This week the Department of Health highlighted the UK’s “influenza pandemic preparedness strategy”, originally published in 2011. It remains the core public document to guide the likely public response.

These are some of its key points:

1. What is a pandemic? How is it defined?

Influenza pandemic planning in the UK has been based on an assessment of the “reasonable worst case”. This is derived from the experience and a mathematical analysis of influenza pandemics and seasonal influenza in the 20th century. This suggests that, given known patterns of spread of infection, up to 50% of the population could experience symptoms of pandemic influenza during one or more pandemic waves lasting 15 weeks, although the nature and severity of the symptoms would vary from person to person. (Para 2.19)

This is the scenario for which that health and other public officials should have prepared for. Given there have only been 13 confirmed cases and no deaths in the UK, it is clear that the current coronavirus situation is nowhere near as bad at this stage.

For deaths, the analysis of previous influenza pandemics suggests that we should plan for a situation in which up to 2.5% of those with symptoms would die as a result of influenza, assuming no effective treatment was available. (Para 2.20)

This is a top-end assumption. Expert estimates, cited by the World Health Organization on Monday, indicate the death rate in Wuhan, the Chinese city at the centre of the outbreak, is between 2% and 4% – but more widely across China the figure is at 0.7%.

Influenza pandemics are intrinsically unpredictable. Plans for responding to a future pandemic should therefore be flexible and adaptable for a wide range of scenarios, not just the “reasonable worst case”.

An important qualification.

Taking account of this, and the practicality of different levels of response, when planning for excess deaths, local planners should prepare to extend capacity on a precautionary but reasonably practicable basis, and aim to cope with a population mortality rate of up to 210,000 – 315,000 additional deaths, possibly over as little as a 15-week period and perhaps half of these over three weeks at the height of the outbreak (Page 17)

This appears stark, although numbers are necessary to determine a response, particularly in the health service.

2. How many people could get ill? What impact will that have?

Up to 50 per cent of the workforce may require time off at some stage over the entire period of the pandemic. In a widespread and severe pandemic, affecting 35-50 per cent of the population, this could be even higher as some with caring responsibilities will need additional time off. Staff absence should follow the pandemic profile. In a widespread and severe pandemic, affecting 50 per cent of the population, between 15 per cent and 20 per cent of staff may be absent on any given day. These levels would be expected to remain similar for one to three weeks and then decline.

The assessment tells planners they have to expect widespread sickness absence from work. Elsewhere it assumes the average sick leave could be a week and half. If half the population was affected, the impact on the economy could be £28bn, although such figures are highly speculative.

3. What would the impact be on schools - could they be closed?

There is modelling data highlighting the potential benefit of school closures in certain circumstances, both in terms of protecting individual children from infection and in reducing overall transmission of the virus in the population. However, to be effective prolonged closures are required. This would involve schools over a wide area, but carries a risk that social mixing of children outside school would defeat the object of the closures. (Para 4.23)

This one of the clearest elements of the document, as it describes how closing schools could help not only youngsters but also prevent wider transmission.

Using a precautionary approach in the early stages of an influenza pandemic and depending on the public health risk assessment, directors of public health may advise localised closures (individual schools or catchment areas). (Para 4.24)

This spells out that if closures were deemed advisable – and currently they are not - this would only happen in a “high impact” situation, and should not be the focus of school planning.

Once the virus is more established in the country, the general policy would be that schools should not close – unless there are specific local business continuity reasons (staff shortages or particularly vulnerable children). This policy will be reviewed in light of information about how the pandemic is unfolding at the time. (Para 4.24)

This seems surprising, that schools should stay open if the pandemic virus were to become more established, although it wisely says that would be subject to review.

4. What about national and international travel? Will there be lockdowns?

There are no plans to attempt to close borders in the event of an influenza pandemic. The UK generally has a high level of international connectivity, and so is likely to be one of the earlier countries to receive infectious individuals. Modelling suggests that imposing a 90% restriction on all air travel to the UK at the point a pandemic emerges would only delay the peak of a pandemic wave by one to two weeks.

Closing borders is pointless, the document argues, making clear there are limits to extreme measures. Already Matt Hancock, the health secretary, has noted that Italy was one of the few countries to try temperature screening at airports only for the country to have the largest number of cases in Europe.

There is also a lack of scientific evidence on the impact of internal travel restrictions on transmission and attempts to impose such restrictions would have wide-reaching implications for business and welfare.

The assumption is that Italian-style lockdowns will not be applied in the UK. Government planners are keen to minimise the economic impacts, although the reality is that in a serious situation people will be reluctant to travel, and many essential services will be affected by sick leave.

5. What about law and order in a crisis?

In a severe pandemic, factors such as pressures on the health services, potential prioritisation of clinical countermeasures, measures to control the spread of infection, possible shortages of basic necessities or short-lived disruption to essential services could result in disturbances or threaten breakdowns in public order. (para 7.15)

This may be the most alarmist passage in the document, although immediately after the manual emphasises the importance of “preserving the rule of law, maintaining the democratic process and ensuring public safety”.

The military may be called upon to provide assistance, although planners are also warned that “pandemic resilience plans should not therefore assume that local military units would provide support or have personnel available”.

You can read the full document here:

