diff --git a/content/40.inequality.md b/content/40.inequality.md index 4edff7963..2b60c6f04 100644 --- a/content/40.inequality.md +++ b/content/40.inequality.md @@ -1,5 +1,9 @@ ## Social Factors Influencing COVID-19 Exposure and Outcomes +### Abstract + +### Importance + ### Social Factors Influencing COVID-19 Outcomes In addition to understanding the fundamental biology of the SARS-CoV-2 virus and COVID-19, it is critical to consider how the broader environment can influence both COVID-19 outcomes and efforts to develop and implement treatments for the disease. @@ -7,7 +11,7 @@ The evidence clearly indicates that social environmental factors are critical de There are distinct components to COVID-19 susceptibility, and an individual's risk can be elevated at one or all stages from exposure to recovery/mortality: an individual may be more likely to be exposed to the virus, more likely to get infected once exposed, more likely to have serious complications once infected, and be less likely to receive adequate care once they are seriously ill. The fact that differences in survival between Black and white patients were no longer significant after controlling for comorbidities and socioeconomic status (type of insurance, neighborhood deprivation score, and hospital where treatment was received) in addition to sex and age [@doi:10.1001/jamanetworkopen.2020.18039] underscores the relevance of social factors to understanding mortality differences between racial and ethnic groups. Moreover, the Black patients were younger and more likely to be female than white patients, yet still had a higher mortality rate without correction for the other variables [@doi:10.1001/jamanetworkopen.2020.18039]. -Here, we outline a few systemic reasons that may exacerbate the COVID-19 pandemic in communities of color. +Here, we outline some of the systemic reasons that may exacerbate the COVID-19 pandemic in communities of color. ### Factors Observed to be Associated with Susceptibility @@ -27,9 +31,9 @@ Some are intrinsic characteristics that have been observed to carry an associati Two traits that have been consistently associated with more severe COVID-19 outcomes are male sex and advanced age (typically defined as 60 or older, with the greatest risk among those 85 and older [@url:https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/older-adults.html]). In the United States, males and older individuals diagnosed with COVID-19 were found to be more likely to require hospitalization [@doi:10.1377/hlthaff.2020.00598; @doi:10.15585/mmwr.mm6925e1]. A retrospective study of hospitalized Chinese patients [@doi:10/ggnxb3] found that a higher probability of mortality was associated with older age, and world-wide, population age structure has been found to be an important variable for explaining differences in outbreak severity [@doi:10.1073/pnas.2004911117]. -The CFR for adults over 80 has been estimated upwards of 14% or even 20% [@doi:10.1111/jgs.16472]. +The case fatality rate (CFR) for adults over 80 has been estimated upwards of 14% or even 20% [@doi:10.1111/jgs.16472]. Male sex has also been identified as a risk factor for severe COVID-19 outcomes, including death [@doi:10.1136/bmj.m1985; @doi:10.1186/s13293-020-00304-9; @url:https://globalhealth5050.org/the-sex-gender-and-covid-19-project/]. -Early reports from China and Europe indicated that even though the case rates were similar across males and females, males were at elevated risk for hospital admission, ICU admission, and death [@doi:10.1186/s13293-020-00304-9], although data from some US states indicates more cases among females, potentially due to gender representation in care-taking professions [@doi:10.1371/journal.ppat.1008570]. +Early reports from China and Europe indicated that even though the case rates were similar across males and females, males were at elevated risk for hospital admission, ICU admission, and death [@doi:10.1186/s13293-020-00304-9], although data from some U.S. states indicates more cases among females, potentially due to gender representation in care-taking professions [@doi:10.1371/journal.ppat.1008570]. In older age groups (e.g., age 60 and older), comparable absolute numbers of male and female cases actually suggests a higher rate of occurrence in males, due to increased skew in the sex ratio [@doi:10.1186/s13293-020-00304-9]. Current estimates based on worldwide data suggest that, compared to females, males may be 30% more likely to be hospitalized, 80% more likely to be admitted to the ICU, and 40% more likely to die as a result of COVID-19 [@url:https://globalhealth5050.org/the-sex-gender-and-covid-19-project/]. There also may be a compounding effect of advanced age and male sex, with differences time to recovery worst for males over 60 years old relative to female members of their age cohort [@doi:10.1371/journal.ppat.1008520]. @@ -42,27 +46,29 @@ ACE2 expression in the kidneys of male mice was observed to be twice as high as Other work in mice has shown an inverse association between mortality due to SARS-CoV-1 and estradiol, suggesting a protective role for the sex hormone [@doi:10.1371/journal.ppat.1008570]. Similarly, evidence suggests that similar patterns might be found in other tissues. A preliminary analysis identified higher levels of ACE2 expression in the myocardium of male patients with aortic valve stenosis showed than female patients, although this pattern was not found in controls [@doi:10.1186/s13293-020-00304-9]. -Additionally, research has indicated that females respond to lower doses than males of heart medications that act on the Renin angiotensin aldosterone system (RAAS) pathway, which is shared with ACE2 [@doi:10.1186/s13293-020-00304-9]. -Additionally, several components of the immune response, including the inflammatory response, may differ in intensity and timing between males and females [@doi:10.1371/journal.ppat.1008570; @doi:10.1186/2042-6410-1-6]. -This hypothesis is supported by some preliminary evidence showing that female patients who recovered from severe COVID-19 had higher antibody titers than males [@doi:10.1371/journal.ppat.1008570]. +Additionally, research has indicated that females respond to lower doses than males of heart medications that act on the renin angiotensin aldosterone system (RAAS) pathway than males, which is shared with ACE2 [@doi:10.1186/s13293-020-00304-9]. +Furthermore, several components of the immune response, including the inflammatory response, may differ in intensity and timing between males and females [@doi:10.1371/journal.ppat.1008570; @doi:10.1186/2042-6410-1-6]. +This hypothesis is supported by some preliminary evidence showing that female patients who recovered from severe COVID-19 had higher antibody titers than males [@doi:10.1371/journal.ppat.1008570; @doi:10.1002/jmv.25989]. Sex steroids can also bind to immune cell receptors to influence cytokine production [@doi:10.1186/s13293-020-00304-9]. Additionally, social factors may influence risks related to both age and sex: for example, older adults are more likely to live in care facilities, which have been a source for a large number of outbreaks [@doi:10.1093/qjmed/hcaa136], and gender roles may also influence exposure and/or susceptibility due to differences in care-taking and/or risky behaviors (e.g., caring for elder relatives and smoking, respectively) [@doi:10.1186/s13293-020-00304-9] among men and women (however, it should be noted that both transgender men and women are suspected to be at heightened risk [@url:https://escholarship.org/uc/item/55t297mc].) #### Comorbid Health Conditions A number of pre-existing or comorbid conditions have repeatedly been identified as risk factors for more severe COVID-19 outcomes. -Several underlying health conditions were identified at high prevalence among hospitalized patients, including obesity, diabetes, hypertension, lung disease, and cardiovascular disease [@doi:10.15585/mmwr.mm6915e3]. -Higher Sequential Organ Failure Assessment (SOFA) scores have been associated with a higher probability of mortality [@doi:10/ggnxb3], and comorbid conditions such as cardiovascular and lung disease as well as obesity were also associated with an increased risk of hospitalization and death, even when correcting for age and sex [@doi:10.1136/bmj.m1985]. +Several underlying health conditions were identified at high prevalence among hospitalized patients, including obesity, diabetes, hypertension, lung disease, cerebrovascular disease, and cardiovascular disease [@doi:10.15585/mmwr.mm6915e3;@doi:10.18632/aging.103000]. +Higher sequential organ failure assessment (SOFA) scores have been associated with a higher probability of mortality [@doi:10/ggnxb3], and comorbid conditions such as cardiovascular and lung disease as well as obesity were also associated with an increased risk of hospitalization and death, even when correcting for age and sex [@doi:10.1136/bmj.m1985]. Diabetes may increase the risk of lengthy hospitalization [@doi:10.1016/j.cmet.2020.04.021] or of death [@doi:10.1016/j.cmet.2020.04.021;@doi:10.1007/s00592-020-01546-0]. [@doi:10.1111/dom.14057] and [@doi:10.1152/ajpendo.00124.2020] discuss possible ways in which COVID-19 and diabetes may interact. Obesity also appears to be associated with higher risk of severe outcomes from SARS-CoV-2 [@doi:10.1016/j.metabol.2020.154262; @doi:10.1101/2020.04.23.20076042]. Obesity is considered an underlying risk factor for other health problems, and the mechanism for its contributions to COVID-19 hospitalization or mortality is not yet clear [@doi:10.1016/j.medj.2020.06.005]. +However, obesity was also identified as a risk factor for hospitalization of patients during the H1N1 influenza epidemic in 2009 [@doi:10.1001/jama.2009.1583; @doi:10.4065/mcp.2010.0166], thus there is a need to explore the mechanistic links between obesity and outcomes of viral respiratory infections [@doi:10.1136/thoraxjnl-2012-203009; @doi:10.1016/j.pupt.2012.04.006]. Dementia and cancer were also associated with the risk of death in an analysis of a large number (more than 20,000) COVID-19 patients in the United Kingdom [@doi:10.1136/bmj.m1985]. It should be noted that comorbid conditions are inextricably tied to age, as conditions tend to be accumulated over time, but that the prevalence of individual comorbidities or of population health overall can vary regionally [@doi:10.1073/pnas.2008760117]. Several comorbidities that are highly prevalent in older adults, such as COPD, hypertension, cardiovascular disease, and diabetes, have been associated with CFRs upwards of 8% compared to an estimate of 1.4% in people without comorbidities [@doi:10.1111/jgs.16472; @url:https://www.who.int/publications/i/item/report-of-the-who-china-joint-mission-on-coronavirus-disease-2019-(covid-19)]. Therefore, both age and health are important considerations when predicting the impact of COVID-19 on a population [@doi:10.1073/pnas.2008760117]. -However, other associations may exist, such as patients with sepsis having higher SOFA scores -- in fact, SOFA was developed for the assessment of organ failure in the context of sepsis, and the acronym originally stood for Sepsis-Related Organ Failure Assessment [@doi:10.1007/BF01709751; @doi:10.1001/jama.2016.0287]. -Additionally, certain conditions are likely to be more prevalent under or exacerbated by social conditions, especially poverty, as is discussed further below. +However, other associations may exist, such as patients with sepsis having higher SOFA scores -- in fact, SOFA was developed for the assessment of organ failure in the context of sepsis, and the acronym originally stood for sepsis-related organ failure assessment [@doi:10.1007/BF01709751; @doi:10.1001/jama.2016.0287]. +Indeed, vitamin D insufficiency and deficiency has also been linked to COVID-19 incidence and mortality, particularly in Black, Asian, and minority ethnic (BAME) groups [@doi:10.3390/nu13030740; @individual-nutraceuticals; @doi:10.1001/jamanetworkopen.2021.4117; @doi:10.1016/j.mayocp.2021.02.014]. +Additionally, certain conditions are likely to be more prevalent under or exacerbated by social conditions, especially poverty, and malnutrition, as is discussed further below. #### Ancestry @@ -102,22 +108,23 @@ Thus, the current evidence suggests that the apparent correlations between ances Social distancing has emerged as one of the main social policies used to manage the COVID-19 epidemic in many countries. Many governments issued stay-at-home orders, especially in the initial months of the crisis. -However, data clearly indicates that these orders impacted different socioeconomic groups differently. +However, data clearly indicates that these orders impacted socioeconomic groups differently, and thus likely affected an individual's risk of COVID-19 exposure. In U.S. counties with and without stay-at-home orders, smartphone tracking indicated a significant decrease in the general population's mobility in April relative to February through March of 2020 (-52.3% and -60.8%, respectively) [@doi:10.1101/2020.05.03.20084624]. -A linear relationship was observed between counties' reduction in mobility and their wealth and health, as measured by access to health care, food security, income, space, and other factors [@doi:10.1101/2020.05.03.20084624]. +A linear relationship was observed between counties' reduction in mobility and their wealth and health, as measured by access to healthcare, food security, income, space, and other factors [@doi:10.1101/2020.05.03.20084624]. Counties with greater reductions in mobility were also found to have much lower child poverty and household crowding and to be more racially segregated, and to have fewer youth and more elderly residents [@doi:10.1101/2020.05.03.20084624]. Similar associations between wealth and decreased mobility were observed in cellphone GPS data from Colombia, Indonesia, and Mexico collected between January and May 2020 [@arXiv:2006.15195], as well as in a very large data set from several US cities [@doi:10.1038/s41586-020-2923-3]. These disparities in mobility are likely to be related to the role that essential workers have played during the pandemic. Essential workers are disproportionately likely to be female, people of color, immigrants, and to have an income below 200% of the poverty line [@url:https://mronline.org/wp-content/uploads/2020/06/2020-04-Frontline-Workers.pdf]. -Black Americans in particular are over-represented among front-line workers and in professions where social distancing is infeasible [@doi:10.1002/ajim.23145]. -Health care work in particular presents an increased risk of exposure to SARS-CoV-2 [@doi:10.1002/ajim.23145; @doi:10.1371/journal.pone.0232452; @url:https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/causesofdeath/bulletins/coronaviruscovid19relateddeathsbyoccupationenglandandwales/deathsregistereduptoandincluding20april2020; @url:https://www.ons.gov.uk/employmentandlabourmarket/peopleinwork/employmentandemployeetypes/articles/whichoccupationshavethehighestpotentialexposuretothecoronaviruscovid19/2020-05-11; @url:https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/892085/disparities_review.pdf]. -In the United Kingdom, (South) Asians are more likely than their white counterparts to be medical professionals [@url:https://www.ifs.org.uk/inequality/chapter/are-some-ethnic-groups-more-vulnerable-to-covid-19-than-others/], although BAME medical professionals are still disproportionately represented in the proportion of National Health Service staff deaths [@url:https://www.hsj.co.uk/exclusive-deaths-of-nhs-staff-from-covid-19-analysed/7027471.article]. +Black Americans in particular are over-represented among frontline workers and in professions where social distancing is infeasible [@doi:10.1002/ajim.23145]. +Healthcare work also presents an increased risk of exposure to SARS-CoV-2 [@doi:10.1002/ajim.23145; @doi:10.1371/journal.pone.0232452; @url:https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/causesofdeath/bulletins/coronaviruscovid19relateddeathsbyoccupationenglandandwales/deathsregistereduptoandincluding20april2020; @url:https://www.ons.gov.uk/employmentandlabourmarket/peopleinwork/employmentandemployeetypes/articles/whichoccupationshavethehighestpotentialexposuretothecoronaviruscovid19/2020-05-11; @url:https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/892085/disparities_review.pdf]. +In the United Kingdom, (South) Asians are more likely than their white counterparts to be medical professionals [@url:https://www.ifs.org.uk/inequality/chapter/are-some-ethnic-groups-more-vulnerable-to-covid-19-than-others/], although BAME medical professionals are still disproportionately represented in the proportion of National Health Service (NHS) staff deaths [@url:https://www.hsj.co.uk/exclusive-deaths-of-nhs-staff-from-covid-19-analysed/7027471.article]. Similar trends have been reported for nurses, especially nurses of color, in the United States [@url:https://act.nationalnursesunited.org/page/-/files/graphics/0920_Covid19_SinsOfOmission_Data_Report.pdf]. Furthermore, beyond the risks associated with work itself, use of public transportation may also impact COVID-19 risk [@url:http://www.nber.org/papers/w27407]. The socioeconomic and racial/ethnic gaps in who is working on the front lines of the pandemic make it clear that socioeconomic privilege is likely to decrease the probability of exposure to SARS-CoV-2. +Indeed, an analysis in the U.S. reported that low socioeconomic status was associated with higher incidences of SARS-CoV-2 infection and COVID-19 mortality [@doi:10.1016/j.socscimed.2020.113554]. Increased risk of exposure can also arise outside the workplace. -Nursing homes and skilled nursing facilities received attention early on as high-risk locations for COVID-19 outbreaks [@doi:10.1001/jama.2020.11642]. +Nursing homes and skilled nursing facilities received attention early on in the pandemic as high-risk locations for COVID-19 outbreaks [@doi:10.1001/jama.2020.11642]. Prisons and detention centers also confer a high risk of exposure or infection [@doi:10.1001/jamainternmed.2020.1856; @doi:10.1001/jama.2020.12528]. Populations in care facilities are largely older adults, and in the United States, incarcerated people are more likely to be male and persons of color, especially Black [@url:https://www.issuelab.org/resources/695/695.pdf]. Additionally, multi-generational households are less common among non-Hispanic white Americans than people of other racial and ethnic backgrounds [@doi:10.1111/j.1751-9020.2010.00306.x], increasing the risk of exposure for more susceptible family members. @@ -129,7 +136,7 @@ As a result, facets of systemic inequality such as mass incarceration of Black A Following exposure to SARS-CoV-2, the likelihood that an individual develops COVID-19 and the severity of the disease presentation can be influenced by a number of social factors. As discussed above, a number of patient characteristics are associated with the likelihood of severe COVID-19 symptoms. -In some cases, these trends run counter to those expected given rates of exposure: for example, although women are more likely to be exposed, men are more likely to be diagnosed with, hospitalized from, or die from COVID-19 [@doi:10.1371/journal.ppat.1008570]. +In some cases, these trends run counter to those expected given rates of exposure: for example, although women are more likely to be exposed, men are more likely to be hospitalized with, or die from COVID-19 [@doi:10.1371/journal.ppat.1008570; @doi:10.1038/s41467-020-19741-6]. In the case of comorbid conditions and racial/ethnic demographics, however, social factors are highly likely to modulate or at least influence the apparent association between these traits and the increased risk from COVID-19. In particular, the comorbidities and racial/ethnic correlates of severe COVID-19 outcomes suggest that poverty confers additional risk for COVID-19. @@ -138,7 +145,7 @@ In particular, we focus on the United States and the United Kingdom. Comorbidities that increase risk for COVID-19, including obesity, type II diabetes, hypertension, and cardiovascular disease, are known to be intercorrelated [@doi:10/bpp37d]. Metabolic conditions related to heightened inflammation, like obesity, type II diabetes, and hypertension, are more strongly associated with negative COVID-19 outcomes than other comorbid conditions, such as chronic heart disease [@doi:10.2337/dbi19-0023]. As discussed above, dysregulated inflammation characteristic of cytokine release syndrome is one of the greatest concerns for COVID-19-related death. -Therefore, it is possible that chronic inflammation characteristic of these metabolic conditions predisposes patients to COVID-19-related death [@doi:10.2337/dbi19-0023]. +Therefore, it is possible that chronic systemic inflammation, which is characteristic of these metabolic conditions [@doi:10.1172/JCI92035], predisposes patients to COVID-19-related death [@doi:10.2337/dbi19-0023; @doi:10.2337/dc20-1714]. The association between these diseases and severe COVID-19 outcomes is a concern from a health equity perspective because poverty exposes people to "obesogenic" conditions [@doi:10/gddg84] and is therefore unsurprisingly associated with higher incidence of obesity and associated disorders [@doi:10.5604/12321966.1120608]. Furthermore, cell phone GPS data suggests that lower socioeconomic status may also be associated with decreased access to healthy food choices during the COVID-19 pandemic [@doi:10.1002/oby.22940; @doi:10.1002/oby.22993], suggesting that health-related risk factors for COVID-19 may be exacerbated as the pandemic continues [@doi:10.1016/j.pcad.2020.07.002]. Chronic inflammation is a known outcome of chronic stress (e.g., [@doi:10.1067/mai.2000.110163; @doi:10.1037/0278-6133.21.6.531; @doi:10.1037/a0025536; @doi:10.1111/j.1467-8721.2006.00450.x]). @@ -148,7 +155,9 @@ A preprint [@doi:10.1101/2020.04.05.20054502] provided observational evidence th Although lack of individual-level exposure data and the impossibility of randomization make it difficult to elucidate the exact causal mechanism, this finding would be consistent with similar findings for all-cause mortality (e.g., [@doi:10.1073/pnas.1803222115]). Exposure to air pollution is associated with both poverty (e.g., [@doi:10.3390/ijerph15061114]) and chronic inflammation [@doi:10.1016/j.neubiorev.2018.06.002]. Other outcomes of environmental racism, such as the proximity of abandoned uranium mines to Navajo land, can also cause respiratory illnesses and other health issues [@url:https://journalhosting.ucalgary.ca/index.php/jisd/article/view/70753/54416]. -Similarly, preliminary findings indicate that nutritional status (e.g., vitamin D deficiency [@doi:10.1210/clinem/dgaa733]) may be associated with COVID-19 outcomes, and reduced access to grocery stores and fresh food often co-occurs with environmental racism [@url:https://journalhosting.ucalgary.ca/index.php/jisd/article/view/70753/54416; @doi:10.1056/NEJMp2021264]. +Similarly, preliminary findings indicate that nutritional status (e.g., vitamin D deficiency [@doi:10.1210/clinem/dgaa733; @doi:10.3390/nu12041181; @doi:10.3390/nu12051466; @individual-nutraceuticals]) may be associated with COVID-19 outcomes, and reduced access to grocery stores and fresh food often co-occurs with environmental racism [@url:https://journalhosting.ucalgary.ca/index.php/jisd/article/view/70753/54416; @doi:10.1056/NEJMp2021264]. +Poverty and food insecurity may also contribute to malnutrition leading to increased risk of comorbidities, which in turn may increase one's risk for COVID-19 [@doi:10.1016/j.pcad.2020.07.002]. + Taken together, the evidence suggests that low-income workers who face greater exposure to SARS-CoV-2 due to their home or work conditions are also more likely to face environmental and social stressors associated with increased inflammation, and therefore with increased risk from COVID-19. In particular, structural racism can play an important role on disease severity after SARS-CoV-2 exposure, due to consequences of racism which include an increased likelihood of poverty and its associated food and housing instability. COVID-19 can thus be considered a "syndemic", or a synergistic interaction between several epidemics [@doi:10.1002/ajhb.23482]. @@ -198,7 +207,7 @@ Experimental treatments are often made available to patients primarily or even e The advantage of this approach is that clinical trials are designed to collect rigorous data about the effects of a treatment on patients. The disadvantage is that access to clinical trials is not equal among all people who suffer from a disease. Two important considerations that can impact an individual's access to clinical trials are geography and social perceptions of clinical trials. -For the first, the geographic distribution of trial recruitment efforts are typically bounded and can vary widely among difference locations, and for the second, the social context of medical interactions can impact strategies for and the success of outreach to different communities. +For the first, the geographic distribution of trial recruitment efforts are typically bounded and can vary widely among different locations, and for the second, the social context of medical interactions can impact strategies for and the success of outreach to different communities. Differential access to clinical trials raises concerns because it introduces biases that can influence scientific and medical research on therapeutics and prophylactics broadly. Concerns about bias in clinical trials need to address both trial recruitment and operation. In the present crisis, such biases are particularly salient because COVID-19 is a disease of global concern. @@ -226,9 +235,10 @@ First, treatments such as remdesivir that are promising but primarily available Second, it raises the concern that the findings of clinical trials will be based on participants from many of the wealthiest countries, which may lead to ambiguity in whether the findings can be extrapolated to COVID-19 patients elsewhere. Especially with the global nature of COVID-19, equitable access to therapeutics and vaccines has been a concern at the forefront of many discussions about policy (e.g., [@doi:10/ggq7mf], yet data like that shown in Figure @fig:ebm-map demonstrates that accessibility is likely to be a significant issue. Another concern with the heterogeneous international distribution of clinical trials is that the governments of countries leading these clinical trials might prioritize their own populations once vaccines are developed, causing unequal health outcomes [@doi:10.1001/jama.2020.6641]. +Indeed, Britain, Canada, and the U.S. have all reserved excess doses of vaccines from various providers to prioritize immunization of their citizens before distributing their remainders to other countries [@url:https://www.nytimes.com/2020/12/15/us/coronavirus-vaccine-doses-reserved.html] Additionally, even within a single state in the United States (Maryland), geography was found to influence the likelihood of being recruited into or enrolled in a clinical trial, with patients in under-served rural areas less likely to enroll [@doi:10.1016/j.cdp.2005.12.001]. Thus, geography both on the global and local levels may influence when treatments and vaccines are available and who is able to access them. -Efforts such as the African Union's efforts to coordinate and promote vaccine development [@doi:10/fgzk] are therefore critical to promoting equity in the COVID-19 response. +Programs such as the African Union's efforts to coordinate and promote vaccine development [@doi:10/fgzk], and the COVID-19 Vaccines Global Access (COVAX) Facility who aim to provide equitable vaccine distribution [@url:https://www.who.int/publications/m/item/fair-allocation-mechanism-for-covid-19-vaccines-through-the-covax-facility], are therefore critical to promoting equity in the COVID-19 response. Even when patients are located within the geographic recruitment area of clinical trials, however, there can still be demographic inequalities in enrollment.