key: cord-0699961-hr7qm0wm authors: Yi, Huso; Ng, Shu Tian; Farwin, Aysha; Low, Pei Ting Amanda; Chang, Cheng Mun; Lim, Jeremy title: Health equity considerations in COVID-19: geospatial network analysis of the COVID-19 outbreak in the migrant population in Singapore date: 2020-09-07 journal: J Travel Med DOI: 10.1093/jtm/taaa159 sha: 04c3b386105a610e7d035d5e7f9c3ce3ec01d605 doc_id: 699961 cord_uid: hr7qm0wm BACKGROUND: Low-wage dormitory-dwelling migrant workers in Singapore were disproportionately affected by coronavirus disease 2019 (COVID-19) infection. This was attributed to communal living in high-density and unhygienic dormitory settings and a lack of inclusive protection systems. However, little is known about the roles of social and geospatial networks in COVID-19 transmission. The study examined the networks of nonwork-related activities among migrant workers to inform the development of lockdown exit strategies and future pandemic preparedness. METHODS: A population-based survey was conducted with 509 migrant workers across the nation, and it assessed dormitory attributes, social ties, physical and mental health status, COVID-19-related variables, and mobility patterns using a grid-based network questionnaire. Mobility paths from dormitories were presented based on purposes of visit. Two-mode social networks examined the structures and positions of networks between workers and visit areas with individual attributes. RESULTS: COVID-19 risk exposure was associated with the density of dormitory, social ties, and visit areas. The migrant worker hub in the city center was the most frequently visited for essential services of grocery shopping and remittance, followed by southcentral areas mainly for social gathering. The hub was positioned as the core with the highest degree of centrality with a cluster of workers exposed to COVID-19. CONCLUSIONS: Social and geospatial networks of migrant workers should be considered in the implementation of lockdown exit strategies while addressing the improvement of living conditions and monitoring systems. Essential services, like remittance and grocery shopping at affordable prices, need to be provided near to dormitories to minimize excess gatherings. Singapore is among the biggest hit countries by the coronavirus disease 2019 (COVID- 19) pandemic. As of 15 August 2020, the city-state reported 55,661 laboratory-confirmed cases of COVID-19 in a total of 5.7 million population, the highest number of 975.8 cases per dormitories converted from disused industrial sites and other unlicensed residences. 10 Although a minimum of 4.5 square meters of "living space" per worker in PBDs is mandated, 11 nearly half breached licensing conditions every year. 12 Migrant workers are excluded from the state planning of healthcare and covered by medical insurance that employers purchase for workers under their charge, without eligibility for subsidized healthcare. 9, 13, 14 Healthcare quality is limited to meeting compliance standards of immigration procedures and occupational safety. 15 They are covered only for care for acute conditions, but not for specialized outpatient treatments, allied health (e.g., physiotherapy), rehabilitative, preventive or mental health services. 9 From the early COVID-19 outbreak, Singapore undertook a whole-of-government approach by establishing a Multi-Ministry Task Force. 16 It implemented effective measures to limit the importation of COVID-19 17 and augmented active case finding, extensive contact tracing and quarantine, testing, clinical management, and community and social measures. 16, 18 The ministry of manpower (MOM) issued advisories to dormitories on maintaining clean residential premises and promoting personal hygiene among workers. However, the monitoring system was lacking. 19 As COVID-19 continued to spread in the local community, much of the government's focus was on curbing spread among local residents. The potential risk of migrant workers' contracting COVID-19 was not given much priority. 17 and recovered workers to 'community recovery facilities' before their transition to work. 22 As of 15 August, 22,800 workers yet remained in centralized government isolation facilities. Two weeks before the end of "circuit breaker," the government laid out a three-phase approach to exit lockdown: (1) safe reopening, (2) safe transition, and (3) safe nation. 23 Accordingly, the government was set to resume construction projects with transition strategies, including regular testing to identify those with asymptomatic infection and safe distancing guidelines for workplaces and construction sites. 24 Although these strategies are essential to allow migrant workers to resume their economic roles in due time, special attention needs to be paid to nonwork-related activities of workers. The lockdown has slowed the transmission of COVID-19, yet the sustained human-to-human spread will still occur in the community. Migrant workers remain at high risk of contracting the disease if there are no guidelines to provide guidance when they engage in nonwork activities. Knowledge of the social-ecological contexts of the activities in the population is crucial to implement a wellinformed lockdown exit strategy to protect workers and prevent further spread of COVID-19. The study was designed to address the issue with its objectives to examine social and geospatial network patterns of nonwork-related activities among workers and to develop responsible and effective lockdown exit strategies for the population. A survey was conducted on 22-26 April 2020. Ethics committee approval was obtained. As in-person contacts with workers were not allowed during "circuit breaker," several recruitment strategies were employed. The study invitation flyers in English, Bengali, Tamil, and Chinese were distributed to migrant workers through NGOs. We contacted social networking sites (SNS; Facebook) run by migrant workers, who were 'SNS influencers' with a large number of migrant worker followers. With permission, the survey invitation was posted on their SNS. There were meal distribution services to dormitories. The flyers (over 300 copies) were handed with meals to workers. We also adopted a participant-driven sampling, frequently used in behavioral surveillance in hard-to-reach populations. 25 Figure S1 ). The survey measures included: (1) living conditions, (2) social ties, (3) physical and mental health, using Kessler Psychological Distress Scale, 26 and (4) COVID-19 knowledge, source of information, perceived susceptibility, self-efficacy, and COVID-19 risk exposure, assessed by whether they had infected friends. All the infected workers were transferred to isolation facilities. Thus, all survey respondents were either COVID-19 negative or not tested. Social and geospatial networks of nonwork-related activities were assessed using a grid-type measure, asking to answer the following question, "On your rest day, where do you usually go? List the places you usually went on your rest day before 'circuit breaker' based on (1) place, (2) time, (3) purpose, and (4) number of friends." up to five events (Supplementary Table S1 ). For geospatial analysis, we prepared the geographic data by generating latitude and longitude coordinates of the workers' residences and visit destinations. We categorized the 106 identified locations of visit into nine areas in a combination of the official districts and migrant worker communities to contextualize their mobility data. 27 (Supplementary Figure S2 , Table S2 ,3). The frequency of visit to each area and the density according to the following purposes were presented: (1) grocery shopping, (2) remittance, (3) social gathering, (4) outdoor leisure, (5) religious activities, (6) movie/cinema, (7) medical care, (8) dating, and (9) training. ArcGIS was used to draw the lines of mobility paths between dormitories and destinations by purposes among low-wage dormitory-dwelling migrant workers. The relations between workers and visit areas were examined using two-mode networks where workers were linked to each other through the places they visited. 28 To identify the most influential areas in the network, three key centrality metrics were calculated: (1) degree (the number of workers connected to each area); (2) closeness (how close each place node is to the other nodes based on the number of ties separating the nodes); (3) betweenness (how frequently a place node lies on the shortest path between two nodes). 29 UCINET was used for network analysis and NetDraw for visualization. The nodes of visit areas were arranged to reflect their approximate locations on the Singapore map and geographical proximity. The worker nodes were colored according to various attributes to determine if individual characteristics influence where workers visited, and by extension, their susceptibility to infection. Forty percent of workers were from 35 PBDs out of a total of 43 PBDs (coverage rate: 81.4%). Figure 1 shows the location of PBDs by isolation and recruitment. [ Figure 1 ] The majority were aged between 20-40 years old (90%), from Southeast Asia (91%), completed at least secondary education (83%), and worked in construction (76%) and shipyard (11%). The mean number of work years in Singapore, work hours per day, and rest days per month were seven years, 10 hours, and three days, respectively. The mean monthly Supplementary Table S5-7) . The majority (90%) reported correct knowledge of COVID-19 and measures of protection. Most (84%) actively sought for COVID-19 information, and 74% responded to having sufficient information. The sources of the information included SNS (83%), government notices (78%), friends and co-workers (60%), news media from Singapore (52%), and home (52%) countries. Two-thirds (65%) were worried about getting infected in the past week, 47% responded that they would likely to be infected in the next one month, and 25% didn't feel confident in COVID-19 protection and prevention of spread to others. About a quarter (24%) had at least one infected friend. The level of COVID-19 exposure was associated with residence type and density, social ties, and visit to the migrant worker hub (MW hub). (See Supplementary Table S4-7 for the comparisons) . The top three purposes were social gathering (34%), grocery shopping (34%), and remittance (32%), followed by religious activities (14%), outdoor leisure (13%), medical care (2%). (Supplementary Table S8 ). Figure 2 presents the frequency and density of visits for the three primary purposes: essential services of grocery, remittance, and nonessential activities of social gathering. While PBDs are located remotely across the island, the visit areas with more frequency were concentrated in the city center, in particular, the MW hub for essential services. Southcentral area was mainly for social gatherings. [ Figure 2 ] As seen in Figure 3 , the most frequented destinations fell into three categories: (1) the MW hub, (2) public areas on the coast (e.g., parks) throughout the island, and (3) [ Figure 3 ] The MW hub was positioned as the core in the network with the highest degree, closeness, and betweenness, which was followed by southcentral and east ( Figure 4 ). Most workers were connected through the core. The visit areas near PBDs are positioned at the peripheral. [ Figure 4 ] The networks were explored with individual attributes of social ties, having a grocery market nearby, and having a friend(s) with COVID-19 ( Figure 5; Supplementary Figure S4 ). Migrant workers who reported lower social ties with friends were more seen at the peripheries with 10 lower degrees of centrality like west, southwest, northcentral, and northwest areas. A similar pattern was found in the social network of having a local friend(s). Areas with a high degree of centrality were associated with increasing social ties. At peripheral areas like west, southwest, and northwest, migrant workers who had a supermarket nearby did not visit the MW hub. Figure 5(d) shows the cluster of migrant workers who had a friend(s) infected with COVID-19 linked to at the core. [ Figure 5 ] The for the visit, we found from the workers, is that the supermarkets in dormitories are more expensive than those in the hub. Implementing mobility restriction as a measure to reduce community transmission is only possible when their needs can be met without mobility. It is possible to impose mobility restrictions if supermarkets in closer proximity provide more affordable products. In peripheral areas like west, southwest, and northwest, workers who have a supermarket nearby did not visit areas with higher degrees of centrality. Another main reason for the visit to the MW hub was remittance, which was less available than supermarkets. Provision of the essential services nearby will effectively reduce their mobility from the periphery to the core of networks. As most workers are familiar with SNS, introducing them to mobile applications for remittance can help reduce unnecessary visits. The purposes of mobility are complex and hard to control. Visiting a specific location can serve multiple purposes. Migrant workers go to the hub to buy food, send money, attend prayer sessions at mosques, meet people, and so on. Thus, venue-based confinement of the place with strong ties, like the hub, might give confusing messages and lead to increasing public mistrust if there is no evidence to support it, and their essential activities are not directly be addressed. 30 Restriction of public gathering in one venue might increase more traffic in other places that serve similar purposes. Instead, measures should focus on offering more alternative locations for essential services to disperse what is now a highly centralized network. Decentralizing essential services across the island will also address distributive justice of fair allocation of necessities for migrant workers. The finding that they had good knowledge of COVID-19 acquired from various sources, including government notices and SNS, indicated the effective health communication made to migrant workers. 6 The penetration of public health information, which was gained from the control of COVID-19, has the potential to prepare future pandemic. While the mobility restriction of migrant worker will be gradually lifted in the coming months, structural interventions are necessary to turn the emerging formal and informal health communication and response channels into well-coordinated systems so that migrant workers continue to benefit from them not only for infectious disease outbreak but also for overall health promotion and disease protection. Notably, there is a discrepancy between good knowledge and high perceived susceptibility, suggesting the need to improve self-efficacy and coping strategies with COVID-19. The discrepancy might also result from their perceived protection from the government in terms of responsible public communication with them. 6, 8 Their existing conditions also affect their perceived susceptibility. About a quarter reported chronic cold-like symptoms, which is similar to those of COVID-19, and one third experienced mild to severe distress. Easy access to mental health services will alleviate their distress and promote self-competence. It is important to recognize the importance of the MW hub as a potential avenue to strengthen protective systems and community resilience against future pandemics in the population. 24 The hub could function positively in the time of 'new normal' with a critical mass for the diffusion of innovation for health protection. 31 The highest degrees of centralities suggest the hub could play a role as 'gate-keeping' to either block the diffusion of health information or facilitate it to other regions rapidly. 32 The direction of either closure or opening will be dependent on how the public health agencies engage with the migrant worker community in the post-COVID-19 pandemic period. 3, 33 There Thus, networks between workers are unknown. Network analyses were mainly descriptive. Further research is needed to examine the mediating effects between social networks and built environments to identify intervention focal points. Importantly, social and geospatial networks were discussed mainly from the perspectives of mitigating and managing "risk." The networks also play an important role in building up resilient healthy community systems. Thus, future research should explore the protective roles of the networks among at-risk migrant workers. Our study highlights the importance of distributive justice concerning the equal allocation of essential services, including healthcare and living necessities, for low-wage dormitorydwelling migrant workers, who are disproportionately affected by COVID-19 largely due to high-density and unhygienic built environment. Exclusionary healthcare policies put the responsibility of providing for migrant worker's health needs to the employers, and thereby limit the access to preventive health services and increase the risk of developing health adversities. 9 In efforts to address the structural barrier and to contain the spread of COVID-19 among migrant workers, Singapore's multi-ministry task force has made significant efforts by increasing geographic accessibility to testing and treatment facilities, 16, 34 which is a key to controlling the epidemic. 35 Such a multi-sectoral response system involving the Ministry of Manpower and the Ministry of Health should continue to provide migrant workers with coordinated care in the time of post-pandemic. 36 Globally, the COVID-19 pandemic has unmasked health inequity and shed light on the complex pathways from social-economic exclusion to infection of the disease in the diverse populations of low-wage migrant workers, racial and ethnic minorities, refugees, and other marginalized people with residential instability. [37] [38] [39] Individuals from lower socioeconomic strata often are 'essential workers' with pre-existing health conditions and have to continue working during lockdowns; they were thus at higher risk of exposure, and hence disease, including deaths than the general population. 40 While the risk factors of adverse health outcomes are context-specific and epi-historical dependent, the literature evidences structural causes of health disparitieslack of legal, social, and health protection in inadequate living conditionsand calls for accountability in global health justice. 8, 38 Although the COVID-19 pandemic has thrown the world into disarray, it presents us an This research was supported by the NUHS Special COVID-19 Grant, NUS Start-Up Grant, and COVID-19 National Effort Fund. The authors have declared no conflicts of interest Ministry of Health Singapore. 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All dormitories declared cleared of COVID-19 Geographic access to United States SARS-CoV-2 testing sites highlights healthcare disparities and may bias transmission estimates Health challenges in refugee resettlement: An innovative multi-sector partnership to improve the continuum of care for resettled refugees The long journey inside immigration detention centers in the U.S COVID-19: Exposing and addressing health disparities among ethnic minorities and migrants Assessing differential impacts of COVID-19 on Black communities Hospitalization and mortality among Black patients and White patients with COVID-19 We thank the migrant workers who participated in this research for their time. We thank the staff members and volunteers at HealthServe, who worked to enhance the well-being of migrant workers. We especially thank Jeffrey Chua and Michael Cheah at HealthServe for providing valuable suggestions for this project and insightful feedback on this paper. We also thank TWC2 (Transient Workers Count Too) that helped the distribution of the study invitation flyers to migrant worker dormitories.