What steps can you take to build your immune system while staying at home? Evelyn Ring talks to the experts.
Having a robust immune system is the best defence a person can have right now against Covid-19, says leading immunologist, Dr Anne Moore.
Dr Moore, an expert in vaccine immunology and infectious diseases, urges people to do as much as they can to keep their defences up.
She compares the virus to the floods in November 2009 that devastated Cork City and left hundreds of people in serious financial debt.
“The city [improved its] flood defences to protect itself and it’s the same for us. If we don’t put up a strong defence we are going to get overrun,” says Dr Moore from University College Cork.
Covid-19 is known as the silent virus because it can go unnoticed and undiagnosed in some people.
It can be more severe in people with cardiovascular disease or diabetes. But people, young and old, with no underlying condition, have died from coronavirus.
Moore is one of many scientists throughout the world who are trying to find a vaccine for Covid-19.
She leads a research group working with Vaxart, a biotechnology company in California, that is developing an oral tablet vaccine.
The vaccine contains a novel adjuvant that can induce a protective respiratory and system immunity.
Moore says the US company had already shown that the vaccine could be used to protect against influenza.
Her team is now helping the company develop the most potent platform for a coronavirus vaccine that could be available by the end of the year.
“If we had enough vaccines to give to healthcare workers by Christmas we would be doing really well,” she says.
In the meantime, the best line of defence is to stop the spread of Covid-19 and that might mean everyone having to wear a mask when they go outside their homes.
“It is a really miserable prospect but we are going to have to find some balance if people are to get on with their lives.”
The worst thing about Covid-19 was that it was a “silent” spreader, says Dr Moore.
Some cases of the coronavirus are asymptomatic, presymptomatic or mildly symptomatic. That was why testing and contract tracing was crucial in the absence of a vaccine or antiviral treatment.
“The virus is like the whack-a-mole game. We have got to whack the virus down as quick as we can and try and prevent other outbreaks from happening.”
Prof Catherine Stanton, a principal investigator at APC Microbiome Ireland and senior research scientist at Teagasc, emphasises the need for people to maintain a balanced and high-quality diet.
“This will ensure a diversity of the microbiome, which is linked to a better quality immune status, she says.
The body is full of trillions of bacteria, viruses and fungi. They are collectively known as the microbiome.
While some bacteria are associated with disease, others are extremely important for the body’s immune system, heart, weight and many other aspects of health.
Prof Stanton says it’s not known why some people infected with the virus became severely sick and others remained relatively healthy.
She had no doubt, however, that the immune system has a role to play in keeping people healthy and having a balanced and high-quality diet is the best way to maintain it.
Prof Stanton urges people to concentrate on their diet at this time so they can emerge in the best of health.
As well as having a role in the digestion of foods, gut microbes also make a variety of molecules that are important for physical well-being including vitamins B and K.
“Vitamins are vital to our health. We can’t make them ourselves so we have to get them from what we eat or from the microbes that produce them in our gut,” she says.
“The microbiome residing in the human gut is an important source of some of these important molecules and nutrients that we need for optimum health and development.”
But keeping the gut microbiome healthy means having a good spread of the right microbes in it and the best way to do that is having a balanced diet that includes plenty of fruit and vegetables.
A balanced diet is important as the body’s organs and tissue need proper nutrition to work effectively. Without good nutrition, the body is more prone to disease, infection, fatigue, and poor performance.
“A balanced diet will ensure diversity of the microbiome, which is linked to a better quality immune status,” says Stanton.
Only moderate amounts of meat and saturated fats should be eaten — the type of fats consumed influence the diversity of the microbiome.
“Eating omega-3 fatty acids that you can find in fish is good for the microbial diversity of the human gut,” she says.
Fibre, a complex carbohydrate, is also an important part of a balanced diet and is found in foods such as fruit and vegetables. It is food for the microbes, says Stanton.
“We do not as human beings have the enzymes that can break down the fibre in our diet, but, amazingly and interestingly, it is food for the microbes in the human gut because they have the machinery to break it down and utilise it as a source for themselves,” she says.
“Fibre promotes microbial diversity in the gut, which is a good thing, and it also promotes the activity and function of the microbes in the gut to produce beneficial compounds, such as short-chain fatty acids.”
Associate professor in the department of physical education and sport sciences at University of Limerick, Alan Donnelly, says there is very good evidence that being moderately active helps the immune response.
“Your immune system won’t prevent you from catching Covid-19. But it might defend your a little bit better if it is fully functional.”
But while a moderate level of exercise seems to be beneficial, really intense training has the opposite effect.
“Very intense training regimens seem to knock your immune system so it becomes less effective,” he says.
Donnelly says the 2km exercise distance imposed by the Government to contain the spread of the virus makes sense. It allows people to take regular, moderate exercise and it is good for their mental health.
People’s lung size vary, however this has nothing to do with how much training they do, he says.
“But you can ventilate better if you train. When you do any form of exercise you are breathing harder and the muscles in your chest and abdomen are moving in and out.
“You’d imagine that training would be a benefit for anyone who contracts Covid-19 but nobody knows that for sure.
“Common sense would suggest that it would be a benefit but there is no evidence we can use to back that up as yet.”
Researchers from Trinity College Dublin and Technology University Dublin have found that vitamin D can help build resistance to respiratory infections, including Covid-19.
They recommend supplementing a healthy diet with 20-50 micrograms per day of vitamin D as a short-term measure to address the risk of Covid-19 infection over the next three to six months.
As well as helping to build resistance to the coronavirus, vitamin D may help to limit the severity of the illness for those who do become infected.
Both the Irish Nutrition and Dietetic Institute and the Irish Society for Parenteral and Enteral Nutrition have adopted the findings.
Lecturer in human nutrition and dietetics at TUD, Dr Daniel M McCartney, says vitamin D deficiency is prevalent in Ireland.
In recent decades, exposure to a sufficient amount of sun has decreased and many people in Ireland may consequently have low blood levels of vitamin D.
“Supplementing a healthy diet with 20-50 micrograms per day of vitamin D represented a cheap, safe and potentially very effective protection for Irish adults against Covid-19,” says Dr McCarthy.