Donald Trump has clear risk factors – including his age, weight, and being a man – that all increase the risk of a serious coronavirus infection.
He is 74 years old and has a body mass index (BMI) over 30, which is the clinical definition of obesity.
So now he has tested positive for the virus, what does that mean?
At this point, Mr. Trump does not appear to be showing any symptoms.
But age is a clear and strong link with the development of a serious infection, leading to hospital treatment and, in some cases, death.
“But most people who get an infection also get better,” Dr Bharat Pankhania, of the University of Exeter’s medical school, told the BBC.
An initial analysis of over 100 studies, taking into account data from around the world, showed that the risk to children and young adults was minimal.
However, at age 75, it is estimated that one in 25 people who catch coronavirus will die. This figure rises to one in seven people over the age of 85 and one in four over the age of 90.
A similar pattern has been observed by the United States Centers for Disease Control (CDC).
It indicates that eight in 10 Covid deaths in the country have occurred among those over 65. And people in Mr. Trump’s age range are five times more likely to need hospital care and 90 times more likely to die than someone in their 20s.
It is not clear if the reason for this is something fundamental to being older, such as the immune system becoming less efficient over time, or if our age is simply a shortcut to being poorer. health.
“Age is also linked to heart disease, lung disease, and type 2 diabetes, so it’s difficult to determine if it’s their age or their co-morbidities (other health issues),” said Professor Ravindra Gupta, University of Cambridge.
Obesity has also been linked to more serious illness.
A review of the evidence by Public Health England concluded that being overweight increases the chances of requiring intensive care treatment and the possibility of death.
The fat in the body can influence the white blood cells of the immune system to increase the levels of inflammation in the body. Excessive inflammation is the reason the infection can turn fatal.
But again, obesity is linked to a host of underlying health issues, including type 2 diabetes and heart disease.
In the first wave of the pandemic, there were more men than women requiring hospital treatment, with 60% of deaths from Covid-19 occurring among men in the UK.
“There are immune differences between males and females,” said Prof Ravindra Gupta, which might explain the difference.
But again, men tend to be less healthy to begin with.
Professor Pankhania added: “We know that being male and older can lead to more serious illness, but it does not translate into serious illness for every elderly man. “
So what does this mean for Mr. Trump?
The problem is, it is dangerous to speculate on how the virus will affect a particular person.
All you’ve read is the big picture – a pattern seen across the population – that’s no way of saying that’s what’s going to happen to the US president.
The health of two 74-year-olds can be very different, and other medical conditions are massively altering the scale of the threat this virus poses.
It is not yet known if Donald Trump has even developed symptoms.
“Just because he has risk factors doesn’t mean he’s going to have symptoms, serious illness or die from the disease,” says Dr Nathalie McDermott of Kings College London.
She added, “He is also the President of the United States, so he has the best health care in the world if he feels unwell. ”
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