxiousness of new claims, exposure #10, follow-up	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Anxiousness of new claims, exposure #11, follow-up	Extent to which the claim makes you anxious or nervous about the HIV vaccine for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Shareability of new claims, exposure #7, follow-up	Likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Shareability of new claims, exposure #8, follow-up	Likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Shareability of new claims, exposure #9, follow-up	Likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Shareability of new claims, exposure #10, follow-up	Likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks
Shareability of new claims, exposure #11, follow-up	Likelihood of your sharing the claim, for both HIV vaccine claims specifically inoculated against at baseline. Each measured at follow-up on a 1-7 scale for each of 5 claims, and then summed for a global index (range: 5-35).	2-4 weeks

Collaborators and Investigators

• Sponsor: University of Pennsylvania
• Collaborators: Boston University; National Institute of Mental Health (NIMH); University of Cape Town; Health Economics and Epidemiology Research Office, University of the Witwatersrand

Study record dates

Study Major Dates

• Study Start (Actual): July 24, 2025
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: November 7, 2024
• First Submitted That Met QC Criteria: November 18, 2024
• First Posted (Actual): November 22, 2024

Study Record Updates

• Last Update Posted (Actual): April 2, 2026
• Last Update Submitted That Met QC Criteria: April 1, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: HIV; South Africa; Adolescent Girls and Young Women; Prevention: Vaccines
• Additional Relevant MeSH Terms: Behavior; Communication
• Other Study ID Numbers: 1R01MH132401 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: The investigators are still determining the data sharing plan and if we will be sharing IPD yet

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No