Lifting lockdown measures before enough people are vaccinated is likely to cause “explosive epidemics” in vulnerable and deprived communities where less people have had the jab, scientists have told the government.

Experts from the Scientific Advisory Group for Emergencies (Sage) warned the government the vaccine rollout needs to be “well advanced” before restrictions can be relaxed.

The Scientific Pandemic Influenza Group on Modelling Operational (SPI-M-O) sub-group report – dated January 13 but only made public on Friday – states: “A further epidemic wave will take place if non-pharmaceutical interventions start being lifted before vaccine rollout is well advanced.”

The group adds that, if that were to happen, “transmission would be highest in the most vulnerable, deprived communities with lowest vaccination coverage, likely leading to explosive epidemics”.

A total of 7,263,317 Covid-19 vaccinations had taken place in England as of January 28, according to provisional NHS data. That’s more than one in nine of the adult population.

Over 80% of people aged over 80 have had the jab, as have over two thirds of elderly care home residents.

But preliminary data published this week suggests older adults from ethnic minority groups, those with severe mental illness or learning disabilities, and those from deprived areas are less likely to have received a vaccine – the same groups SPI-M-O experts warned would be hit hardest.

The Office for National Statistics has found all ethnic minority groups, other than people from Chinese backgrounds, are more likely to die from the virus than white people.

The paper, not yet peer reviewed, is believed to be the first detailed study of the demographic and clinical characteristics of people vaccinated in England.

The authors, from the University of Oxford, the London School of Hygiene and Tropical Medicine and the healthcare technology company TPP, do say their findings should be interpreted with caution. That’s because the data is from the initial weeks of the “rapidly evolving” rollout and the authors say there will be many drivers behind the varying rates.

They analysed data covering 23.4m people registered with GP surgeries using the OpenSAFELY-TPP platform for electronic health records, which covers approximately 40% of the general population in England.

Some 961,580 people had received their first Covid-19 jab between December 8 and January 13.

Of the 1,160,062 people aged 80 and over and not living in a care home covered by the dataset, 476,375 had received a vaccine – around 41%.

But the study found 42.5% of the 788,806 white people in this group had been vaccinated, compared with just 20.5% of the 10,329 Black people.

Between 27.0% to 29.5% of people of mixed, other and South Asian ethnicities over 80 had received a vaccine, and 39.7% of those with unknown ethnicity.

The researchers also found that 44.7% of people over 80 in the least deprived areas had been given a vaccine, compared with 37.9% of those in the most deprived areas.

Elderly patients with pre-existing medical conditions were equally likely to have received a vaccine as those without such conditions, which the authors called “reassuring”. But there were exceptions, with 30.3% of people with severe mental illness having received a vaccine, 30.9% of those with dementia and 28.1% of those with learning disabilities.

The authors said: “Our finding of discrepancies between ethnic groups is concerning. It requires action, and further investigation.

“Possible drivers include systematic barriers to healthcare access, and vaccine hesitancy amongst certain groups; it may also only arise in the very earliest stages of this new vaccination programme.

“The reasons underpinning variation in Covid-19 vaccination coverage are not yet understood, and information presented here should not be misinterpreted as a criticism of the rapidly established NHS vaccination campaign.

“Further research is needed to understand and address the observed lower coverage among people from more deprived areas, and the striking disparity between ethnic groups.”

Campaigners argue many in Black, Asian and minority ethnic (BAME) communities are “nervous” because of a litany of questionable historical and modern day medical treatments, and repeated examples of healthcare benefiting white people disproportionately – with non-white people generally experiencing poorer health outcomes throughout their lives.

Vaccines minister Nadhim Zahawi has also expressed concern that vaccine take-up may be lower in ethnic minority groups and this week  a cross-party group of Black MPs made a video to “unite against the spread of vaccine misinformation” and tell people it is safe.

The government has said it aims to have offered a jab to people in the first four priority groups by February 15, and to everyone in all nine priority groups – including all over-50s, extremely clinically vulnerable people and over-16s with underlying health conditions – by spring.