What next with Covid? The crucial questions answered
Q&A
ANXIETY over coronavirus is rising along with the infection rate.
Here, Dr Mike Tildesley, an expert in mathematical modelling of infectious disease, and Prof Martin McKee, professor of European Public Health at the London School of Hygiene & Tropical Medicine, answer the key questions…
Q What’s really causing numbers to go up? Why are things worse in the North of England?
A The rising number of Covid cases is being driven by many different factors, according to Prof McKee.
He says: “Many depend on circumstances in each place.
“In some places, spread is mainly within households, but this is especially so when there are large numbers of people living in multigenerational homes. This is much less of a problem in, for example, Scandinavia.
“Clearly, universities are now becoming a focus for transmission in some places. “So are hospitality venues.” He believes some parts of England, particularly in the North East and North West, were too quick to reopen.
He says: “It does appear that the decision was made on the basis of national figures rather than looking at the regional differences.”
Q Is it true spreading is done by a small number of super spreaders?
A Yes, says Dr Tildesley. He adds: “Work done in India recently suggested that a very small percentage of the population is causing quite a lot more of the infections.
“It may be that those people are more infectious and more likely to pass infection on, but probably more that their job or circumstances bring them into contact with a greater number of people.”
Prof McKee adds: “A lot of the spread is at super spreading events, as illustrated perfectly last week in the Rose Garden of the White House.
“That’s why we need a really good system of backwards contact tracing.”
Q Is it really pubs and restaurants that are to blame?
A Dr Tildesley says: “I think it’s unfair to put all the blame on to pubs or restaurants, but it’s clear that in settings where mixing is high the risk is greater.
“Currently under the Rule of Six you could meet five people for breakfast, five for lunch, five for dinner and five for drinks, and they could all be different.
“So a balance of risk, going to a pub or restaurant, is a high-risk activity when compared with other settings.”
Q Why don’t the local lockdowns seem to be working?
A Dr Tildesley points out that the much more severe national lockdown “reduced the R number to below one, but only just”.
He goes on: “Local lockdowns have been having some effect but they aren’t taking the R number below one.”
Prof McKee blames the failure of the Government’s test-and-trace system, adding: “We have invested far too little in support for those who are isolating.”
Q If numbers keep going up after new restrictions are brought in on Monday, what might be the next step?
A
Another shorter national lockdown might be considered, especially if the NHS starts to become overwhelmed, believes Dr Tildesley. He says: “It might be a measure we have to take, but it’s a really difficult balancing act because of the effects on the economy and people’s wellbeing. It’s not an exit strategy or a solution but a short, sharp shock which might buy us some more time.”
Q Do we know more about how most people get infected? Do you have to spend a long time close to someone?
A Prof McKee says: “Yes, we know a lot more about the virus. In particular, we know that it is mostly spread through airborne transmission – aerosols that remain infectious when suspended in the air.
“While the initial advice about hand washing is still valid, it points to the much greater danger from being indoors in settings where there are large numbers of other people.
“This is why we need to think very seriously about whether bars and restaurants should remain open at this time.”
Q Some people are now saying that you don’t catch coronavirus from surfaces. How come?
A Prof McKee says: “It is still entirely possible to catch the disease from contaminated surfaces.
“It’s just that this is now seen as relatively less important compared with airborne spread, because there are more cases of airborne infection.”
Q What is the virus load? What effect does it have?
A Prof McKee says: “It does seem that people who are infected with a larger dose of the virus are more likely to get severe disease. However, there are many other factors involved, ranging from their genetic composition to their underlying health conditions.”
Q What’s the truth ruth about the number of people who are asymptomatic?
A Dr Tildesley y says: “This is one of the big unknowns.
Q What’s all the panic about if a vaccine for Covid is to start being rolled out next month?
A It’s because there is still huge uncertainty about how effective a vaccine will be and when one might be available, explains Dr Tildesley.
“Firstly, a vaccine will probably only be available in relatively small numbers, and it would take a really long time to ramp it up. Will it give everyone full immunity?
“Will it prevent infection or stop people getting symptoms if they do get infected?
“Will it be effective for the elderly? There are a lot of uncertainties.”
Q What has been the experience with schools?
A Dr Tildesley says: “There have been i isolated cases detected in schools, but often onl only one per school and those thos children or adults probably p got it somew somewhere else. The risk i in schools is extrem extremely low.”
Q Wh What is likely to hap happen when all the un universities in Britain are closed down for Christmas?
A Dr Tildesley says: “I don’t believe that students should be kept on campus, but I think we need to do what we can to make sure that the students can go home safely.
“We might need to consider an isolation period for students before they leave uni or after they arrive home, before they see vulnerable or elderly family members, so we can try to minimise that risk.”
Q Is it true we can be reinfected with Covid and get it worse a second time? And does that mean a vaccine would be ineffective?
A Prof McKee says: “It is certainly true that we can be reinfected.
“There is evidence immunity acquired by infection may not be so long-lasting.”
Dr Tildesley says the evidence suggests the disease might be less severe the second time around.
Q How does the UK’s second wave compare to other countries now?
A Dr Tildesley says: “We’re a little behind other countries, but the UK is somewhat mirroring the situation in France and Spain. Germany interestingly is not seeing the same kind of rise. Of course, our testing capacity is much better this time around, which muddies the waters in terms of comparing.”
Q Some are suggesting letting Covid spread among young, healthy people. Could herd immunity work?
A Prof McKee says there is no evidence herd immunity could be achieved. He adds: “In theory, if about 60% of the population were infected we might expect a degree of herd immunity.
“This is happening almost nowhere in the world, and even where it is, like in the Amazon, there is evidence that the immunity from infections, as opposed to vaccination, may be quite short-lived.”
Q What are the best and worst-case scenarios for next year?
A Dr Tildesley says: “The best case scenario of course is we have a vaccine that’s available in the very near future that we can mass-produce.
“The worst case scenario is we could have to deal with some level of restrictions for the foreseeable future.”