Britain’s coronavirus death rate is falling, but the unanswered question is why | Charlotte Summers | Opinion

WWhy has the coronavirus death rate fallen in the UK? The National Critical Care Audit and Research Center analyzed data from more than 10,000 patients admitted to intensive care units in England, Wales and Northern Ireland, and showed that 28-day mortality of patients admitted to intensive care had increased from 43.5% by April. peak at 34.5% after peak – a decrease of nine percentage points.Some have suggested that this could be due to “herd immunity” or that over time we have learned how to successfully treat this disease. But there is little evidence to back up these claims. So what’s going on?

Emerging data suggests that some people who have not been exposed to Sars-Cov-2 have a type of white blood cell (T cell) that recognizes the virus because it has already been exposed to other coronaviruses, such as the common cold. It is not yet known whether these cross-reactive T cells prevent or lessen the impact of infection in people with coronavirus. This is an interesting preliminary finding, but there is currently no evidence that we enjoy collective immunity in the UK.

Studies have consistently shown that less than 20% of the UK population has antibodies to the coronavirus in their blood, and we do not fully understand the mechanisms by which our immune system effectively processes this new virus.

The term collective immunity is ill-defined and unnecessary. This suggests that we can now relax our adherence to measures such as social distancing and facial covers. But this is not the time for complacency. We are heading into a winter that is likely to be difficult, and we all need to continue to do our part to reduce viral transmission. The most likely contributor to the decrease in mortality is the same reason we have seen a reduction in the number of Covid cases: the British population has embraced social distancing, wearing face blankets, working from home and regular hand hygiene.

Are we better at dealing with Covid-19? As much as I would like to say yes, my answer is “not sure”. Many clinical management approaches have been proposed for the coronavirus, such as hydroxychloroquine, ventilation non invasive and vitamin supplements, and a lot to have suggested that given the urgent need for treatments, we should use them as soon as possible. This has led to patients around the world receiving therapies for which there is little evidence of benefit.

During the pandemic, there was immense pressure to bypass our usual avenues of safely discovering treatments. When faced with a devastating disease, the urge to act quickly to find new interventions is not surprising. The controversy surrounding hydroxychloroquine is a good example. Despite mounting evidence that the drug is not effective in treating people who have developed Covid-19, or in preventing the development of the disease in people exposed to the virus, people in countries like the Brazil and the United States continue to receive this treatment. .

There were also many questions about the best way to support people who have difficulty breathing. Many people said their approach was the right one, but there is currently little evidence to suggest that non-invasive ventilation is superior to invasive mechanical ventilation when treating patients with severe cases of Covid-19.

The use of unproven therapies outside of clinical trials should be of concern to us all and has been actively discouraged by Chief Medical Officers in the UK. There is no drug or therapy that does not have side effects or unwanted consequences, so every time we take this approach, patients are at risk in the absence of evidence.