Coronavirus (COVID 19): Advisory Subgroup on Public Health Threat Assessment: preparing for a winter emergency report

The incidence of Covid-19 infections was low during the summer and NHS Scotland had capacity to deal with the backlog of patients needing screening, assessment and treatment. However, winter is approaching, and it always brings added pressure on the NHS. In addition to seasonal outbreaks of influenza, there is always an increase in admissions to hospital with circulatory problems such as heart attacks or stroke and worsening of respiratory problems such as asthma and bronchitis. Some of the threats facing us are:

1. Will a resurgence of Covid-19 produce a second wave of infection and deaths, perhaps as serious as the first wave?

2. Will the appearance of winter flu, which normally produces an increase in hospitalisations, be worse than usual if it occurs alongside Covid-19?

3. Will coincidental outbreaks of Covid-19 and influenza overwhelm the ability of NHS Scotland to provide effective health care?

The Public Health Threat Assessment Group has considered these risks and this paper suggests action which might be taken to minimise risk.

Will there be a second Covid-19 wave in winter?

Scotland has done well to suppress the first wave of infection and, for a time, public health staff were successful in investigating and controlling dealing local clusters. However, the usual pattern for respiratory pathogens suggested that a more serious outbreak would appear as we entered winter. This is the situation we face in late September.

Although Covid-19 is a different virus from influenza, some insight into its possible behaviour in winter might be gained by considering the pattern of influenza outbreaks. It appears that influenza pandemics tend to follow a pattern; a spring wave, followed by a severe winter wave and another spring wave. After the First World War, Spanish flu came in three waves, with the second being more deadly than the first. Of the last 10 significant respiratory disease outbreaks, five have had significant subsequent waves. Although Covid-19 is not an influenza virus, it is like influenza in that it is spread by droplets and a winter wave in the northern hemisphere could be similar to, or worse than the spring and summer wave we have already seen.

Australia was seen as a success story for suppression. However, it seems to have experienced a true winter wave. Melbourne had to go back into lockdown after a significant increase in the number of new cases. A second wave in Europe is also being experienced as the number of cases increases significantly in some countries. Data suggests that increased transmission is probably due to increased social contact following relaxation of control measures. The increase in cases in West Central Scotland prompted a reimposition of controls on social contact in July and we are now seeing indications that reducing opportunities for socialising inside people's homes is beginning to have an effect in reducing transmission. The Test and Protect process has confirmed, following discussion with contacts of positive cases, that hospitality and home visits seem closely associated with transmission of the virus. This pattern is to be expected and further measures to control social contact are now being implemented. Australian research shows that the virus is more easily transmitted in conditions of low humidity. Low temperatures and low levels of ultraviolet light are also said to enhance survival of the virus. This suggests that there may be an increase in the infectivity of Covid-19 as winter approaches. If it did, indeed, become more infectious in winter, it might require a return to more stringent controls on social contact.

A paper outlining  possible scenarios for a resurgence of Covid-19 has been produced for the Scottish government by the Chief Statistician.  The paper makes it clear that the scenarios describe what could happen, not what will happen.  The implications of these scenarios for hospital admissions are considerable. They make it clear that, without continued vigilance, the pressure on the NHS might be as great, or, indeed, greater than we saw in early summer. The combination of an increase in Covid-19 admissions together with the increase in demand for hospital care arising from a winter flu epidemic might, without significant mitigation efforts, overwhelm the health and care services.

What are the implications of a winter flu epidemic?

It is difficult to predict just how severe a flu epidemic could be. One possibility is that it might be mild this year. Since it is spread by exhaled droplets, an effective way to prevent flu spreading is to encourage social distancing, mask wearing and frequent hand washing. Continued messaging on the importance of these habits in preventing spread of Covid-19 may have the added benefit of limiting spread of flu, reducing demands on the NHS.

Inevitably, however, there will be some patients with flu. Since they usually present with temperature, muscle pains and respiratory symptoms, they may be difficult to distinguish from patients with Covid-19 infections. At present, patients with these symptoms are directed to Covid-19 assessment centres (CACs) where their symptoms can be assessed. In many cases, they can be sent home to self-isolate. If their symptoms are severe, they are referred to hospital. This strategy of diverting possible cases of Covid-19 away from GP surgeries has been important in maintaining effective primary care services. The lower incidence of possible cases has meant that some of these CACs have been stood down. Since it appears likely that the number of people presenting with symptoms of flu or Covid-19 will be increasing in coming months, Health Boards are considering the establishment of virtual hubs allowing patients to be assessed with less risk to staff.

At present, patients with symptoms of temperature, cough or loss of taste or smell can be asked to self-isolate for 14 days. If the patient is breathless on exertion, tissue oxygen saturation can be measured. If this suggests the need for oxygen therapy, the patient is referred to hospital. Ideally, patients with symptoms would be tested for Covid-19 and/or flu at the time of presentation at the CAC and a number of Health Boards have indicated their interest in testing patients presenting with respiratory symptoms against a wide range of pathogens such as influenza, RSV etc. Adding Covid-19 to that panel of tests is not straightforward. A review of different methods of testing suggests that limited numbers of rapid tests for Covid-19 will be available over winter. However, rapid testing for flu has been available in hospitals for the past few years and these tests should help in diagnosis of  patients with high temperatures.

However, testing which provided rapid results (within an hour) at the time of presentation to Emergency Departments of people with symptoms for Covid-19 or flu might improve patient management. Such tests are possible but not yet widely available. If some Boards are able to carry out these rapid tests, it would be important to evaluate them and report on the impact they are having.

It is also recommended that efforts are made to increase capacity for testing of staff and patients in care homes with symptoms of Covid-19 or flu in anticipation of an increase in cases over the winter. Some health boards are testing care home staff weekly. An important issue for care home staff has been the number of false positive tests being reported. Staff having a positive test are retested and often, the second test has been negative.

Accurate and rapid tests for Covid-19 are at the heart of efforts to suppress outbreaks.

The Public Health system in Scotland has shown itself to be highly capable in dealing with these sporadic cases. Improved methods of contact tracing and more accurate and rapid testing capacity will help enhance Scotland's capacity to deal with another wave of cases.

Continued research and development on these fronts is required.

Prevention of a wave of influenza cases: Who gets flu vaccine and where is it administered?

Vaccination against Covid-19 is unlikely to be available before winter. However, each year, vaccination against influenza is offered to a range of vulnerable individuals. This year, efforts should be made to suppress as much as possible the impact of flu with a concerted effort to ensure a very high uptake of flu vaccine. Usually, flu vaccine is offered to those at risk because of underlying conditions, those over 65, health and care workers, and young children. It is intended this year we will expand this list. For example, the suggestion is that it should be offered to all those over 55.

The second issue is how flu vaccine will be administered. At present, GP surgeries are observing strict rules about social distancing, the use of masks and PPE and they are using video conferencing to reduce the number of patients attending their surgeries. If we are successful in getting a high uptake of the vaccine, it is likely that many surgeries will have insufficient room to immunise patients and keep them safe. Hiring local halls and running a mass vaccination campaign would be quicker and safer. Health boards should be asked to examine capacity for mass vaccination and make appropriate arrangements. 

IT and record linkage for those being tested seems, currently, to be a problem. Public Health colleagues have made the point several times during discussion about the importance of accurately recording test results and who has had flu vaccine. Contact tracing as part of the Test and Protect programme becomes considerably more complicated if records are not up to date. The process for updating records of test results and vaccination uptake needs to be examined and, if necessary, improved

Protecting the NHS

Clearly, the best way to protect the NHS is to continue to suppress community transmission.  Continued emphasis on social distancing, masks, frequent hand washing will be essential as we move into winter. Hopefully, rapid detection and control of sporadic outbreaks will continue and prevent a second wave of infections. In order to reduce pressure on primary care, streaming of patients with symptoms should continue to be towards CACs or other reception areas in Emergency Departments which are taking full precautions against Covid-19.

The group heard a presentation on winter preparedness in hospitals. Considerable work is going in to planning for a winter which is likely to pose different challenges from usual.

For example, where patients are considered to need hospital care, it will be necessary to set up zones within hospital to which suspected Covid patients can be directed. Covid-19 free zones should be designed to keep staff and patients separate from those patients with the virus. This may not be possible in every setting but Boards should be planning how patients with symptoms of infection and those with other problems such as suspected cancer or cardiovascular problems will flow through different departments.

Issues encountered in February and March such inadequate provision of PPE, testing capacity and materials for infection control are being anticipated and dealt with.

Similarly, the issues affecting Care Homes need to be reviewed. Regular testing of staff has already been mentioned.

The plans for winter preparedness that we have seen seem comprehensive. As mentioned, different Health Boards are facing different challenges. It would be important to involve them all in an improvement collaborative. The Unscheduled Care Collaborative seems like an ideal mechanism for sharing best practice and Professor Leitch has already been involved in discussion about this aspect of planning for winter.

The possibility of vaccine against Covid-19

A recent seminar given by Sir John Bell, Regis Professor of Medicine at Oxford offered a real prospect of an effective vaccine becoming available in late autumn. If, indeed, it is shown to be safe and is licensed for production, it will take some months for production to be able to cope with the numbers needed to eradicate the virus. The protocol for who gets the vaccine first will probably follow a similar arrangement to the arrangements for seasonal flu vaccination. The PHTAS has already discussed a flu vaccination protocol and submitted it to the Chief Medical Officer for consideration.

Recommendations

1. As we enter winter, continued emphasis on the importance of social distancing, mask wearing, hand washing and other mitigation actions against Covid-19 should be maintained until there are no sporadic outbreaks and clear evidence that it has been eradicated. This may require an effective vaccine.

2. There should be continued support for rapid methods of testing for Covid-19, influenza and other respiratory viruses. Health Boards across Scotland should be encouraged to implement these methods. In addition to improving care of patients, such facilities would help Public Health departments in dealing with sporadic outbreaks.

3. An expanded flu vaccination programme should take place with strong messaging on the importance of accepting an invitation to be vaccinated. Support from professional organisations will enhance uptake in health and care workers.

4. The administration of flu vaccine in expanded numbers could potentially overwhelm GP surgeries which are often unsuited to social distancing etc. Boards should consider providing vaccination sessions on a large scale in appropriate premises.

5. Accurate record keeping as to who is vaccinated against flu will be essential for accurate management of testing and contact tracing for Covid-19. Boards need to ensure records are updated regularly.

6. A winter wave of Covid-19 now seems likely. Seasonal flu, however, has been suppressed in Australia as a result of the social distancing measure enacted to prevent spread of Covid-19. GPs and hospitals see patients every winter with complications of flu. There may be less flu around this winter so patients presenting with upper respiratory tract symptoms may be more likely to have Covid-19. Boards need, now, to be preparing to keep GP surgeries and hospitals safe and open in winter. This might involve continuing support for the Clinical Assessment Centres, some of which have been closed with the decline of positive cases. Boards should now also begin to plan for separation of care of infectious patients from areas in hospital in which uninfected cases are investigated and treated.

7. We should plan for regular testing of staff and patients in care homes should a second wave emerge.

8. Stockpiling of PPE and sanitising preparations should continue. Even if there is no increase in Covid-19 risk, control of seasonal flu is enhanced by the same protection methods.

9. Preparations for administration of Covid-19 vaccination over this winter may need to be made at some point. It is likely that arrangements will be very similar to those for flu vaccine

Managing the programme

These recommendations require a wide range of actions by the whole health and care system. An effective response to winter will be complex as different organisations have to deal with different challenges. NHS Scotland has had considerable success in the use of improvement science in the patient safety programme, the early years collaborative and other programmes. Discussion with Professor Jason Leitch has taken place and we believe that using a collaborative approach across Scotland would speed up the implementation of effective approaches to managing winter pressures. Involvement of the improvement team within Scottish Government would be extremely helpful.