What’s really going on with this virus.. & how worried should we be?
FLATTEN the sombrero, avoid a camel’s hump ... how do we make sense of all the Covid-19 graphs, charts and curves?
And what do they tell us about how bad things might get?
The University of Warwick’s Prof Mike Tildesley, an expert in mathematical modelling of infectious disease, says we can take heart that death rates are still low, even as the number of infections climbs.
Even in Bolton, the UK’s worsthit area, there are only two Covid patients in hospital.
Across all 18 areas in some form of lockdown, just 141 people are in hospital. Even with 4,000 new cases a day, it is still far off where we were in March and April, when an estimated 100,000 were ill.
Prof Tildesley warns against reading too much into Britain’s infection rate graph, or international comparisons.
He says: “The majority of testing used to be done in hospitals, and now there is a lot more testing in the community, healthier people with milder symptoms who probably won’t need hospital treatment.
“That explains the steep rise in infections – 3,000 cases a day today is not the same as 3,000 a day back in April, because we are doing so much more testing.
“It’s quite dangerous to compare one country to another in terms of their cases curves because it depends on how much testing you are doing.”
T h e younger , hea l thy p eop l e behind the rise in infections may in f e c t e lder ly , vulnerable relatives, leading to a rise in hospital admissions and deaths, but it is not inevitable, says Prof Tildesley.
He adds: “There’s some evidence of this in Spain. For a long time deaths remained low, but they’ve started to climb in the last few weeks. So we need to be cautious and keep monitoring that.
“But if deaths don’t rise, it will be because healthier people are getting infected and we are better at protecting the vulnerable.”
There is also the possibility that the virus has become less deadly.
Prof Tildesley says: “Viruses can mutate, and when they do they tend to mutate to milder forms, because it’s not beneficial for the virus to kill its host. That, and the fact better treatments are available may help reduce the death rate.”
Dr Christina Pagel, a professor of clinical operational research at University College London, and a member of the independent Sage group, is less optimistic.
She says: “It takes a week of you having coronavirus symptoms before it gets bad enough to go to hospital, and two or three weeks before you die, so there’s a lag between infection and death.
“We won’t see deaths going up for some weeks. It’s not enough to just protect the elderly. The median age of people currently in hospital with Covid in Birmingham and Manchester is between 45 and 55.
“It’s the parents of the young people who are getting infected.”
Dr Pagel believes the most important data is the number of new hospital admissions.
She says: “When I look at that, it makes me sad.
“On September 15, there were 194 admissions, with a seven-day rolling average of 154 per day. A week earlier, there were 84 admissions and a weekly average of 77. We’re on just over a week doubling time. At current rates of doubling we’re two weeks away from where we were on March 16, a week before lockdown, when we had just over 400 admissions a day.
“And there is no way that Test and Trace will be fixed by then.
“A week ago things were manageable, but now they are already getting out of control. That’s why I’m worried.
“As we are seeing more hospital admissions, we are definitely going to see more deaths, but I don’t think it will be as bad as in March. It better not be. WORRIED
A third of our deaths were in care homes, which is preventable.” Prof Tildesley doubts the Sage predictions of up to 250,000 UK deaths, pointing to the excess deaths, the number of people who have died this year compared to the average of previous years. After an increase in excess deaths at the start of the pandemic, by the summer deaths were below normal, suggesting many of those who died from Covid were vulnerable to other causes of death. He says: “We tend to get a
lot of excess deaths from seasonal flu in the autumn and winter, and it might be that, unfortunately, a lot of people who have died from Covid are the people who were most vulnerable to seasonal flu.
“This might mean we don’t see as many excess deaths from other causes before Christmas.”
He also points to the fact that daily deaths from coronavirus are still fewer than other causes, such as cancer, traffic accidents or even seasonal flu.
He says: “If we continue to see more people dying of the flu than
Covid, then it needs to be part of the discussion – we are getting more flu deaths, yet we don’t go into isolation because of flu.”
The US and Brazil still have daily Covid death rates in the hundreds, months into the pandemic. Prof Ti ldesley explains: “In the US, you’re not dealing with just one outbreak, but lots of outbreaks.
“Lots of states relaxed measures too early, and reintroduced them, prolonging the pandemic.”
Dr Pagel warns against complacency, saying: “We don’t know what the long-term impact of Covid is. For instance, 20% of flu patients are left with kidney damage after hospitalisation, but for Covid that’s 45%. And a study this week found that 85% of people who left hospital after Covid needed long-term health care. It’s very different to the flu.”
So why were we warned about hundreds of thousands of winter deaths? Dr Pagel says: “That prediction was based on everything being the same as the beginning of March. There are now many more restrictions which help reduce the spread.”
But she warns that, unless greater restrictions are brought in now, another nationwide lockdown is not far off.
She says: “Most of the transmission has taken place in pubs and restaurants, and people gathering in homes. These are the things we need to prevent.
“Countries that take decisions early before things get terrible have done the best. We have seen, in France and Spain, how waiting too long a second time can be equally disastrous. We need to act quickly.”