Knowledge of HIV prevention biomedical tools among African immigrants in France: the Makasi project

Background

In France, post-exposure prophylaxis (PEP) and pre-exposure prophylaxis (PrEP) have been available for several years. However, there is still no evidence on the level of knowledge of these HIV prevention tools among immigrants from sub-Saharan Africa living in precarious situations, a population particularly affected by HIV. The aim of this study is to describe the knowledge of these tools in this population and analyse the factors associated with this knowledge.

Methods

The data mobilized are from the Makasi interventional research that was conducted between 2018 and 2020 among immigrants from sub-Saharan Africa in precarious situations in the greater Paris area. Using data collected from 601 participants, we described levels of knowledge of HIV treatment effectiveness, treatment as prevention (TasP), post-exposure prophylaxis (PEP), and pre-exposure prophylaxis (PrEP), by sex with a chi2 test. We investigated factors associated with their knowledge with logistic regressions adjusted for sociodemographic characteristics, living conditions and sexual behaviors (p ≤ 0.2).

Results

The population surveyed was predominantly men (76%), from West Africa (61%) and in a precarious situation: 69% were unemployed, 74% were undocumented, 46% had no health coverage and 13% were homeless. In this population, knowledge of antiretroviral treatments for HIV prevention was heterogeneous: the effectiveness of HIV treatment was well known (84%), but only half of the respondents (46%) were aware of TasP and very few knew about PEP and PrEP: 6% and 5% respectively. Multivariable-adjusted models showed that these tools was better known by educated people, those who had a social network in France, those who have had access to the health system and those who were exposed to sexual risks.

Conclusions

While sub-Saharan African immigrants know the effectiveness of HIV treatment and use certain prevention tools such as HIV testing, they are not aware of PEP and PrEP.

Key messages

Analyzing implementation of public health interventions : a need for rigor, and the challenges of stakeholder involvement

OBJECTIVES

This article shows how conceptual models can help to develop and evaluate public health interventions. It also reports on the challenges of getting stakeholders involved.

METHOD

The analysis is based on the reflexive approach applied by the authors during their participation in two public health intervention research (PHIR) projects, in France and in Burkina Faso.

RESULTS

In Paris, PHIR aimed to enable sub-Saharan immigrants to appropriate the existing means of prevention and sexual health care and to strengthen their empowerment in view of preserving their health. Evaluation was carried out using mixed methods. The intervention process theory is based on Ninacs' conceptual model of individual empowerment. The Consolidated Framework For Implementation Research (CFIR) was mobilized a posteriori to analyze the process. PHIR stemmed from collaboration between a research team and two associations. The different stakeholders were involved in the evaluation process, as were, at certain times, persons in highly precarious situations. In Ouagadougou, a community-based dengue vector control intervention was deployed to address an essential but neglected need. As regards evaluation, we opted for a holistic, mixed method approach (effectiveness and process). The contents of the intervention were determined based on tacit knowledge, a community preference survey and solid evidence. The theoretical framework of the intervention consisted in an eco-biological model of vector control. The implementation analysis combined an internal assessment of implementation fidelity with an external CFIR process analysis. All stakeholders were involved in the evaluation process.

DISCUSSION

Analysis confirmed not only the value of process evaluations in PHIR, but also the primordial importance of a rigorous approach. Stakeholder involvement is a major challenge to be addressed early in the planning of RISPs; with this in mind, effective and ethically sound assessment mechanisms need to be drawn up. Interdisciplinary evaluative approaches should be preferred, and the use of justified, relevant, and flexible frameworks is highly recommended.

CONCLUSION

Lessons learned for those wishing to engage in the process evaluation of a public health intervention are hereby presented.

[Practices and Factors Associated with Recent HIV Testing in the General Population, Côte d'Ivoire: Results of the ANRS Study 12323 DOD-CI]

With 2.9% of HIV prevalence in the general population, Côte d'Ivoire is one of the countries most affected by the HIV epidemic in West Africa. In this country, only 63% of people infected with HIV are aware of their status. A cross-sectional phone survey was conducted with a representative sample of 3,867 individuals to describe the practices and factors associated with a recent HIV testing (≤ 1 year) in Côte d'Ivoire. Data relative to the last done HIV test as well as the socio-demographic characteristics, sexual behavior, access to information, perceptions, capacities and autonomy as well as social and geographical environment of the participants were collected. Logistical regression models were used to identify the associated factors with a recent HIV test (≤ 1 year). Lack of information is one of the main barriers to HIV testing (only 60% of individuals know a place to get tested). For men, despite the fact that HIV testing is free of charge, poor economic conditions seem to be a barrier to testing. The social environment, including peer influence, also appears to have an effect on testing among men. For women, testing is associated with their perceptions of HIV exposure. There is a need to rethink the current HIV testing communication in Côte d'Ivoire and to identify economic or social incentives to remove access barriers to HIV testing.

Effect of organizational models of provider-initiated testing and counseling (PITC) in health facilities on adult HIV testing coverage in sub-Saharan Africa

The purpose of this paper is to identify which Provider-Initiated HIV Testing and Counseling (PITC) organizational models are the most efficient to maximize testing coverage. We conducted a systematic literature review to identify published articles that evaluated routine PITC programs implemented in adult health facilities in Sub-Saharan Africa. We considered only articles measuring PITC offer, PITC acceptability and PITC coverage. Adjusted meta-regression models were performed to measure the association between PITC offer, acceptability and coverage with PITC organizational model. A total of 30 articles were included in the meta-analysis. Overall, 85.4% [95%CI: 77.2-93.5] of patients were offered a test, and 87.1% [82.4-91.7] accepted the test resulting in a PITC coverage of 74.3% [66-82.6]. Four types of PITC organizational models were identified: PITC initiated and performed during the consultation (model A), PITC initiated before consultation (model B), PITC referred on-site (model C) and PITC referred off-site (model D). Compared to model A, model B had a similar coverage (aOR: 1.02 [0.82-1.26]). However, coverage was lower for model C (aOR: 0.81 [0.68-0.97]) and model D (aOR: 0.58 [0.44-0.77]). Initiating the testing process before or during medical consultation is recommended for maximizing testing coverage among patients.

Total synthesis of amiclenomycin, an inhibitor of biotin biosynthesis

We describe the first synthesis of amiclenomycin, a natural product that has been found to inhibit biotin biosynthesis and, as a consequence, to exhibit antibiotic properties. Structure 1, with a trans relationship between the ring substituents. had previously been proposed for amiclenomycin on the basis of its 1H NMR spectrum. We have prepared the trans and cis isomers 1 and 2 by unequivocal routes and we conclude that the natural product is in fact the cis isomer 2. The properly substituted cyclohexadienyl rings were constructed first. A cycloaddition reaction between 1,2-di(phenylsulfonyl)ethylene and the N-allyloxycarbonyl diene 13, followed by reductive elimination of the phenylsulfinyl groups, gave the cis isomer 15. To obtain the trans isomer, the O-trimethylsilyl diene was used to give the cis hydroxylated Diels-Alder adduct 33, which was transformed into the corresponding trans amino derivative by means of a Mitsunobu reaction. The L-alpha-amino acid functionality was introduced by means of a Strecker reaction on the aldehydes 16 and 42, followed by enzymatic hydrolysis with immobilised pronase.

Slow-binding and competitive inhibition of 8-amino-7-oxopelargonate synthase, a pyridoxal-5'-phosphate-dependent enzyme involved in biotin biosynthesis, by substrate and intermediate analogs. Kinetic and binding studies

8-Amino-7-oxopelargonate synthase catalyzes the first committed step of biotin biosynthesis in micro-organisms and plants. Because inhibitors of this pathway might lead to antibacterials or herbicides, we have undertaken an inhibition study on 8-amino-7-oxopelargonate synthase using six different compounds. d-Alanine, the enantiomer of the substrate of this pyridoxal-5'-phosphate-dependent enzyme was found to be a competitive inhibitor with respect to l-alanine with a Ki of 0.59 mm. The fact that this inhibition constant was four times lower than the Km for l-alanine was interpreted as the consequence of the inversion-retention stereochemistry of the catalyzed reaction. Schiff base formation between l or d-alanine and pyridoxal-5'-phosphate, in the active site of the enzyme, was studied using ultraviolet/visible spectroscopy. It was found that l and d-alanine form an external aldimine with equilibrium constants K = 4.1 mm and K = 37.8 mm, respectively. However, the equilibrium constant for d-alanine aldimine formation dramatically decreased to 1.3 mm in the presence of saturating concentration of pimeloyl-CoA, the second substrate. This result strongly suggests that the binding of pimeloyl-CoA induces a conformational change in the active site, and we propose that this new topology is complementary to d-alanine and to the putative reaction intermediate since they both have the same configuration. (+/-)-8-Amino-7-oxo-8-phosphonononaoic acid (1), the phosphonate derivative of the intermediate formed during the reaction, was our most potent inhibitor with a Ki of 7 microm. This compound behaved as a reversible slow-binding inhibitor, competitive with respect to l-alanine. Kinetic investigation showed that this slow process was best described by a one-step mechanism (mechanism A) with the following rate constants: k1 = 0.27 x 103 m-1.s-1, k2 = 1.8 s-1 and half-life for dissociation t1/2 = 6.3 min. The binding of compound 1 to the enzyme was also studied using ultraviolet/visible spectroscopy, and the data were consistent with the kinetic data (K = 4.2 microm). Among the other compounds tested, two potential transition state analogs, 4-carboxybutyl(1-amino-1-carboxyethyl)phosphonate (4) and 2-amino-3-hydroxy-2-methylnonadioic acid (5) were found to be competitive inhibitors with respect to l-alanine with Ki of 68 microm and 80 microm, respectively.