Human challenge studies in the study of infectious diseases
What can deliberately infecting healthy people tell us about infectious diseases? How is this useful for developing treatments, and how do we manage the risks?
During the first 6 months of the pandemic, people from ethnic minority groups were more likely to have COVID-19 disease and also more likely to experience severe outcomes from infection, including death. Lockdown measures have also disproportionately affected some communities more than others. What is driving this increased prevalence and death rates in ethnic minority groups? To what extent is it due to biology or pre-existing health? Or does it represent a continuation and exacerbation of social inequalities?
DOI: https://doi.org/10.58248/RR06
A large body of research has identified health disparities that have put ethnic minority groups at higher risk of contracting and experiencing adverse consequences of COVID-19. Initial evidence suggests differences between ethnic minority groups in their experience of COVID-19.
These differences are attributed to socio-economic disadvantage, manifesting in factors such as greater exposure to infection, higher prevalence of health vulnerability and increased likelihood of losing income.
Current evidence in this area has been produced in rapid response to an ongoing situation and is often not peer-reviewed. Often, the lack of comprehensive ethnicity data can mean that the full impact of COVID-19 on different communities is unknown.
The Institute for Fiscal Studies highlights that the impacts of the pandemic are not uniform across ethnicities, and aggregating all minorities together misses important differences. In particular, the Scientific Advisory Group for Emergencies (SAGE) notes considerable differences that exist within current ethnic categories such as ‘South Asian’. Where possible in the following rapid response, the specific effects on different communities are discussed separately. This evidence summary has preserved the terminology used in the original source to ensure consistent reporting.
In addition, it is difficult to compare the overall degree of risk between different ethnic minority groups, as the risk factors and effects of COVID-19 are intersectional. Often, people from ethnic minority groups are disproportionately impacted by multiple and inter-relating factors. For example, people from some minority ethnic groups may be more likely to have an underlying health condition and more likely to work in a job with higher occupational risk.
Many reports (including by Public Health England) have found that ethnic minority groups have the highest age standardised COVID-19 diagnosis rates, whilst White ethnic groups have the lowest. Between 28 May and 26 August, Black women were over twice as likely to test positive compared with White women, and Black men were almost three times as likely to test positive compared with White men.
The Public Health England report showed that people of Chinese, Indian, Pakistani, Other Asian, Caribbean and Other Black ethnicity had between 10–50% higher risk of death compared with those of White ethnicity when other factors (such as age, deprivation and region) were controlled for.
The Runnymede Trust, a UK-based think-tank for racial inequality, found that 1 in 20 people from Black and ethnic minority groups have been hospitalised with the virus, compared with 1 in 100 White people. Hospital admissions data of the first 35,000 admitted patients indicates that critical care admission was more common in those from Black (36%), South Asian (28%) and other ethnic minority (29%) groups compared with those from White groups.
The Intensive Care National Audit and Research Centre reported that Black and ethnic minority patients account for 34% of critically ill COVID-19 patients, despite making up only 14% of the population. According to a report by Public Health England, historic racism and poorer experiences of healthcare may mean that individuals from Black and ethnic minority groups are less likely to seek care when needed, which could increase the risk of severe outcomes.
In June, the Office for National Statistics released data suggesting that Black men were over three times more likely to die from a COVID-19-related death compared with White men, and two and a half times more likely in women.
The Institute for Fiscal Studies noted that unequal rates of death among ethnic minority groups are even more stark when age is taken into account. Most ethnic minority groups have a younger average age compared with the overall UK population, which should mean they are less vulnerable and should be experiencing lower (not higher) fatality rates than average.
Researchers are conducting investigations into whether genetic components can make people more susceptible to the serious health consequences of COVID-19. However, the role of ethnicity in genetic susceptibility to viruses is highly controversial, and there is very little evidence that the disproportionate effects of COVID-19 on different ethnic minority groups have anything to do with genetics.
Instead, any existing links are more likely to be a consequence of pre-existing health inequalities, which refer to unfair and avoidable differences in health between different groups within society.
Some scientists suggest that the effects could partially be attributed to genetic variants that play a role in the body’s immune responses. Recent evidence has found that some variants affect how the body initially responds to the virus. However, there was no relationship between these variants and ethnicity.
Early research has been conducted to investigate whether vitamin D can prevent or help to treat COVID-19. The body produces vitamin D more slowly in people with darker skin, so it is possible that some ethnic minority groups are more vulnerable to COVID-19 through vitamin D deficiency. However, the National Institute for Health and Care Excellence (NICE) has concluded that there is no evidence of an effect of vitamin D levels on susceptibility to COVID-19 once other factors (such as other health conditions, social or demographic factors, and body mass index) have been accounted for.
There are also established differences in how people’s bodies respond to certain drugs, which have been shown to vary across ethnicities. These include drugs that affect ACE2 (the protein that enables coronaviruses to invade cells and replicate). However, recent studies have found that taking drugs that affect ACE2 has no impact on susceptibility from COVID-19. These drugs are often taken for pre-existing conditions such as hypertension and diabetes, which increase the risk of the severe COVID-19 outcomes. Therefore, this may be driving the perceived link between ACE2 and COVID-19.
Ethnicity is linked to the likelihood of having pre-existing conditions that increase the risk of disease severity. Compared with White British individuals over 60 years of age, people from Bangladeshi backgrounds are over 60% more likely to have a long-term health condition that makes them vulnerable to COVID-19.
People from a South Asian background (including Indian, Pakistani, Bangladeshi or Sri Lankan) are more likely to develop coronary heart disease than White Europeans. People from an African or African Caribbean background are at a higher risk of developing high blood pressure. All of the above groups more commonly have Type 2 diabetes than other ethnic groups.
A study of 35,000 hospital admissions in England, Scotland and Wales found that mortality rates were 20% higher in patients from a South Asian background compared with White patients, despite the patients admitted to hospital being 12 years younger on average. This was partially explained by a higher prevalence of diabetes.
A rapid review by Public Health England found that 10.8% of COVID-19 related death certificates mentioned end-stage organ failure (such as kidney disease). These rates were substantially higher in Black (18%) and Asian (16%) fatalities
The increased likelihood of pre-existing health conditions across ethnic minority groups is most likely due to health and social inequalities. It is likely that health inequalities have also led to a higher prevalence of smoking and obesity, which also present greater health risks to the severity of COVID-19.
Commentators, including the United Nations and Dr Omar Khan (former director of the race equality think-tank Runnymede Trust), have suggested that COVID-19 does not itself discriminate but does expose existing inequalities within society.
Many stakeholders (including the Mayor of London and The Health Foundation) have advised that the virus is not a “great leveller” as the consequences are not the same for everyone. In addition, COVID-19 and measures related to it may widen social inequalities further.
Almost all ethnic minority groups are more likely to live in urban and deprived areas, which have been most affected by COVID-19. For example, people of Pakistani ethnicity are over three times as likely to live in the most overall deprived 10% of neighbourhoods compared with those of White British ethnicity.
Researchers have suggested that these areas may have higher rates of infection because people are living in close proximity and/or with reduced healthcare access.
There is evidence that people from ethnic minority groups are more likely to live in inner-city areas that are more polluted. According to a study by Imperial College London, the worst air pollution levels were seen in ethnically diverse neighbourhoods, defined as those where more than 20% of the population were non-White.
The Office for National Statistics identified air pollution as a potential contributing factor to the disparity of COVID-19 outcomes, as it can cause breathing difficulties and other long-term conditions in the lungs and the heart.
A recent study of 400 COVID-19 patients admitted to a Birmingham hospital noted that BAME patients were more likely to be admitted from regions of higher air pollution and lower housing quality.
A recent academic study found that those from ethnic minority groups and larger households had an increased likelihood of testing positive for COVID-19. The Runnymede Trust also identified how over-crowding and multi-generational housing challenges can make it difficult for ethnic minority communities to shield or self-isolate effectively. UK Government statistics show that the highest rates of overcrowding are in Bangladeshi (24%), Pakistani (18%), Black African (16%), Arab (15%) and Mixed White and Black African (14%) background households. In comparison, only 2% of White British households are classified as over-crowded.
COVID-19 disparities between different ethnic minority groups may be due to reduced access to healthcare. Analyses by the Institute for Public Policy Research indicate that the ten most deprived authorities in England (including Birmingham, Hackney and Nottingham) have experienced 15% of all public health budget cuts in the past 5 years. According to census data, many of these areas are more ethnically diverse than the population average.
A report by the Runnymede Trust found that key government public health messaging, such as ‘Stay Home, Save the NHS, Save Lives’ was not reaching all ethnic minority communities. This may be partially attributed to language barriers for those who speak English as a second language. The BBC Asian Network published health advice explaining what COVID-19 is and how people can protect themselves, as well as information about staying healthy during Ramadan. The videos were produced in seven South Asian languages, including Hindi, Urdu and Tamil.
Coronavirus explained in Punjabi by @Dilsher10. Are your family still confused about what they can or can’t do during the coronavirus lockdown?
Look out for our other explainers in Hindi, Tamil, Gujarati, Urdu, Sylheti and Bengali. pic.twitter.com/zk6gtDo1m0
— BBC Asian Network (@bbcasiannetwork) April 15, 2020
Evidence also shows a lack of cultural competence in healthcare provision, and stakeholders suggest that the delivery of public messaging should be reconsidered to ensure it reaches all communities, particularly the communities that are most at risk.
The Independent Scientific Pandemic Influenza Group on Behaviours (SPI-B) has released guidance on public health messaging, which includes translating into a range of suitable languages and using audio files or animations to cater for reading difficulty. They also advise local authorities to actively engage with the community to produce culturally diverse messaging and to establish themselves as a trusted source of communication.
Research suggests that individuals from Black and ethnic minority groups are more likely to have had to work outside of their home during the national lockdown, and are more likely to work in occupations with a higher risk of COVID-19 exposure, such as health and social care. For example, 41% of people of African origin were estimated to be working outside of their home during lockdown, compared with 27% of White workers.
In addition, those from Chinese, Indian, Pakistani, Bangladeshi, Black African and Black Caribbean backgrounds were over twice as likely to use public transportation to travel to work compared with people from a White background.
Ethnic minority groups are over-represented in front-line healthcare worker roles and appear to have been disproportionately affected by COVID-19 compared with their White colleagues.
Healthcare staff from Black and ethnic minority groups were less likely to be able to access personal protective equipment (PPE), less likely to receive PPE training and less likely to speak up about PPE-related concerns compared with their White colleagues.
According to The Runnymede Trust, people from Bangladeshi (43%) and Black African groups (38%) were most likely to report loss of income since COVID-19, compared with 22% of White people. Those from Black and ethnic minority groups were also more likely to have used savings for day-to-day spending (14%) compared with those from White British backgrounds (8%).
The Institute for Fiscal Studies reports that, compared with White British men, Bangladeshi men were four times more likely to have jobs in industries forced to close during lockdown. Pakistani men were almost three times as likely and Black men were 50% more likely. The report suggests that this is partially due to a high concentration of workers from Asian backgrounds in certain occupations, such as the restaurant sector and taxi driving.
The IFS data also demonstrate household differences that may lead to greater financial insecurity. According to the IFS, 29% of Bangladeshi men work in a sector that was forced to close during lockdown and have a partner who is not in paid work. This compares with only 1% of White British men.
In addition, some ethnic minority groups may have been more affected by financial uncertainty due to self-employment. For example, Pakistani men are over 70% more likely to be self-employed compared with White British men. Surveys conducted by The Ubele Initiative in April predicted that nine out of ten small businesses owned by somebody from a BAME background could face permanent closure if the national lockdown lasted longer than 3 months.
According to The Runnymede Trust, people from ethnic minority groups were less likely to know about changes to financial support as a result of COVID-19, including the furlough scheme, new allowances around universal credit and claiming statutory sick pay while self-isolating. For example, their survey found that 93% of White British residents were aware of these options, compared with 61% of people from Bangladeshi backgrounds. This is likely to be attributed to wider existing social inequalities and suggests that people from ethnic minority groups face greater barriers when accessing information or support.
SPI-B also reported that ethnic minority residents may be particularly vulnerable to the effects of local restrictions. Local lockdowns are more likely to be implemented in densely populated urban areas, which have higher rates of ethnic diversity. The disproportionate economic and social burden for the people living in those areas means that lockdowns have the potential to increase inequalities.
Further, evidence suggests that lockdowns have limited benefit for those who have had to continue working outside of the home, or for those living in multi-occupancy and multi-generational households. As a result, people from ethnic minority groups may be less likely to be protected by lockdowns but more likely to experience subsequent disadvantages.
Scientific advisers have observed that local lockdowns may cause racial tensions and risks to social cohesion, particularly when local lockdowns are perceived to map onto particular ethnic minority communities or do not take into account cultural or religious factors.
Local lockdowns can increase the risk of racial stigmatisation and discrimination. Those infected may be identified along with close contacts, which can result in them and their networks being blamed for the impact of COVID-19. This makes ethnic minority groups more vulnerable, as they are more likely to test positive for COVID-19.
Frontline healthcare workers, of which ethnic minority groups are over-represented, have been assaulted and denied services (such as transport) due to fear that they may pass on the virus. Media reports have suggested that people from a Chinese background have fallen victim to racist attacks due to the virus originating in China.
A survey by The Runnymede Trust found that 14% of adults in Britain reported that “social isolation is making relationships at home more difficult than usual”. This figure was higher within ethnic minority groups, at nearly one in five.
One in five White British respondents reported no impact of childcare or home-schooling, compared with one in twenty Pakistani and one in ten Bangladeshi and Indian respondents. Over half of Chinese, Indian and Black African groups reported struggling with more than two issues related to balancing work, childcare, home-schooling and shopping. This is also likely to have been exacerbated by the impact of lockdown on existing social inequalities, such as living in crowded housing or areas with limited green space.
The Royal College of Paediatrics and Child Health has reported increased mental strain for young people, particularly those from Pakistani, Bangladeshi and Black backgrounds, as they are more likely to lose a loved one and less likely to be able to access education remotely.
Kooth, a digital mental health service for children and young people commissioned by the NHS, has released a report based on data from over 75,000 users aged 11–25 years. Self-reported depression increased by 9.2% in children and young people from ethnic minority backgrounds during lockdown, compared with a 16.2% decrease in reports from White children and young people.
The NHS Confederation is in the process of setting up The NHS Race and Health Observatory, a new independent body that will offer analysis and policy recommendations to improve health outcomes for NHS patients, communities and staff from ethnic minority groups. This was announced following the 2019 NHS Workforce Equality Standard Report which highlighted racial discrimination within the NHS.
Following their West Midlands Inquiry into COVID-19 fatalities in ethnic minority groups, Labour MPs and councillors have published recommendations to better understand how different ethnic minority groups are affected and to mitigate the consequences. Recommendations include ensuring that death certificates record ethnicity (which has been standard in Scotland for 10 years but is not yet standard across the whole of the UK) and ensuring that within the next 12–18 months health and care system leadership changes to reflect the diversity of the community it serves.
Research funding bodies UK Research and Innovation (UKRI) and the National Institute for Health Research (NIHR) have announced £4.3 million worth of funding into six projects to explain and mitigate the disproportionate COVID-19 death rate across different ethnic minority groups. Research organisations are also actively working to improve the ethnic diversity in research participant recruitment for studies around COVID-19.
Some existing longitudinal initiatives can help better understand the impact of ethnicity on health and well-being. For example, a number of funding agencies and the NHS are collaborating on the ‘Born In Bradford’ study, which is tracking the health of 13,000 children born between 2007–2010. The study considers ethnicity alongside other factors to investigate how health and well-being can be improved in a diverse population.
Public Health England has published an evidence review, ‘Beyond the data: Understanding the impact of COVID-19 on BAME groups’. The report suggests that the UK Government should ensure COVID-19 recovery strategies reduce existing health inequalities. This contains a series of recommendations, including improving comprehensive ethnicity data collection, delivering targeted programmes for chronic disease prevention, and developing culturally competent public health information and occupational risk assessment. For the latter to be successful, the report highlights the evidence-based need for stakeholder and community engagement from people of Black, Asian and ethnic minority groups.
In June, the Scottish Government announced a new Expert Reference Group which will investigate the impact of COVID-19 on ethnic minority groups. The group (consisting of academics, advisers and government officials) will consider evidence and data being gathered by the Scottish Government, Public Health Scotland, National Records of Scotland and NHS Scotland, and advise on policy actions to mitigate any disproportionate effects.
In April, the Welsh Government established the COVID-19 BAME Advisory Group, which has conducted an inquiry and made over 30 recommendations to the Welsh Government. Public Health Wales has also produced a summary of the data.
The Public Health Agency in Northern Ireland is supporting a UK-wide inquiry and has published guidance on how BAME workers can be supported within the workplace.
SAGE considered a paper prepared by their ethnicity sub-group on the drivers of the higher COVID-19 incidence, morbidity and mortality among minority ethnic groups on 24 September 2020.
Thank you to the following external reviewers for their time and comments:
Dr Shivani Sharma, University of Hertfordshire
Dr Manish Pareek, University of Leicester
Dr Natalie Darko, University of Leicester
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