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?
Children who have COVID-19 are not likely to develop severe symptoms. They are also much less likely to die from the disease than people in older age groups. there is some evidence on infection risk for under 13s and for BAME children but more data from well-designed studies is needed to draw conclusions.
DOI: https://doi.org/10.58248/RR38
This article summarises key findings about how COVID-19 affects children, and the role that children have in the transmission of the virus in the population, their local communities and in schools. This is a complex interplay between how susceptible children are, how infectious they are, the proportion of children in a population, and how they mix with other age groups. This is relevant to implementing policies that seek to limit transmission by children. The national governments’ plans for wider openings of education settings are also discussed, with an overview of the key public health measures and plans to contain outbreaks associated with schools. New research studies that will inform ongoing policy decisions are also highlighted.
A detailed summary of the scientific evidence describing children’s susceptibility to COVID-19, the clinical outcomes for children, children at risk, and children’s role in transmission of the virus in the population is discussed in POST’s article on COVID-19 in children. The key points are:
Some children who are deemed to be clinically extremely vulnerable have been advised to shield. Shielding for children means that they must stay at home and not attend school or college before 31 July. From 1 August the government advice in England, Northern Ireland and Scotland is that shielding may pause, subject to local levels of community transmission. In Wales the advice is that shielding should continue until 16 August. If shielding remains paused this means that this group of children can return to schools when they open.
There are some limited data suggesting that children from black and minority ethnic groups are at increased risk of having severe COVID-19 disease. This is consistent with the evidence of increased risk for adults from black, Asian and minority ethnic backgrounds summarised in a report by Public Health England. These studies involve very small numbers of children. Much larger samples are needed in order to draw firm conclusions about any increased risk, what the magnitude of the risk might be and how it might differ between ethnic groups and in comparison with adults.
Understanding the role that children play in transmitting the virus is of significant policy relevance, since measures can be taken to limit the opportunities for transmission to take place between children and adults – notably closing childcare and educational settings. Research can also inform whether and how measures can be reversed, modified or re-imposed. Information about transmission is also critical in designing population immunisation programmes; although a COVID-19 vaccine is not expected for at least 12 months at the earliest if a successful vaccine candidate(s) is found. For example, children in the UK are immunised against seasonal influenza, which in addition to protecting the children themselves, also confers protection to the wider population because children readily transmit influenza virus in the community.
The extent to which children transmit the virus is not yet fully understood and is complicated by the fact that there are asymptomatic cases. However, there does not appear to be good evidence to support the suggestion that asymptomatic children play a key role in spreading the virus. Data from research in community clusters and larger studies that test population samples, such as those carried out South Korea and Iceland, report fewer cases in children than adults, suggesting that children may be less likely to get the disease.
Understanding transmission within a family (or any larger group or community group) requires a detailed epidemiological study to identify who has had the infection, and whether they had symptoms or not. These studies also identify the first person infected in a family cluster, and contact tracing identifies where and from whom they contracted the infection. Studies of early clusters of disease in families and small groups showed that children were not the source of infection in those groups. For example, in a study of a disease cluster in the French Alps, a 9-year-old child with symptoms had made a large number of contacts during a trip to the Alps and then at three different schools. Of the 169 tested contacts, only one person tested positive for the infection.
Asymptomatic and pre-symptomatic transmission of the virus have been reported and there is also some evidence that those who have symptoms are more likely to transmit the virus than those who are asymptomatic. A study in the Netherlands reported that children have a minor role in transmission and that the virus is primarily spread between people of similar age. They also found that it is less common for adults to infect children, but when this does happen it tends to be within a household.
The Scientific Advisory Group for Emergencies (SAGE) is advising the UK Government on COVID-19. In its discussions it has considered the possible risk to older people from contact with their grandchildren, notably in the context of school closures. This is relevant because the risks from COVID-19 increase with age. As part of its analysis, SAGE reviewed demographic data on parents and grandparents in the population. Parents with primary age children are usually younger than the general population (less than 50 years old). Within this group, adults with pre-existing health conditions (comorbidities) are at increased risk from COVID-19 than those with no health conditions. A substantial proportion of people in high-risk age groups have one or more primary age grandchildren. There are no data in the SAGE papers on transmission between young children and their grandparents.
The data so far indicate that schools are a low-risk setting for transmission and that there is no significant transmission among children or from pupils to teachers. A systematic review of multiple studies to determine the settings linked to viral transmission reports that there have been few disease clusters in school settings. A report prepared for SAGE on superspreading events also noted that few clusters of disease have been linked to school. There is some evidence suggesting that younger children (aged under 10 years) transmit the virus less than older children. This has significance for how public health measures may need to vary between primary and high school settings.
An Australian study looked at all COVID-19 cases reported in primary and high schools in New South Wales between March and mid-April and reported preliminary findings with data up to 21 April. 18 individuals (nine pupils and nine staff) were identified as COVID-19 cases in 15 schools (10 high schools and five primaries). Close contacts of these cases included 735 pupils and 128 staff. There were no cases in any staff members as a result of contact with the infected school pupils. Two children were identified as having had COVID-19 and it is highly likely, but not certain, that they contracted the virus from the infected school contacts. A limitation of this study is that not all participants were tested for the virus.
Details from a study (not peer-reviewed) in the Netherlands reported to the Dutch Parliament was published by SAGE in April. The key findings were that there were no clusters of infection linked to schools or childcare settings and that children were the least likely to infect other people.
Another study analysed transmission in schools in Ireland before school closures on 12 March. Six notified cases reported to the Public Health Department were the basis for an epidemiological contact tracing study of 1,155 people. The cases:
Analysis showed that no infection was acquired in a school setting. Four cases were related to travel, one was linked to a close contact in a recreational setting outside school and the other in a work environment outside school. There was no onward transmission to children or adults in the schools and other settings. The children and adults mixed during high-risk transmission activities including music lessons and choir practice.
Scientists at the Pasteur Institute have analysed transmission in one high school and primary schools in France. A pre-print paper of the study in the high school was published in April. A pre-print study of the study in primary schools was published in June. Key findings:
A review of all the relevant research on overall community transmission by children was published as a pre-print (this means that it has not yet been reviewed by other scientists) by a group of scientists led by University College London. From analysing research studies that undertook contact tracing, the authors conclude, based on the evidence so far, that children are 56% less likely to become infected than adults. This is in line with an earlier modelling study, which concluded that under 20-year-olds were approximately 50% less susceptible to infection than older age groups. Upon analysis of wider population-level studies, the authors conclude that while it is possible that children may play a limited role in transmission, the evidence for this to date is weak. The reviewers highlight that many studies seeking to answer this question have limitations in terms of study design or quality, which make it difficult to draw conclusions with certainty.
The research so far is indicative that children may not play a significant role in spreading COVID-19, in contrast with other respiratory viruses such as influenza. More evidence from high quality large scale serosurveillance studies (that look at SARS-CoV-2 antibodies in a population) are needed to quantify the risk of transmission of the virus from children and how this differs from adults. Many such studies are underway.
Public Health England is running a surveillance programme to monitor transmission of the virus in schools – the sKIDs COVID-19 programme. This involves testing pupils and staff in 100 schools across England from May until the autumn. A combination of tests are used to detect current infection (swab testing) and previous infection status (antibody testing). Information about participants’ health and illness over the course of the study is also being recorded.
As school closures have not been used in isolation in any country it is not possible to determine with certainty the impact this measure alone has had on transmission of the virus. Well-designed large epidemiological studies on how school openings may impact transmission are the only way in which any effect can be characterised, but even these studies have limitations.
Several outbreaks linked to schools have been reported in the international media. Without proper epidemiological analysis involving contact tracing and testing, it is not possible to attribute such outbreaks and transmission to the schools involved. It is likely that these cases are extensions of outbreaks occurring in the communities in which schools are located. International governments’ approaches to managing these outbreaks vary. Some order immediate closure of individual schools or multiple schools in a region, sometimes based on a case number threshold. Some countries have not seen increases in cases after the reopening of primary and secondary schools, for example in Denmark and the Netherlands.
Public Health England has published weekly national surveillance reports since 23 April that detail acute respiratory outbreaks (defined as 2 or more cases of influenza, COVID-19 or other respiratory illnesses) linked to particular settings. When an outbreak is suspected, SARS-CoV-2 testing takes place, and cases are connected to a setting if at least one confirmed case is linked to it. Confirmed outbreaks with at least one case linked to a school:
Outbreaks linked to schools have increased since primary and secondary schools re-opened to more pupils on 1 June. However, since testing access was expanded in April, more incidents of mild disease in young people have been detected. It is not possible to conclude with certainty from this data that transmission took place in schools. Care homes are the setting in which most outbreaks have occurred throughout this period.
At the time that schools were closed across the UK, it was unclear from the scientific data available whether it would be an effective intervention in limiting the transmission of the virus. A research article in The Lancet examined the effect of this policy and social distancing practices in schools on outbreaks of other diseases caused by coronaviruses (SARS and MERS). It reported that data on the effectiveness of school closures are very limited. Research from China, Hong Kong and Singapore found that school closures did not contribute to controlling the transmission of SARS-CoV-1. Data from UK modelling indicated that school closures might reduce deaths by an estimated 2–4%. However, modelling is highly sensitive to the assumptions used. In the early stages of the outbreak in the UK some modelling used to advise the UK Government was based on an assumption that children have the same principal role in the transmission of SARS-CoV-2 as they do for influenza virus. Research since has shown that this is not the case.
To summarise the scientific advice to date: children are about half as susceptible to infection than adults, they account for fewer than 2% of COVID-19 cases, most cases in children are mild or asymptomatic, and transmission in schools appears to be very low. Infections in children are likely to have been contracted from an adult rather than from another child. This points to school re-opening presenting a minimal risk in term of the overall transmission of COVID-19, a risk which is outweighed by the negative impact that not being in school has on children’s health and well-being:
As education is devolved, each national government has set out separate guidance on re-opening schools. These derive from high level policies on relaxing restrictions on everyday life. Decisions about lifting restrictions are determined by criteria specified by each government. These are also set in the context of the COVID Alert levels determined by the Joint Biosecurity Centre and by scientific advice from SAGE, the Technical Advisory Group in Wales and the Scottish Government COVID-19 Advisory Group, and through the four Chief Medical Officers.
There are high-level policy frameworks for education and childcare settings, and more detailed operational documents for local public health teams and school leaders that set out the necessary steps to protect staff, pupils and families, to minimise the risks of transmission occurring in schools, and on containment measures in the event of outbreaks.
Five criteria that must be met for easing measures were published on 16 April: NHS’s ability to cope; sustained and constant fall in daily death rates; rates of infection decreasing to manageable levels; operational challenges (PPE and testing capacity) can meet demand; and confidence that measures will not risk a second peak. Guidance was published for expanded school opening for all age groups from September on 2 July following an announcement by the Education Secretary on 19 June. All schools will open to all pupils in September.
Published a Coronavirus Decision-Making Summary outlining a five-step plan for each sector and the New School Day guidance for re-opening schools in August/September on 12 May, updated on 19 June, with answers to FAQs published on 24 June. Social distancing will be reduced to 1 m between pupils, but will remain at 2 m for adults. For primary schools that cannot maintain this distancing measure, a blended learning approach may be adopted, so that children have a minimum of 40% teaching time in school. Secondary schools are expected to prioritise social distancing over bubbles. This may mean that children learn at home, but they should have a minimum of 50% of their learning in school. The Northern Ireland Executive has said that other attendance patterns will be considered if social distancing guidance relaxes further over the summer.
Published a roadmap for lifting restrictions, comprising four phases – school openings are part of Phase 3, which began on 10 July. The Scottish Government also published a strategic framework for re-opening schools on 21 May and guidance on re-opening schools in August on 28 May. Public Health Scotland published a report on school re-opening on 23 June outlining three conditions that must be met before schools can reopen (adequate test and trace capacity, implementation of all necessary mitigation measures, and transparent evidence about transmission of disease). Schools will reopen on 11 August. The Government has announced that a full-time return to school is planned, conditional on scientific advice and prevalence of infections. On 16 July, the Scottish Education Secretary announced that physical distancing between children will not be required in primary and secondary schools. A final decision on the 11 August reopening date will be announced no later than 30 July.
The Welsh Government uses a traffic light approach outlining the current status of measures and changes to these determine whether measures are lifted. It published a decision framework for education on 15 May, detailed operational public health guidance on 10 June and advice from the Welsh Technical Advisory Group on 9 July. The Education Minister has stated that schools will be open to all pupils in September, subject to a continuing decline in COVID-19 infections in the community and appropriate protective measures.
While the broad principles on public health measures apply to all settings, governments are also developing additional guidance for specialised educational settings and for those pupils who have additional needs.
As with the overall public health approach, a system of controls approach is used. This creates a hierarchy of protective measures, that in total offer the greatest protection against viral transmission. Many of these are common to all the devolved nations’ approaches. These are focused on preventing the spread of infection within a school and by breaking transmission chains by limiting the interaction between groups of children and adults.
The virus is transmitted through direct or indirect contact with respiratory droplets and aerosols. The way that droplets move, settle and persist on surfaces in the environment is a dynamic process that depends on numerous and interacting factors, including air flow, light, temperature, and the layout of fixtures and fittings. The evidence to date is that most transmission is likely to take place indoors. Measures to reduce transmission in schools are similar to those recommended for a range of indoor settings. Schools are expected to undertake detailed risk assessments to develop control measure that best suit their circumstances. The main approaches to minimise risks of infection and transmission are
Public health agencies’ disease surveillance systems collect and report data at national, regional and at various local authority levels. This means that the changing patterns of disease within communities are monitored. There are a range of social distancing interventions that are less disruptive than full school closures and which may have a more direct impact on limiting transmission, and these can be implemented at the appropriate community, local or regional level.
The most important intervention is school and family engagement with test, trace and isolate programmes; the main sources of support are local health protection teams. These teams will advise on actions to take, such as which groups should not attend school and who should be tested.
Guidance for each devolved nation includes details of the action to take if someone attending a school tests positive for the infection. Local health protection teams will compile details of contacts and determine their risk of exposure. This will rely on good record-keeping by schools. Those deemed to be close contacts will be asked to self-isolate and be offered a test. If a test is negative, the 14-day isolation period applies because the virus may develop in subsequent days. In the case of a positive test, the individual must isolate for 7 days from when symptoms began, and their household must isolate for at least 14 days from when the symptomatic person first had symptoms.
In England, if two or more cases occur within 14 days or if sickness absence linked to COVID-19 is suspected, local public health teams will advise on actions to take. They may recommend that groups of pupils self-isolate – this might be a bubble or a whole year group. Testing will be focused on specific groups or the whole school as required. The control measures outlined earlier mean that closing a whole school will not generally be necessary.
In response to a rise in disease prevalence in Leicester, the Health and Social Care Secretary announced on 29 June that public health measures could not be lifted in Leicester and surrounding areas as planned on 4 July. Part of the response to the increased transmission in the area was that schools would be closed to all pupils except children of key-workers. This decision was on the basis that the number of cases in the community was increasing in those aged 0–18 years and those aged 18–65 years, but not in those aged over 65 years. An analysis by Public Health England highlighted that it is not possible to correlate the rise in cases to more children attending schools since early June, but that this association need investigating. The Department for Education published local guidance for educational and childcare settings in Leicester. The measures outlined reflect those in place during national school closures.
Seasonal influenza is a recurring risk, causing unpredictable winter pressures on the NHS. This may coincide with ongoing, and possibly increased, transmission of COVID-19. The annual influenza immunisation programme is delivered to protect those most at risk from influenza and is the most important public health intervention to reduce NHS winter pressure. In 2012, the Joint Committee on Vaccination and Immunisation (JCVI) recommended that the programme be extended to include children aged between 2 and 17 years. This is to protect children from influenza, but the other key objective of the childhood programme is also to offer indirect protection to vulnerable people by preventing transmission in the wider population. This is because children are the main spreaders of influenza virus. The groups eligible for influenza immunisation this winter are:
Those most at risk from influenza are also most at risk from COVID-19. Therefore, it is essential that the coverage of the influenza programme is as high as possible. This will be challenging in the context of possible school closures and staff absence (in both health and education settings). NHS England has written to those responsible for delivering childhood immunisations setting out the need for timely ordering of adequate vaccine supplies and that all local immunisation teams should have delivered the school programme by 15 December 2020. The target for Local Authorities in England is that 65% of eligible children are immunised; of 152 LAs in England, 59 achieved this in 2019/20.
Immunisation coverage in primary school aged children for winter 2019/20:
The JCVI has produced preliminary guidance outlining the priority groups for any future COVID-19 vaccine in a statement published on 18 June. Priority groups are frontline health and social care workers and those at increased risk of serious disease and death from COVID-19. There is very good evidence that children are much less likely to develop severe disease or to die, so it is unlikely that children will be prioritised for immunisation. The JCVI will review emerging evidence on risk factors and update their advice accordingly. The role of children in transmission of disease is also important, but the evidence to date suggests that children do not have a principal role.
The following six bodies commonly provide advice on COVID-19.
Below is a timeline of the scientific advice that was provided since February 2020 and the policy announcements on schools that the advice resulted in.
5 February: SAGE notes that there is little data about how children are affected but that there have been no reports of illness in children. In consideration of measures to limit spread, SPI-M is tasked with reporting on the impact of school closures in different scenarios. SAGE notes wider impacts of school closures and that closures may have a limited impact on transmission.
10 February: SPI-M produces a paper discussing the impact of possible UK school closures and concludes that it would have most benefit at the peak of a UK epidemic. This discussion took place when there was very limited knowledge about the transmission of the virus in children and how severe infections are in children.
11 February: SAGE notes that the disease appears to be less severe in children.
13 February: SAGE discusses the purpose of school closures which could delay the first wave of an epidemic or the peak. To achieve this, closures would need to be long and would be unlikely to reduce the total number of cases. SAGE commissions modelling on a range of closure scenarios.
20 February: SPI-M updates its consensus view on mass school closures. Modelling data is used to develop how school closures may impact the epidemic. Such modelling is highly sensitive to the assumptions upon which it based. The view is that, while closures may delay the peak of an epidemic, they are unlikely to reduce the overall number of cases. SAGE discusses this paper and asks SPI-M for modelling of selective school closures.
25 February: SAGE discusses a modelling paper on the impact of combined measures to limit spread, including school closures. To be effective, the duration would need to be long.
27 February: SAGE reviews possible measures to mitigate spread and notes that they will delay the peak but are unlikely to reduce the overall number of infections.
3 March: SAGE discusses insights from behavioural science and how this could inform public communication about interventions to limit transmission.
5 March: SAGE discusses behavioural and social interventions and notes that school closures would have smaller effects on the epidemic curve than other measures.
10 March: SAGE notes limited data indicating that children with the infection experience mild illness. There is no data yet on their role in transmission.
16 March: SAGE discusses NHS critical care capacity and that additional social distancing measures may need to be introduced as soon as possible. SAGE remains of the view that school closures are one of the least effective single measures, but notes that they may be necessary to reduce NHS critical care demand.
17 March: SPI-B considers options for schools remaining open to key-worker children and whether the health benefits of school closures are outweighed by other factors, for example if children are cared for by grandparents. SPI-M updates its consensus view on the impact of school closures and highlights that the impact is likely to be lower than compared with an influenza epidemic. It discusses whether school closures could reduce the reproduction number and thereby prevent NHS critical care capacity being breached, and the timing and duration of closures. The London School of Hygiene and Tropical Medicine prepare a paper for SAGE on the impact of adding school closures to other social distancing measures.
18 March: University of Warwick provides a report for SAGE outlining the impacts of school closures. The MRC Centre for Global Infectious Disease Analysis at Imperial College London produces a report for SAGE on the timing of the introduction of school closures.
SAGE considers these reports – modelling data support national school closures, but SAGE notes the uncertainty of the impact on R. It discusses the risk to grandparents and older people if childcare is displaced to them, and the impact of keeping schools open for key-workers’ children. SAGE notes the importance of clear public messaging. It recommends national school closures as soon as possible in order to prevent NHS critical care capacity being exceeded.
The Prime Minister, the First Minister for Northern Ireland, the Minister for Education in Wales, and the First Minister in Scotland announce that schools will close at the end of the school day on 20 March.
1 April: SPI-B reports on behavioural aspects of lifting social and behavioural interventions.
2 April: SAGE discusses options for lifting interventions and how these might be sequenced.
7 April: The UNCOVER network produces a paper for SAGE outlining current understanding of transmission of the virus by children. SAGE notes that the role of children in transmission is unclear. It also discusses the social, developmental and psychological impacts of school closures.
16 April: SAGE discusses transmission in children. Evidence is limited but children have milder disease. Their susceptibility to transmission from adults is unclear. Whole household testing is the best way to understand the infectivity of children. SAGE advises that lifting school closures should be based on integrated science and policy thinking and should recognise that children are not a homogenous group. SAGE advises that priority research questions on transmission in children and schools be directed to research funding councils.
28 April: SAGE discusses a rare syndrome in children with a probable link to COVID-19.
29 April: A paper is compiled for SAGE on susceptibility and transmission in children.
30 April: A joint paper by SPI-B and SPI-M outlines the possible behavioural responses to scenarios for relaxing school closures.
SAGE advises on the need for more comprehensive availability and deployment of the seasonal influenza vaccination for winter 2020 and that consideration be given to vaccinating the whole population. It also discusses the principles for an effective contact tracing system.
SAGE notes that evidence on transmission by children and their susceptibility to infection is inconclusive, including whether younger children are less susceptible. It also considers modelling data relating to schools.
1 May: SAGE holds a meeting focused on children and schools. Papers on transmission of COVID-19 in the Netherlands, key findings from several studies and a modelling paper by the Task and Finish Group on the role of children in transmission are considered. SAGE discusses the risks of the disease to children of different ages. Re-opening options related to younger children are lower risk than those related to older children. The indirect effects of re-opening schools are likely to have a greater impact on transmission than schools themselves. SAGE advises that effective measures are needed to monitor changes in schools and to respond to cases in schools before schools re-open. Response plans to cases in schools could be class or whole school closures.
In a separate meeting, SAGE outlines the key features for an effective test and trace system. At least 80% of contacts of an infected person would need to be contacted for a system to be effective and as quickly as possible, ideally within 48 hours.
5 May: SAGE advises that lifting of social and behavioural measures, such as school re-openings, be based on incidence of disease and not on set pre-determined dates. SAGE discusses data from modelling scenarios for lifting measures. The impact on transmission is contingent on an effective test and trace system. The concept of social bubbles is discussed; SPI-M and SPI-B are asked to consider this and report their view.
14 May: SAGE advises that further releases of distancing measures should not be contemplated until effective test, trace and isolate systems are operational.
18 May: The ONS provides SAGE with demographic data on parents and grandparents of primary school aged children.
20 May: SAGE’s Children’s Task and Finish Group prepare a paper for SAGE on the sequencing of social distancing measures in schools. The importance of test and trace systems are emphasised, with 80% coverage and rapid results required. The paper highlights the risks from introducing too many changes simultaneously and the importance of secondary impacts of extended school closures.
21 May: The Government Office for Science provides a paper for SAGE on the risk of COVID-19 amongst parents and grandparents of primary school aged children. SAGE discusses the sequencing of lifting social distancing measures and notes how the impacts of lifting multiple, separate changes accumulate. It considers modelling on the impact of school re-opening under different test and trace scenarios and notes there is little headroom without test and trace in place if schools re-open. Opening both primary and secondary schools has the potential to recreate significant transmission networks. Teachers and parents are low risk as they have a relatively young age profile (though some people in those groups may be at higher risk for other reasons). It advises that opening schools requires significant efforts to minimise transmission (using mitigation measures in schools) and careful monitoring of infections.
24 May: The Prime Minister announces that schools will open to more children from 1 June.
28 May: SAGE notes that lifting social and behavioural interventions should be linked to the COVID-19 alert level. It also noted verbal reports of outbreaks in schools (including residential settings and schools for children with special educational needs) and advises that these should be investigated.
1 June: Primary schools in England open to children in nursery, reception and Years 1 and 6.
15 June: Secondary schools to open for face-to-face contact with children in Years 10 and 12, and 16–19 year olds due to take exams in 2021.
19 June: COVID-19 Alert level moves to from 4 to 3.
19 June: The Education Secretary announces that schools in England can reopen to more pupils if they are able to do so.
2 July: The Education Secretary announces that schools in England are expected to open to all pupils in September.
9 July: Technical Advisory Cell Children and Education Subgroup publishes advice on return to school.
16 July: The Scottish Government COVID-19 Advisory Sub-Group on Education and Children’s Issues publishes new advice on physical distancing. This is not required between children in primary and secondary schools, and is subject to local transmission of the virus.
11 August: Schools expected to reopen in Scotland.
24 August: Schools in Northern Ireland expected to reopen to priority pupils.
1 September: Schools in Wales expected to reopen to all pupils.
2 September: Schools in England expected to open to all pupils (exact dates vary according to region).
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