219. A Randomized, Double-Masked, Placebo-Controlled Phase IIB Trial of Azithromycin and Trimethoprim-Sulfamethoxazole as Bacterial STI Prophylaxis in Pregnant Women with HIV

Background

This phase IIB randomized clinical trial was designed to test the efficacy of a novel regimen to prevent bacterial sexually transmitted infections and malaria in pregnant women with HIV in Cameroon, where HIV prevalence in pregnancy is 5.7%. Here we present the analysis of STI rates.

Methods

Pregnant women in prenatal care with confirmed HIV, gestational age < 28 weeks and singleton pregnancies were randomized to monthly azithromycin (AZ) 1 gram daily for 3 days and daily trimethoprim-sulfamethoxazole (TMPS) or the standard regimen of daily TMPS with monthly placebo AZ.

The main outcome of interest was the proportion of women with a composite STI measure: chlamydia, gonorrhea and/or incident syphilis at delivery. Nucleic acid amplification testing (NAAT) for CT/NG was performed on provider-collected vaginal swabs. Incident syphilis was defined serologically as a newly positive treponemal test or 4 fold increase in RPR/VDRL titer since baseline. The proportion was compared by relative risk with 95% confidence intervals and a significant p value set at < 0.05.

Results

A total of 308 women were enrolled at three hospital facilities between March 2018 and August 2020. In all, 155 women were randomized to the AZ/TMPS arm and 153 women to the TMPS arm. A total of 260 women (84%) had delivery samples collected. Both groups were similar with median age 32 years, maternal education (71% secondary school or university), HIV diagnosis 3 years prior, and 94% reported excellent adherence to antiretroviral therapy (ART). Median CD4 count was 473 cells/mm3 (IQR 326-663). At baseline, prevalence of chlamydia was 1.4%, gonorrhea 1.0% and syphilis 1.9%. There was no difference in the proportion of women with the composite STI measure (3.2% in the AZ/TMPS arm and 3.3% in the TMPS arm; RR 0.78 (95% CI 0.21 – 2.84); p=0.70). Adverse birth outcomes were lower in the AZ/TMPS arm, but not significantly (preterm delivery 5% vs 10.3% [p=0.1], low birthweight 2.8% vs 5.1% [p=0.34], composite adverse birth outcome 8.4% vs 13.1% [p=0.19]. Table 1:

COVID-19 vaccine acceptance and perceived risk among pregnant and non-pregnant adults in Cameroon, Africa

Background

The public health response to the global COVID-19 pandemic has varied widely by region. In Africa, uptake of effective COVID-19 vaccines has been limited by accessibility and vaccine hesitancy. The aim of this study was to compare perceptions of COVID-19 infection and vaccination between pregnant women and non-pregnant adults in four regions of Cameroon, located in Central Africa.

Methods

A cross-sectional survey study was conducted at urban and suburban hospital facilities in Cameroon. Participants were randomly selected from a convenience sample of adult pregnant and non-pregnant adults in outpatient clinical settings between June 1st and July 14th, 2021. A confidential survey was administered in person by trained research nurses after obtaining written informed consent. Participants were asked about self-reported sociodemographics, medical comorbidities, perceptions of COVID-19 infection, and vaccination. Descriptive statistics were used for survey responses and univariate and multivariable logistic regression models were created to explore factors associated with COVID-19 vaccine acceptability.

Results

Fewer than one-third of participants were interested in receiving the COVID-19 vaccine (31%, 257/835) and rates did not differ by pregnancy status. Overall, 43% of participants doubted vaccine efficacy, and 85% stated that the vaccine available in Africa was less effective than vaccine available in Europe. Factors independently associated with vaccine acceptability included having children (aOR = 1.5; p = 0.04) and higher education (aOR = 1.6 for secondary school vs primary/none; p = 0.03). Perceived risks of vaccination ranged from death (33%) to fetal harm (31%) to genetic changes (1%). Health care professionals were cited as the most trusted source for health information (82%, n = 681).

Conclusion

COVID-19 vaccine hesitancy and misinformation in Cameroon was highly prevalent among pregnant and non-pregnant adults in 2021 while vaccine was available but not recommended for use in pregnancy. Based on study findings, consistent public health messaging from medical professionals about vaccine safety and efficacy and local production of vaccine are likely to improve acceptability.