Nearly 65 per cent of the UK’s strictly-Orthodox community may have been infected by Covid-19, a new study by the London School of Hygiene and Tropical Medicine (LSHTM) has shown.

Amongst adults and children in secondary school within the Charedi community, this figures rises to a staggering 75 per cent, according to the new published research.

The study, conducted with the University College London’s Great Ormond Street Institute of Child Health and the Medical Advocacy and Referral Service (MARS), a healthcare organisation based in the Strictly-Orthodox Jewish communities, also showed that 28 per cent children under the age of five had been infected, rising rapidly to more than 50 per cent among primary school-aged children.

Last year, during the first wave of the pandemic, members of a tightly-knit strictly-Orthodox Jewish community in the UK approached LSHTM researchers to help them understand the extent of infection in their community.

The JC understands that a sizeable donation towards the cost of the research was provided by the community itself.

The study, which was published on Tuesday, said the “estimates are amongst the highest sero-prevalence of SARS-CoV-2 described anywhere in the world to date.”

But while infection rates among the strictly-Orthodox community may have peaked after the Purim festival last March,  before the UK government introduced the first lockdown later that month, the subsequent fall in infections suggests that many in the community obeyed the rules after they were introduced later that same  month.

The data, which is yet to be peer reviewed,  suggests suspected infections in the UK Charedi community peaked in early March and fell sharply during the first lockdown after it was announced on March 16.

Cases then began to rise again throughout the autumn of 2020.

Noting the drop in the infection levels after lockdown was introduced, the  report states: “Rapid declines in self-reported illness followed the introduction and adherence to lockdown in March, demonstrating that even in this highly connected community, such measures are effective at reducing transmission.”

The overall 65 per cent Covid-19 infection rate among the Charedi community compares to recent estimates by the Office for National Statistics of 6.9 per cent nationally and 10.8 per cent  in London.

The infection rate among children aged 2-15  in the strictly-Orthodox community is shown to be four times higher than the reported national average.

Overall, men were found to have a higher rate of infection than women.

Dr Michael Marks from LSHTM who co-led the study said: “Our work has revealed the extremely high rates of infection in this very interconnected population. Working in tandem with the community we are conducting further work to understand the potential factors involved. These findings could support potential new interventions that may help reduce infection in the community.”

The LSHTM’s Dr Rosalind Eggo, co-lead on the study, said of results: “It is one thing to hear there are differentials, and say that one group is at higher risk.

“But when you get a number like this – three quarters of this population have been infected  - it really emphasises the risks between communities that the UK is facing is really variable.”

Assessing the peak level of Covid-19 within the community after Purim on March 9 last year, Dr Marks told the JC: “We know Purim, one of the main Jewish religious festivals, which occurred before there were any restrictions, and at time when the UK government did not think there were that many cases of Covid 19  circulating in the general community - those two things interacted.

“If you recall back to March last year, firstly it was suggested there were a few cases, then a lot of cases.  And then we went into lockdown.

“We were wrong basically about how many cases there were.

“This is speculation, but it was seems as though there was more widespread infection in all communities in early March.

“There was a major religious festival, and so people had a lot of interaction at that time.

“So that suggests, people were still acting normally, because they had been told they could do so when there were more cases circulating than we were aware of.”

The researchers say other reasons behind this high rate of infection in the community are not yet clear. But strictly-Orthodox families have significantly larger households than the UK average (the community averages 5-6 individuals per house compared to a UK average of 2.3).

They also live in areas of increased population density, and in pre-pandemic times regularly attended communal events and gatherings.

In order to obtain the data, the researchers triangulated when people reported their illness with their antibody status.

It began in earnest in September, when the LSHTM team c was awarded £249,000 from the National Institute for Health Research (NIHR) and UK Research and Innovation (UKRI).

“It’s not straightforward to work out when somebody was infected on an antibody level,” admitted Dr Marks.  “What is recorded on this paper is the total proportion of people who have been infected at some point, during the ten month time span. We know when people think they were unwell. “

Working closely with the community, the research team invited more than 1,750 individuals to complete a demographic and medical information survey and provide a blood sample between November and early December 2020. This was then tested for SARS-CoV-2 antibodies.

Blood samples from 1,242 individuals were collected.

The authors acknowledge some  limitations of the study, including that approximately 40 per cent of households that were approached agreed to take part in the study.

But this is similar to other national COVID-19 household surveillance studies, such as the ONS COVD-19 Infection survey.

They also note that self-report of presumed COVID-19 illness may be unreliable. However, timings of self-reported illness match well to national surveillance. Self-reported illness was also strongly associated with the presence of antibodies suggesting this was a broadly reliable metric.

Dr Marks added: “The rates we observed are among the highest reported anywhere in the world to date.

“As our survey was completed by early December 2020, prior to the subsequent surge in cases, it is likely that the overall burden of infection in this community is now even higher.

“Whilst lockdown measures were still very effective at reducing transmission, over the course of 2020 three out of four secondary school aged children and adults were still infected.”

Both Dr Marks and Dr Eggo praised the role the strictly-Orthodox community itself played in making the study happen.

An approach from communal leaders, who wished to gain further insight into why their community was being so hard hit by the virus, led to the study.

Funding for the research was also made available from the strictly-Orthodox community itself.  “This study happened because the community approached us,” said Dr Eggo.

“They put their hands up and said we want to try and understand the epidemic. This work is not going to just benefit that community -  will also benefit everybody.”

Rabbi Hershel Grunfeld, Founding Director of MARS said, “The decision to initiate this study was made in May 2020, during the first wave of the Covid-19 pandemic, with senior Rabbinical support. By developing a better understanding of the effect of Covid-19 in strictly-Orthodox settings, the study’s purpose is to protect people, save lives and inform safety planning within communities.

“We want to thank the LSHTM team for their support in developing this research project with these objectives in mind."

The team say that the characteristics of the community involved are shared with many other ethnic and religious minority groups. The findings are therefore likely relevant to understanding the severe impact COVID-19 has had on these groups in the UK.

“The Strictly-Orthodox , we know along with other ethnic minority groups, have much higher infection rates than white caucasians,” said Dr Marks.

“It wasn’t at all surprising that an ethic minority group had a higher rate of injection. But was as I surprised that it was quite as high it was – ‘yes.’

“But I don’t have anything to benchmark that against.  But having seen this data, I wouldn’t be that surprised if I went and studied a tight-knit South Asian community in parts of the Midlands, and we found similar data.”

He said it was a “privilege” to have been able to work on the study it was a “community partnership approach” that “could be a blueprint to further understanding of the impact of Covid-19 on other groups in the UK.”

LSHTM has a strong international presence with over 3,000 staff and 4,000 students working in the UK and countries around the world, and an annual research income of £180 million.