Coronavirus Q&A: Addenbrooke’s expert discusses how to help protect your family from Covid-19 this winter
Dr Matt Butler a consultant from the Covid Assessment Unit at Cambridge University Hospitals speaks with Alex Spencer about Covid-19, how it could spread in schools and offices as children return to their classrooms and workplaces reopen. And he discusses the steps needed to reduce the risks for children, teachers and families.
What will the impact be of reopening workplaces?
I think although you can spread asymptomatically, the big driver for infection is still people who are ill but are under some social pressure to still go to work. That's why I think it has been in meat processing factories because they are probably people on zero hours contracts and migrant labour. So not only are they working in close quarters they may be living with their co workers on site and there's a lot of pressure for them not to isolate or they may not know what the local rules are.
Air conditioning in offices is also a problem. Certain air conditioning units are worse than others. The ones you see commonly are those that suck in air at the bottom and just blow it back out; they are particularly bad for spreading this.
Should grandparents spend time with children?
If you are having a group of people in a house, I wouldn’t have an older relative there. That was a particularly important message when I did the Coronacast in Leeds because they have many more multigenerational families living in the same home.
That's why where we have seen the outbreaks in certain areas. It has been in those settings where we have lots of people mixing indoors.
Children don't seem to be the drivers of infection. If a kid is visiting grandparents it is more likely the parents will give them the virus because they will be talking to them at the same eye level while the kids play outside.
If we never get a vaccine or immunity doesn't last long people will start to have a more fatalistic approach because there are a lot of miserable old people out there who are not seeing their grandkids. We have seen a lot of people at hospital who have deteriorated from a positive perspective they are not seeing their family so there is that downside to their mental health
We haven't seen that much spread to older people in the countries that haven't closed down schools, I think because when they get it the children probably are less infectious. Also, grandparents mostly are still being careful. Older people who know they are much more at risks are still protecting themselves. It is also much safer to be above a child than at eye level so i think the height distance has played apart.
The big unknown is viruses behave very differently in different countries partly because of the environment they are in and because of how people behave. The only country ever affected in winter was China where their lockdown was punishable by criminal sanctions so people followed the rules to the letter and they were able to quash the virus much better than us.
I think how it behaves in winter will be a key test. If it turns out grandparents are catching it we may go back to them being shielded, but i think a lot of older people are still shielding themselves. My advice is grandparents should never take children to soft play indoors. If they are outdoors I think the risk is still very low.
My personal view is as long as someone knows the risks they make that choice themselves. My grandma died a couple of months ago and her attitude was I have an underlying illness which will take me at some point - and it did - so she wasn’t bothered about catching coronavirus. Individuals need to make that decision in an informed way. Age, above diabetes, obesity or being male is the number one risk factor.
The 80s represent half of all the deaths from the coronavirus. As long as they know that, it is up to them what they do with that information.
What did hospitals learn about controlling the virus?
I worked on the isolation ward at the peak of the pandemic where we received patients with suspected coronavirus and stratified them into ‘definitely have it’, ‘might have it’ and ‘definitely don’t have it’, and then we moved them into different paqrts of the hospital accordingly to stop it spreading.
That infection ward is still running. At the peak we were seeing 60 to 80 patients a day, which is what we would have in a peak flu season. The hospital has opened another assessment ward, so there is a huge increase in capacity for assessing patients.
At the start we didn't know about asymptomatic spread. Our figures at that time one in five of our cases actually acquired it in hospital. We did know the biggest risk was respiratory droplets. Those are the larger packets that you expel with normal talking and they decrease quickly in the air. Aerosol spread, however, would explain why people on flights can catch it four or five seats away. Aerosol may have spread down corridors and infected people further down the corridors.
Now we have learnt more, there have been a lot of changes to air flows on these wards. They have managed to change the air pressure on corridors to force the air out into the room where the patient is and then out of the window to outside.
Will the hospital cope with a second peak this winter?
There is a surge plan for if we do start to get more and more patients in. We have wards lined up, but it has massively impacted our capacity so we have gone down from 600 medical beds to high 300s or early 400s in total due to spacing. So the number of patients we can manage has gone down. That has had a big impact over the summer because we have been in ‘critical incident’ repeatedly over medical bed capacity. We have dropped capacity by about 30 per cent.
“You can look after fewer virus patients than other patients. It does depend on how much virus is circulating. We moved oncology out to the Nuffield which have moved back in now. We could move it back out again. There is also the Nightingale Hospital facilities in Norwich which could be reopened and I think we will get an additional 20 bed isolation ward for which we have applied for funding.”
Will reopening universities cause cases to rise?
Universities are the biggest concern in education because, unlike primaries or secondaries, universities are not geographically located. So you get lots of students travelling to them from all over the country mixing and potentially bringing in new strains and being in an age group where people are less likely to distance themselves.
Will there be a vaccine by Christmas?
There's a reasonable chance there will be one but it won't necessarily have a big impact until next winter. Do we vaccinate the people spreading it or the vulnerable? What we know from the flu vaccine is if you give it to the elderly they get less protection from the vaccine than healthy people. They don't generate such an immune response to it. So there will be a huge number of questions about how we deliver it and whether you have to repeat it so I think the impact won't happen next winter.
Is it worth losing weight before winter?
Even if you get a little bit fitter it can dramatically reduce your risk. It's all relative. If you go from smoking 20 a day to 10 a day it still helps. Any degree of weight loss or lifestyle change to make yourself that bit fitter is going to help. The people who get it really badly are overweight men who are also smokers. Bizarrely, smokers in one study appeared to be at lower risk but it seems that was because they were forced to go outside to smoke and weren't in the pub to catch it. They ended up being socially distanced because no one wants to be near them when they are smoking.
Changing lifestyle is never too late and you can reduce your risk. The other way to look at it is you can’t change your age, ethnicity or gender so the only thing you can do is change your diet and exercise habits.”
Will opening schools cause a huge spike in virus spread?
The greatest risk now is with children not going to school. I think there are risks of children not going to school to their mental wellbeing. We are at the stage that it is circulating in age groups that are less at risk but we want to keep it in low risk groups and not let it spread to the vulnerable.
At primary school the key thing is teachers and parents being careful at the school gates and for the school to follow a timed release where parents are spacing out rather than congregating. The virus could spread even outdoors if they are in a small space.
But school children are unlikely to be the drivers of infection. From what we understand now, children are not getting as sick as adults and spread the virus less. Whereas the people in intensive care and those who need oxygen are very infectious, children probably shed the virus for a shorter period of time because they don't have such severe symptoms.
How can school buses be safer?
If there isn't an alternative to using a bus, you have to do it in the safest way possible. The way to manage it would be to create good ventilation on the buses by opening all the windows to circulate the air. Maybe they could have more buses so each two seater is only occupied by one person. If they are on the bus less than an hour that would be a lower risk.
Will schools take part in testing?
The Department for Education has said schools can actively participate in testing. They won't be doing mass testing but they need enough for how many kids will get symptoms consistent with coronavirus. What will probably happen is they will be mistakenly testing people with colds. But this virus isn't really something that presents with cold symptoms or nasal discharge. What they should be on the look out for is the continuous cough, temperature and loss of taste or smell. However, kids don't tend to report loss of taste and smell so readily.
They have been given a number of tests but if they used them up they should be able to get more.
It would be good to encourage schools to take an active role in testing because the key to this is knowing quickly if someone is infected. There is always dead time; when the test is taken there is the transport time and when it gets to the lab you want it processed really quickly and have it back within 24 hours. From symptoms to test results should be a maximum of 48 hours, so if they are infectious you have got them isolated in that key period when they are shedding the virus.
What are the risks to school staff?
There are often questions on the Coronacast Zoom call I take part in for schools about pregnant staff or pregnant parents and then people that were in the shielding group that have been asked to work. In international studies, teachers were at a lower risk compared to other professions with a similar level of contact. The worst professions for catching the coronavirus were taxi drivers and security guards - probably because they were more likely to be middle aged men who were overweight, which put up their risk. I think schools have done distancing and handwashing really well and they are aware of the risks. If you think you are at risk you have won half the battle because you will change your behaviour to mitigate the risk.
I have managed to work in a high risk environment with positive patients and have managed to go five months without catching Covid. If they are with 30 kids in a classroom they can equally manage it, although they are not wearing PPE.
My own view is if masks don't have a negative impact I think it is a good idea for staff. When moving between classrooms it is a good idea to wear them and for teachers in staff rooms, too. They should probably not have staff meetings and do everything over Zoom. But if you are fit and healthy and young and keep ventilation going, that may be enough. The virus seems to be better controlled in countries where they regularly use facemasks like China and Korea. If it becomes natural behaviour to wear masks in schools maybe they will teach their parents to do so as well.
What will the number of cases be like this winter?
“I think we are going to be back in the same position we were with regards to cases. So the peaks will look the same. At the peak we were recording around 6000 cases of coronavirus a day but towards the end of March there were probably at around 100,000 cases a day, it's just we were not testing to any great degree.
Do we have enough tests and are they accurate?
At the start of the pandemic the hospital didn't have enough tests in order to say to people whether they definitely had the virus. And early on the tests weren’t that great either, so it took a long while to get accurate tests and for staff to learn how best to sample patients because it is key to perform it in the right way. Even if tests were negative early on we knew that they were actually positive. And so we were ignoring the tests
“I think the tests are much more sensitive now. So if you have an infection they will pick it up. But timing is key, so if you test a contact too early where they are not shedding the virus yet it wont show up on the result. If you say someone is negative it means they are not shedding the virus, but it doesn’t mean they are not infected.
That's why its probably not useful to test people flying back from Spain or Portugal because at that point they would probably still be in the incubation period and therefore negative and it wouldn't show up on a test. The worst thing is that person would be given a false sense of security and probably wouldn't quarantine because their initial test was negative.
What went wrong in care homes?
The key thing we need to do this time around is not to let it into care homes. I think we really did fail there. We were looking at Lombardy in Italy in the early weeks and seeing the hospitals there were overwhelmed. We didn’t want to get to the point where there was not enough space in the hospitals so we did make the decision to essentially pay for people to have residential home care. We normally wait for social services to foot that bill but this time the NHS just paid for them to have their ongoing care because they were waiting for discharge and we sent them to a care home.
“I did say we should be testing them but if we had tested them on discharge we wouldn't have tests available for the people who were coming into the hospital. So there weren't enough tests to go around. Even if I sent someone home and a test had been ordered the tests were being cancelled. When we introduced the commercial partners, the testing exponentially increased. But until that time we were down to 50k tests a day in the UK and couldn't do any more at Addenbrooke's. That equated to 30 or 40 tests a day and those tests were taking three days to come back, so they were not useful. The key thing is to know within 48 hours whether someone is infected so they can isolate themselves. If you don't know for three days if someone has an infection you have lost a lot of time.
Was Covid 19 here earlier than we thought?
It would be very difficult to prove. The earliest patient that was found was in February and they probably weren’t case zero. The statistical models only work if you put around 1,000 cases of coronavirus here at the end of January or beginning of February and that is certainly a lot earlier than we were testing.
At the end of February we certainly only detected nine or ten cases. We will never know how much there was, we were only testing patients coming back from Wuhan. The only time they have been able to prove there were cases earlier are when samples were kept back for another reason such as research or whatever and they have then gone back and tested. I'm sure there were people earlier. Some models suggest it was 100,000 cases a day at the end of March.
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