Essay #1 – Factors influencing the risk of falls in the construction industry: a review of the evidence Falls are a significant public health risk and a leading cause of nonfatal and fatal injuries among construction workers worldwide. A more comprehensive understanding of casual factors leading to fall incidents is essential to prevent falls in the construction industry. However, an extensive overview of causal factors is missing from the literature. In this paper, 536 articles on factors contributing to the risk of falls were retrieved. One hundred twenty-one (121) studies met the criteria for relevance and quality to be coded, and were synthesized to provide an overview. In lieu of the homogeneity needed across studies to conduct a structured meta-analysis, a literature synthesis method based on macro-variables was advanced. This method provides a flexible approach to aggregating previous findings and assessing agreement across those studies. Factors commonly associated with falls included working surfaces and platforms, workers’ safety behaviors and attitudes, and construction structure and facilities. Significant differences across qualitative and quantitative studies were found in terms of focus, and areas with limited agreement in previous research were identified. Findings contribute to research on the causes of falls in construction, developing engineering controls, informing policy and intervention design to reduce the risk of falls, and improving research synthesis methods. Essay #2 – Review of quantitative studies of interventions for responding to infectious disease outbreaks We reviewed the modeling and retrospective literature on responding to outbreaks of infectious diseases in humans and animals. Unlike routine immunization and control efforts, outbreak response activities require rapid reactive actions to address an urgent or emergent situation. We focused our review on characterizing the types of diseases analyzed, the interventions used, and the models employed. Out of the 211 studies identified, we find that the majority focus on a few diseases (influenza, foot and mouth disease, smallpox, measles, and hepatitis). We identified 34 distinct interventions explored in these studies that fall under the general categories of vaccination, prophylaxis, quarantine/isolation, contact restriction, exposure reduction, killing/slaughtering, and surveillance. A large number of studies (141) use simulation/analytical models to analyze outbreak response strategies. We identify key factors contributing to the effectiveness of different interventions that target high-risk individuals, trace infected contacts, or use a ring to delineate geographical boundaries for an intervention. Essay #3 – Development of an individual-based model for polioviruses: implications of the selection of network type and outcome metrics We developed an individual-based (IB) model to explore the stochastic attributes of state transitions, the heterogeneity of the individual interactions, and the impact of different network structure choices on the poliovirus transmission process in the context of understanding the dynamics of outbreaks. We used a previously published differential equation-based model to develop the IB model and inputs. To explore the impact of different types of networks, we implemented a total of 26 variations of six different network structures in the IB model. We found that the choice of network structure plays a critical role in the model estimates of cases and the dynamics of outbreaks. This study provides insights about the potential use of an IB model to support policy analyses related to managing the risks of polioviruses and shows the importance of assumptions about network structure. / Ph. D.

This research explores how community-centered solutions facilitate the success and ownership of the response actions to deal with a public health emergency, such as the Covid-19 pandemic. When an outbreak or a hazard impacts a group of people, there is a strong need for communication in order to be able to access to the right information that takes people to make the correct decision and thus to take a protective action to be safe. This approach, known as Risk Communication and Community Engagement (RCCE)[1], allows the co-production of knowledge needed for a group of people to remain safe. For this approach, social listening tools, such as media monitoring and community feedback collection are critical understand communities’ needs. Its analysis allows to tailor a RCCE strategy that is able to substantially reduce the threat that a public health emergency poses to human lives[2].  Communities need solutions that are adapted to their needs in order to be able to deal with any emergency, including the Covid-19 pandemic. The RCCE approach empowers communities and provides them with the tools to amplify their voices. This participatory approach allows them to co-produce knowledge and get full ownership of the solutions.  Nevertheless, in an environment with excess of information, it may not be easy to discern the truth from the false. Unverified information and rumors are frequent and social media channels facilitate their rapid dissemination without borders. ‘Infodemic’ refers to an excessive amount of information concerning a problem such that the solution is made more difficult. (WHO, 2020)[3]  Some rumors may encourage people to take wrong decisions and perform actions that exacerbate risks during an emergency. The RCCE approach helps to promote real-time exchange of information to avoid that rumors and disinformation flourish. (WHO, 2018)[4]. It also allows to identify and implement community-centered solutions to communities’ problems.  RCCE needs data to monitor and evaluate its activities and reach effectively populations in risk to encourage them to observe the health preventive measures. Lives at risk depends on the right information conveyed through the right channel at the right time. To be able to supply tailored and accurate information to those communities and engage them, evidence-based RCCE strategies are needed, respecting the socio-anthropological and cultural context of the community. This research is based on the findings from five African countries -Cabo Verde, Cameroon, the Gambia, Mozambique and Niger-, all of them seriously affected by current Covid-19 pandemic. Its conclusions help to understand the critical role that RCCE plays in health emergencies resilient recovery.   [1] World Health Organization (WHO) (‎2020)‎. Risk communication and community engagement (‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎RCCE)‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎ readiness and response to the 2019 novel coronaviruses (‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎2019-‎‎nCoV)‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎‎: interim guidance, 26 January 2020. Geneva: WHO. [2] Risk Communication is one of the eight core functions of the International Health Regulations (2005) [3] World Health Organization (WHO) (‎2020)‎. Infodemic management: a key component of the COVID-19 global response. Weekly Epidemiological Record 95 (‎16)‎, 145 - 148. World Health Organization.  [4] World Health Organization (WHO) (2018). Communicating Risk in Public Health Emergencies - A WHO Guideline for Emergency Risk Communication (ERC) policy and practice. Geneva: World Health Organization.