Factors associated with ART interruption during the COVID-19 crisis in Burundi (the EPIC community-based research program).

With a national prevalence of 0.9%, Burundi is close to achieving UNAIDS' 2025 targets. Despite this, different types of crises periodically disrupt its HIV health services. The community-based program EPIC measured the impact of the COVID-19 health crisis on people living with HIV (PLHIV) in Burundi in 2021. Specifically, it assessed ART interruption and associated factors since the beginning of the pandemic. The study questionnaire was administered to PLHIV in three cities between October and November 2021. Participants were recruited using convenience sampling. Logistic regression models helped identify factors associated with ART interruption. Of the 317 respondents, 37 (11.7%) reported interruption. The majority (79.2%) self-identified as belonging to key populations. Interruption was significantly associated with: fewer HIV medical follow-up visits (adjusted Odds Ratio, aOR = 7.80, p = 0.001) and forced HIV status disclosure (aOR = 4.10, p = 0.004). It was inversely associated with multi-month ART dispensing (aOR = 0.36, p = 0.017) since the beginning of the pandemic and the perception of not having been sufficiently informed by the HIV medical team about the risk of COVID-19 infection (aOR = 0.11, p < 0.001). Our results highlight the importance of multi-month ART dispensing, enhanced communication, and voluntary disclosure of one's HIV status in preventing ART interruption in times of crises in Burundi.

Entre science et engagement : les défis de la recherche communautaire au sein du réseau Coalition PLUS.

Community-based research, that is, the meaningful involvement of affected populations in the production of scientific knowledge that concerns them, is a political struggle and an ethical necessity. Coalition PLUS, an international network of organizations (most of them NGOs) fighting against HIV and hepatitis, created a community-based research laboratory (CBRL) composed of people from more than sixteen countries and various disciplinary fields. The objectives of the CBLR are to build research capacity, ensure collaboration with local and international academic research centers, and develop international research projects. The CBRL acts as a bridge between different partners, reconciling sometimes divergent interests, and must provide mediation and support to promote dialogue, transparency, and a relationship of trust between the communities and academic researchers. However, the need for scientific legitimacy obliges us to continuously seek a balance between responding to the needs of the field and using rigorous scientific methods, while optimizing and prioritizing existing resources. The permanent quest for this balance has led the CBRL to reorganize its mode of operation to optimize existing synergies with academic research laboratories, with a view to asserting its scientific legitimacy and continuing to contribute to social transformation through community-based research that is both innovative and of high quality. This paper provides a critical reflection on the issues, challenges, practices, and solutions of community-based research within the Coalition PLUS network.

When awareness is not a barrier to PrEP uptake among men who have sex with men who are eligible for PrEP in France.

Despite PrEP being available and free of charge in France, a gap remains between the estimated number of men who have sex with men (MSM) with high-risk exposure to HIV and the number of MSM PrEP users. The objective of this study is to identify factors associated with non-intention to use PrEP among PrEP-eligible and PrEP-aware MSM in France, "non-intenders".European MSM Internet Survey (EMIS)-2017 was a cross-sectional survey conducted among MSM concerning their HIV prevention needs. Logistic regression models were used to identify factors associated with "non-intenders".Compared to PrEP users, factors associated with non-intention to use PrEP were: age (aOR[95%CI] = 3.80[2.21;6.53]); not being vaccinated against hepatitis B (2.20[1.45;3.34]); self-efficacy (1.84[1.29;2.60]); lower knowledge about on-demand PrEP (11.48[7.37;17.87]) and daily PrEP (2.58[1.27;5.25]); not having a PrEP discussion at a hospital (12.39[8.90;17.27]) or at a community service/drop-in (4.93[3.48;6.97]); living in a department with few PrEP access points (1.70[1.10;2.63]).On-demand PrEP may meet the prevention needs of "non-intenders" who have lower HIV risk perception. Increasing communication from health providers and community health workers to all MSM is needed.

Impact of the COVID-19 Health Crisis on Key Populations at Higher Risk for, or Living With, HIV or Hepatitis C Virus and People Working With These Populations: Multicountry Community-Based Research Study Protocol (EPIC Program).

BACKGROUND: Information concerning the impact of the COVID-19 health crisis on populations most affected by HIV and hepatitis C virus (HCV; or key populations [KP]), and those working with these populations in community settings, is limited. Community-based organizations working in the field of HIV and viral hepatitis are well placed to identify and meet the new needs of KP owing to the health crisis. OBJECTIVE: This study aims to describe the development and implementation of an exploratory and descriptive multicountry, community-based research program, EPIC (Enquêtes Pour évaluer l'Impact de la crise sanitaire covid en milieu Communautaire), within an international network of community-based organizations involved in the response to HIV and viral hepatitis. The EPIC program aimed to study the impact of the COVID-19 health crisis on KP or people living with HIV or HCV and people working with these populations at the community level (community health workers [CHWs]) and to identify the key innovations and adaptations in HIV and HCV services. METHODS: A general protocol and study documents were developed and shared within the Coalition PLUS network. The protocol had a built-in flexibility that allowed participating organizations to adapt the study to local needs in terms of the target population and specific themes of interest. Data were collected using surveys or interviews. RESULTS: From July 2020 to May 2022, a total of 79 organizations participated in the EPIC program. Across 32 countries, 118 studies were conducted: 66 quantitative (n=12,060 among KP or people living with HIV or people living with HCV and n=811 among CHWs) and 52 qualitative (n=766 among KP or people living with HIV or people living with HCV and n=136 among CHWs). CONCLUSIONS: The results of the EPIC program will provide data to describe the impact of the health crisis on KP and CHWs and identify their emerging needs. Documentation of innovative solutions that were put into place in this context may help improve the provision of services after COVID-19 and for future health crises. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/45204.

Resilience outcomes and associated factors among workers in community-based HIV care centres during the Covid-19 pandemic: A multi-country analysis from the EPIC program.

Introduction: Community health workers (CHW) were integral in the COVID-19 response, particularly concerning services for populations vulnerable to HIV. Little is known regarding the mental health of CHW during the COVID-19 crisis. The objective of this study was to study resilience of CHW working in HIV non-governmental organizations. Methods: An anonymous online, cross-sectional questionnaire was implemented during 2021 among CHW in Benin, Colombia, Guatemala, and Spain. Three scales were used to assess mental health: the 6-item Brief-Resilience Scale, the 9-item Patient Scale Questionnaire and the 7-item Generalized-Anxiety-Disorder scale. Logistic regression models were used to identify factors associated with "low" resilience vs "normal" or "high" resilience. Results: Among 295 respondents, the median standardized resilience score was 58.33 (IQR = [50.0-75.0], n = 267), 18.52 (IQR = [7.4-33.3], n = 282) for standardized depression score and 19.05 (IQR = [4.8-33.3], n = 274) for standardized anxiety score. Standardized resilience score was negatively correlated with standardized anxiety score (rho = -0.49, p < 0.001, n = 266) and standardized depression score (rho = -0.44, p < 0.001, n = 267). Conclusions: Normal or high level of resiliency in the HIV CHW were observed during the COVID-19 crisis. Self-efficacy, through COVID-19 prevention training, was a factor associated with resilience. Health policy must place CHW at the core of the healthcare system response to Covid-19 and to future health emergencies, as they ensure continuity of care for many diseases including HIV among vulnerable populations.

Fear of stigma from health professionals and family/neighbours and healthcare avoidance among PLHIV in Morocco: results from the Stigma Index survey Morocco.

BACKGROUND: Enacted or anticipated stigma among people living with HIV (PLHIV) can negatively impact healthcare engagement. We identified factors associated with having avoided HIV health services for fear of stigma among PLHIV in Morocco. METHODS: The Stigma Index survey was conducted in Morocco in March-June 2016. Factors associated with avoiding HIV testing and treatment services for fear of stigma by (A) health personnel or family/neighbours and (B) health personnel and family/neighbours compared to people who did not avoid health services for fear of stigma from either of the two sources were assessed using multinomial logistic regression models. RESULTS: Among 583 respondents, 280 (48.0%) were women and median number of years living with HIV was 5[IQR:2-7]. Half of the respondents reported avoiding health services for fear of stigma by health personnel and/or family/neighbours: (A) n = 228, 39.1% and (B) n = 68, 11.7%. After adjustment on perceived health status, not having had easy access to antiretroviral treatment ((A) aRR [95% CI] = 1.76[1.16; 2.68]; (B) 2.18[1.11; 4.27]), discrimination by PLHIV ((A) 1.87[1.12; 3.13]; (B) 3.35[1.63; 6.88]) and exclusion from social activities ((A) 1.70[1.10; 2.61]; (B) 2.63[1.39; 5.00]) were associated with having avoided health services for fear of stigma by health personnel or/and family/neighbours. Being female (2.85[1.48; 5.47]), not having been referred for an HIV test for suspected symptoms 3.47[1.67; 7.22], having discussed sexual/reproductive health with a health professional (4.56[2.38; 8.71]), and not having the feeling to influence decisions on local projects for PLHIV (3.47[1.37; 7.83], were associated with having avoided health services for fear of stigma by both sources. CONCLUSION: Results suggest a cumulative effect of fear of stigma and discrimination among PLHIV in Morocco. PLHIV who have experienced discrimination may seek to avoid similar situations at the expense of their health. These results should inform multi-level interventions and broader advocacy efforts to reduce stigma and discrimination.

PrEP in the Context of Other HIV Risk Reduction Strategies Among Men Who Have Sex with Men: Results from the Flash! PrEP in Europe Survey.

Combination HIV prevention covers a range of biomedical, behavioral, and socio-structural interventions. Despite the growing availability of pre-exposure prophylaxis (PrEP), it is not always accessible in European Centre for Disease Prevention and Control reporting countries and may not meet the needs of all at-risk populations. Based on the Flash! PrEP in Europe data, multiple correspondence analysis and hierarchical clustering were used to identify patterns in HIV prevention strategies among 9980 men who have sex with men (MSM). PrEP interest was evaluated among four identified clusters: (A) "high condom use, sometimes Treatment as Prevention (TasP)"; (B) "mix of methods, infrequent condom use"; (C) "high condom use, tendency to choose partners based on serological status" and (D) "moderate use of condoms mixed with other prevention strategies". Clusters B and D had higher PrEP interest. These results suggest that MSM use a range of behavioral and biomedical risk reduction strategies that are often combined. On-demand PrEP may meet the needs of MSM who infrequently use condoms and other prevention methods.

La recherche communautaire en temps de pandémie : retour sur l'étude multi-pays EPIC.

In 2020, the COVID-19 health crisis affected all regions of the world, not sparing people already vulnerable to other viral epidemics such as HIV or HCV and/or those in precarious or socially marginalized situations. This is particularly the case for drug users or sex workers.Coalition PLUS, a network of associations fighting against HIV and viral hepatitis which defends and promotes the community-based approach, and its partners, have set up a multi-country community-based research project aimed at documenting the impact of the health crisis on the fight against HIV and viral hepatitis (key populations and community workers/activists), as well as the community responses put in place (EPIC survey).The objective of this paper is to reflect on the implementation of this community-based research study during the COVID-19 health crisis, and in particular the unforeseen difficulties to which the community-based research process had to confront and adapt. The goal is to draw lessons on what worked (and what did not work) in order to capitalize on community-based research practices during this pandemic and subsequently, facilitate the implementation of new research projects in similar contexts.

Impact of the early 2020 COVID-19 crisis and lockdown on PrEP use among men who have sex with men (MSM) in France.

OBJECTIVE: To describe changes in pre-exposure prophylaxis (PrEP) use during and following the COVID-19 lockdown in France (March-May 2020) and identify the factors associated with PrEP discontinuation among men who have sex with men (MSM) after the lockdown. METHODS: Data from the, an anonymous, cross-sectional internet survey among MSM in July 2020, were analysed. Among respondents who were using PrEP prior to the lockdown, a binary logistic regression model was used to compare participants who were still taking PrEP (current PrEP users) with those who were not taking PrEP at the time of the survey (former PrEP users). RESULTS: Among 8345 respondents, 946 were PrEP users before the lockdown, of whom 58.8% (n=556) reported stopping PrEP during the lockdown and 15.4% (n=146) were not using PrEP at the time of the survey. Among the 556 who stopped PrEP during lockdown, 86.5% (n=481) reported no sexual activity; 76.8% (n=427) restarted PrEP after lockdown. Former PrEP users were more likely to be younger, not living with a stable male sexual partner, report moderate anxiety, report increased psychoactive drug use during the lockdown, and report not having tested for HIV or STI since the end of the lockdown because they did not know where to go, preferred to wait or for another reason. Reporting fewer male sexual partners in the last 6 months was also significantly associated with being a former PrEP user. CONCLUSIONS: MSM adapted PrEP use to their sexual activity during and after the French lockdown. After the lockdown, discontinued PrEP occurred more often among MSM who had fewer sexual partners and had mental health vulnerabilities. These factors could also be predictive of PrEP discontinuation in a more general context. PrEP users should be informed on how to safely stop/start PrEP and on the use of other prevention tools to reduce potential risk exposure during PrEP discontinuation.

"Yes, I'm interested in taking PrEP!": PrEP interest among women respondents to the European community-based survey "Flash! PrEP in Europe".

The World Health Organization recommends pre-exposure prophylaxis (PrEP) for all populations at substantial risk of HIV infection, including women. However, data regarding PrEP interest among women is lacking, particularly in Europe. Factors associated with interest in using PrEP were assessed among women respondents to the Flash! PrEP in Europe (FPIE) survey. This community-based cross-sectional study, conducted in 12 European countries, aimed to assess PrEP knowledge and interest. "High objective risk" (HOR) was assessed using established risk criteria following EACS and CDC guidelines. Factors associated with interest in using PrEP were assessed in univariable and multivariable logistic regression models. Among 678 women, 12.5% (n = 85) were considered at HOR, 46.8% (n = 317) indicated prior PrEP knowledge and 18.0% (n = 122) reported interest in using PrEP. Among women at HOR, 40.0% (n = 34) were interested in PrEP. Factors significantly associated with PrEP interest in the final multivariable model were: younger age (18-29 years) (aOR 1.91[95CI: 1.07; 3.41]), bad self-perceived financial status (1.84[1.09; 3.11]), migrant status (south to north) (2.87[1.05; 7.89]), single or dating relationship status (1.93[1.23; 3.03]), sexual abuse history (1.86[1.17; 2.97]), "rather high"/ "high" self-perceived HIV risk (3.21[1.32; 7.81]), and HOR (2.49[1.42; 4.35]). These results show that women at HOR and those who perceived themselves to be at high risk are interested in using PrEP. There is a critical need for targeted information and improved access to PrEP to increase uptake of this HIV prevention tool to meet PrEP interest among women.

Determinants and effects or consequences of internal HIV-related stigma among people living with HIV in Morocco.

BACKGROUND: HIV-related stigma and discrimination constitute a barrier to different intervention programs. Unlike external stigma, internal stigma is not well explored in in the Middle East and North African countries, while grasping this particular form of stigma is essential to limit its effects. The present study aims to measure internal stigma effects and to identify factors associated with this kind of stigma not yet documented among people living with HIV (PLHIV) in Morocco. METHODS: The PLHIV Stigma Index questionnaire (adapted and translated into French and Moroccan Arabic dialect "darija") was used to collect information regarding the stigma and discrimination experienced by PLHIV across 8 cities in Morocco (September-October 2016). A randomly drawn cluster of 10 PLHIV, consisting of 5 men and 5 women, was drawn at each participating medical care center to achieve a nationally representative sample of PLHIV. Fifteen interviewers living with HIV and five supervisors were selected and trained to administer the questionnaire. An internal stigma score (range: 0-7), was calculated based on seven negative feelings/ beliefs. Negative binomial regression was used to identify characteristics associated with the internal stigma score. RESULTS: Among 626 PLHIV, internal stigma was reported by 88.2%. The median [IQR] internal stigma score was 4 [2-5]. Regarding internal stigma, 51% avoided going to the local clinic when needed and 44% chose not to attend social gatherings. Belonging to at least one key population (aIRR [95%CI] = 1.15 [1.03; 1.28]), experiencing discriminatory reactions from family following HIV status disclosure (1.28 [1.11; 1.49]), avoiding HIV services for fear of stigmatization by staff (1.16 [1.05; 1.28]) and being denied health services because of HIV status (1.16 [1.03;1.32]), are among the factors significantly associated with an increase of the internal stigma score. CONCLUSIONS: Internal stigma is high among Moroccan PLHIV and significantly impacting their life decisions and their healthcare access. Multi-level interventions are needed to address internal stigma experienced by PLHIV in Morocco.

Assessment of mental health outcomes and associated factors among workers in community-based HIV care centers in the early stage of the COVID-19 outbreak in Mali.

BACKGROUND AND OBJECTIVES: In Mali, the non-governmental association (NGO) ARCAD Santé PLUS launched the CovidPrev program in response to the COVID-19 outbreak to ensure continuity of HIV care-related activities. This study aimed to identify individual and structural factors associated with mental health disorders (MHD) in the NGO's healthcare workers (HCW) in the early stage of the outbreak. METHODS: Data were collected between April 6 and 11, 2020 for 135 HCW in ARCAD Santé PLUS's 18 community-based HIV care centers. Outcomes corresponded to the PHQ-9, GAD-7 and ISI instruments for depression, anxiety and insomnia, respectively. A general mixture model with a negative binomial distribution was implemented. RESULTS: Most HCW were men (60.7%) and median age was 40 years IQR[33-46]. Symptoms of depression, anxiety and insomnia were declared by 71.9, 73.3, and 77% participants, respectively. Women were at greater risk of MHD. A lack of personal protection equipment and human resources, especially nurses, was associated with a high risk of MHD. CONCLUSIONS: Health policy must place non-front line HCW, including those in NGOs, at the core of the healthcare system response to the COVID-19 outbreak, as they ensure continuity of care for many diseases including HIV. The efficacy of public health strategies depends on the capacity of HCW to fully with and competently perform their duties.

PrEP Interest Among Men Who Have Sex with Men in the Netherlands: Covariates and Differences Across Samples.

Despite increased availability of pre-exposure prophylaxis (PrEP), PrEP uptake has remained low. To promote uptake, factors related to PrEP interest among relevant target populations warrant investigation. The aim of this study was to provide an analysis of PrEP interest among men who have sex with men (MSM) in the Netherlands, while taking study recruitment strategies into account. We recruited 154 MSM from an LGBT research panel (AmsterdamPinkPanel) and 272 MSM from convenience sampling. Both samples were part of the Flash! PrEP in Europe Survey and were compared on their PrEP interest, usage intentions, and sexual behavior. We conducted logistic regression analyses to discover variables associated with PrEP interest and intentions. Participants from the AmsterdamPinkPanel were less likely to use PrEP, had less knowledge of PrEP, and were less interested in PrEP than participants from convenience sampling. Significant covariates of PrEP interest were being single, more prior PrEP knowledge, sexual risk behaviors, such as not having used a condom during last sex and having ever used drugs in a sexual context, and not participating in the AmsterdamPinkPanel. Adding the recruitment strategy to the regression increased explained variance on top of predictors already described in the literature. Increased sexual risk behavior is related to increased PrEP interest and it helps to identify PrEP target groups. Recruitment strategies have a substantial impact on findings regarding PrEP interest and usage intentions. This study emphasizes the importance of using multiple strategies for recruiting participants to obtain a more comprehensive view of MSM's attitudes toward PrEP.

Are PrEP services in France reaching all those exposed to HIV who want to take PrEP? MSM respondents who are eligible but not using PrEP (EMIS 2017).

Pre-exposure prophylaxis (PrEP) is fully reimbursed by the French health insurance system since 2016. However, uptake of PrEP is slower than expected and little is known about men who have sex with men (MSM) who are eligible for PrEP according to French guidelines, but not using it. This study aims to (1) assess and describe MSM that are eligible to PrEP but not using it, and (2) identify potential individual and structural barriers of PrEP uptake among eligible MSM who are aware and intend to take PrEP. Data from EMIS-2017, a cross-sectional internet survey among gay, bisexual, and other MSM, were used. Among 7965 respondents without diagnosed HIV, 9.2% were PrEP users. Among 7231 non-PrEP users, 35.2% were eligible to PrEP and 15.2% were eligible, aware and intended to take PrEP. Eligible MSM who are not using PrEP are mostly younger, students, less "out", living in small cities, using condoms more frequently but still with low self-efficacy regarding safe sex and more distant from preventive health care and information than PrEP users. Despite free PrEP availability in France, results suggest that PrEP is not fully accessible and that there is a need to increase PrEP demand and decentralize PrEP delivery.

Give PrEP a chance: moving on from the "risk compensation" concept.

INTRODUCTION: While bio-behavioural interventions (BIs) for sexually transmitted infections (STIs) and HIV prevention have shown their effectiveness (e.g. treatment for syphilis, HPV vaccination or pre-exposure prophylaxis [PrEP]), they have also aroused major concerns regarding behavioural changes that could counteract their benefit. Risk compensation (RC) fears concerning BIs in the HIV/STIs prevention field are intimately linked to representations, judgements and social control on sexual behaviour. With an increasing number of PrEP studies describing a rise in STIs due to RC, this paper argues for a shift away from the focus on RC and proposes a more constructive approach to respond to the needs of people living with HIV and populations most at risk. DISCUSSION: The concept of RC, stemming from road safety and derived from economic theory, relies on rational theoretical models of human behaviour. Although widely applied in several contexts its use has been reasonably questioned. Major methodological issues regarding RC have been raised within HIV/AIDS literature. Although behavioural changes (e.g. condomless sex and number of sexual partners) are often erroneously assimilated with RC, there is no evidence that behavioural changes have undermined the effectiveness of previous and current BIs. Still, PrEP has not escaped RC concerns. Increases in condomless sex within the context of growing uptake of PrEP signals a continued need for integrated and innovative HIV and STI prevention strategies and a comprehensive sexual health approach. Routine HIV/STI testing, peer-led counselling, and identification of sexual health needs within the PrEP model of care could become a gold standard in the sexual health field for all populations. CONCLUSIONS: RC remains a frequent argument against the availability and provision of prevention methods for vulnerable populations. Individuals should be able to benefit from the full panel of BIs options available, to find and adapt methods according to their needs. Current, past and future PrEP users, with other stakeholders, may provide valuable insight into innovative solutions and programmes to control HIV and other STIs.

Antibody persistence and serological protection among seasonal 2007 influenza A(H1N1) infected subjects: Results from the FLUREC cohort study.

INTRODUCTION: Haemagglutination-inhibition (HI) antibody titer is a correlate of protection against influenza; its persistence after infection or vaccination is important to determining susceptibility to subsequent infection. Few studies, however, have reported longitudinal data regarding the magnitude and duration of HI protection following natural seasonal influenza A infection. METHODS: Using French influenza cohort study data collected from 2008 to 2010, we investigated persistence of serological protection among subjects according to influenza-like illness (ILI) and laboratory-confirmed seasonal 2007 influenza A(H1N1) infection status at inclusion in 2008 (ILI-A(H1N1) positive, ILI-A(H1N1) negative, or no-ILI). Antibody titers against seasonal 2007 A(H1N1) were determined using the HI technique for sera. Regression models for interval-censored data were used to estimate geometric mean titers (GMT) for HI assays. A logistic regression model adjusted for age group (subjects <30, 30-50 and >50 years old) was used to quantify the association between HI titer and protection against infection. RESULTS: Based on 310 total subjects, influenza A(H1N1) infection was confirmed in 39 of 115 ILI subjects at inclusion. GMT associated with 50% probability of protection among ILI subjects decreased with age group (subjects <30 yo: GMT of 40.8 was associated with 50% [95CI: 29.3%; 70.7%] probability of protection, subjects 30-50 yo: 26.8 [95CI: 34.4%; 65.6%] and subjects >50 yo: 8.9 [95CI: 15.3%; 84.7%]). GMT declined after the first annual study visit among ILI-A(H1N1) positive subjects but remained higher compared to inclusion at the 2010 study visit (41.5 [95CI: 34.8; 49.5], p=0.0157). GMT remained stable among ILI-A(H1N1) negative subjects (p=0.7502), but decreased among no-ILI subjects (p<0.0001). CONCLUSION: Our results confirm the positive relationship between HI titer and probability of protection among naturally infected subjects, and provides evidence that protection associated with HI titer varies with age. This longitudinal analysis suggests the rise in HI titers following seasonal 2007 influenza A(H1N1) infection may persist into subsequent influenza seasons.

Causal analysis of H1N1pdm09 influenza infection risk in a household cohort.

BACKGROUND: Obtaining a comprehensive quantitative figure of the determinants of influenza infection will help identify priority targets for future influenza mitigation interventions. We developed an original causal model integrating highly diverse factors and their dependencies, to identify the most critical determinants of pandemic influenza infection (H1N1pdm09) during the 2010-2011 influenza season. METHODS: We used data from 601 households (1450 participants) included in a dedicated cohort. Structural equations were used to model direct and indirect relationships between infection and risk perception, compliance with preventive behaviours, social contacts, indoor and outdoor environment, sociodemographic factors and pre-epidemic host susceptibility. Standardised estimates (ßstd) were used to assess the strength of associations (ranging from -1 for a completely negative association to 1 for a completely positive association). RESULTS: Host susceptibility to H1N1pdm09 and compliance with preventive behaviours were the only two factors directly associated with the infection risk (ßstd=0.31 and ßstd=-0.21). Compliance with preventive behaviours was influenced by risk perception and preventive measures perception (ßstd=0.14 and ßstd=0.27). The number and duration of social contacts were not associated with H1N1pdm09 infection. CONCLUSIONS: Our findings suggest that influenza vaccination in addition to public health communication campaigns focusing on personal preventive measures should be prioritised as potentially efficient interventions to mitigate influenza epidemics.

Risk factors of pandemic influenza A/H1N1 in a prospective household cohort in the general population: results from the CoPanFlu-France cohort.

BACKGROUND: The CoPanFlu-France household cohort was set up in 2009 to identify risk factors of infection by the pandemic A/H1N1 (H1N1pdm09) virus in the general population. OBJECTIVES: To investigate the determinants of infection during the 2010-2011 season, the first complete influenza season of study follow-up for this cohort. PATIENTS/METHODS: Pre- and post-epidemic blood samples were collected for all subjects, and nasal swabs were obtained in all subjects from households where an influenza-like illness was reported. Cases were defined as either a fourfold increase in the serological titer or a laboratory-confirmed H1N1pdm09 on a nasal swab, with either RT-PCR or multiplex PCR. Risk factors for H1N1pdm09 infections were explored, without any pre-specified hypothesis, among 167 individual, collective and environmental covariates via generalized estimating equations modeling. We adopted a multimodel selection procedure to control for model selection uncertainty. RESULTS: This analysis is based on a sample size of 1121 subjects. The final multivariable model identified one risk factor (history of asthma, OR = 2.17; 95% CI: 1.02-4.62) and three protective factors: pre-epidemic serological titer (OR = 0.51 per doubling of the titer; 95% CI: 0.39-0.67), green tea consumption a minimum of two times a week (OR = 0.39; 95% CI: 0.18-0.84), and proportion of subjects in the household always covering their mouth while coughing/sneezing (OR = 0.93 per 10% increase; 95% CI: 0.86-1.00). CONCLUSION: This exploratory study provides further support of previously reported risk factors and highlights the importance of collective protective behaviors in the household. Further analyses will be conducted to explore these findings.

Factors associated with post-seasonal serological titer and risk factors for infection with the pandemic A/H1N1 virus in the French general population.

The CoPanFlu-France cohort of households was set up in 2009 to study the risk factors for infection by the pandemic influenza virus (H1N1pdm) in the French general population. The authors developed an integrative data-driven approach to identify individual, collective and environmental factors associated with the post-seasonal serological H1N1pdm geometric mean titer, and derived a nested case-control analysis to identify risk factors for infection during the first season. This analysis included 1377 subjects (601 households). The GMT for the general population was 47.1 (95% confidence interval (CI): 45.1, 49.2). According to a multivariable analysis, pandemic vaccination, seasonal vaccination in 2009, recent history of influenza-like illness, asthma, chronic obstructive pulmonary disease, social contacts at school and use of public transports by the local population were associated with a higher GMT, whereas history of smoking was associated with a lower GMT. Additionally, young age at inclusion and risk perception of exposure to the virus at work were identified as possible risk factors, whereas presence of an air humidifier in the living room was a possible protective factor. These findings will be interpreted in light of the longitudinal analyses of this ongoing cohort.