Prisoners are over three times more likely to die with the coronavirus than a member of the public, research suggests.
Outbreaks emerged in the facilities early in the pandemic, prompting prison officials to ban family visits and impose strict social distancing measures, with some inmates forced to stay in their cell for 23 hours a day.
Scientists from University College London (UCL) have since reported 121 coronavirus-related deaths occurred among inmates in England and Wales from March 2020 to February 2021.
This represents a 3.3 times higher fatality risk than people of the same age and sex outside of confinement.
Institutional settings are high-risk environments for infectious disease outbreaks due to them typically being overcrowded, with "inconsistent access" to hand washing facilities, according to the scientists.
Off the back of their results, the team hopes prisoners will be prioritised for a coronavirus vaccine, regardless of their age or underlying health.
"Our findings show people in prisons are at a much higher risk of dying from COVID-19 [the disease caused by the coronavirus] than the general population, and we make the case both they and prison staff should be given high priority in the rollout of vaccines," said lead author Dr Isobel Braithwaite.
"This has recently been agreed for people experiencing homelessness, who face similarly high risks.
"We believe the current methods of regime restriction are not enough to protect people adequately, and a systematic, 'whole-prison' approach to vaccination is key to preventing further outbreaks and reducing overall deaths in prisons."
As well as coronavirus deaths being higher among inmates, prisoners were also found to be more at risk of catching the infection in the first place.
The scientists found 7.6 confirmed coronavirus cases occurred per 1,000 prisoners in England and Wales during the first pandemic wave.
This is compared to just 4.9 incidences per 1,000 people among the general public.
In January 2021 alone, when anti-infection measures should have been well established, 85% of prison or youth custody services reported coronavirus cases, with more than 4,000 new incidences between them.
Some of these outbreaks led to hundreds of cases in just one centre.
Prison staff may have also been disproportionately affected by the coronavirus.
The UCL scientists flagged a recent tweet by the Prison Officers' Association that revealed 20 members of staff had died up to mid-January 2021, while 4,800 employees had isolated with the infection – more than 10% of the workforce.
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As well as prisons being considered an at-risk environment, inmates often have underlying health issues or other risk factors that predispose them to coronavirus complications, according to the scientists.
Studies have suggested asthma and high blood pressure are common among prisoners. Many also have a history of smoking, "which increases risks from COVID-19 through multiple pathways".
Prison inmates and staff are being offered a coronavirus vaccine in line with the general prioritisation criteria, based on the individual's age and any long-term medical condition.
The UCL scientists argue identifying eligible inmates can be difficult due to previous medical information often being absent and prisoners not always engaging with healthcare services.
An inmate may therefore be considered low priority "by default", they added.
A recent survey by the peer support organisation Empowering People: Inspiring Change found just under four in five (78%) prisoners would accept a coronavirus vaccine if offered a jab.
"At the moment, vaccinating the small numbers of people in any specific risk group in a single prison risks leftover doses and possible wastage of vaccine, and isn't happening fast enough to protect either people in prison or prison staff," said co-author Dr Jake Hard, from the Royal College of GPs.
"We believe simultaneous vaccination of whole prison populations, including staff, is vital and could help alleviate mistrust, increase uptake and speed up recovery.
"A change of approach is urgently needed to help prevent further outbreaks in prisons and to ensure that the unacceptable higher rate of death we found in our study doesn’t continue."
Without a "whole-prison approach", the centres will not achieve a "good level of protection", which prevents family visits and rehabilitation activities from restarting until late in the vaccine programme roll-out.
"Prisons are struggling after repeated prison lockdowns and restricted regimes," the scientists wrote in The Lancet Respiratory Medicine.
"Some prisoners have been awaiting trial in these conditions.
"The prolonged isolation and separation from families would, under normal circumstances, breach human rights.
"With vaccination now possible, these conditions can no longer be accepted."
As the UK's coronavirus restrictions gradually ease, inmates may face a higher risk of infection via outings like court visits.
"Early whole-institution vaccination can prevent outbreaks, ensure the basic rights of people in prisons, and protect staff and the wider community," wrote the scientists.
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