Category Archives: Medical

Health, Medical, Research, Science

Could a new ‘universal vaccine’ stop all strains of flu virus?

MEDICAL RESEARCH

A NEW universal long-lasting vaccine could prevent the need for yearly flu jabs.

Currently, scientists have to predict every year what the new strain of flu will look like, but by the time the vaccine has been made, the strain of virus may already have mutated and changed.

Recently released figures reveal the vaccine given to ten million over-65s, children and at-risk adults last year offered little protection against the killer H3N2 strain, known as Aussie flu, which put unprecedented pressure on the NHS during the winter months.

Public Health officials have admitted the jab had “no significant effectiveness” in preventing people from being struck down – and was deemed only 15 per cent effective overall.

UK researchers are now working on a “universal” vaccine to protect against a number of strains.

The cells of the flu virus are like spherical cushions with lots of pins sticking out. Flu vaccines currently work by triggering an immune response to antigens – the heads of the pins – on the cell’s surface.

The immune system creates antibodies, which are then primed to attack and block the real flu virus when it comes along: the antibodies recognise the virus by its antigens.

The new vaccine, developed at the University of Oxford, protects the body against flu in a way that makes it more universal.

 

SCIENTISTS have found that while flu strains vary, all flu viruses contain epitopes (parts of the antigen to which antibodies attach), which vary much less than previously thought. Targeting these epitopes through vaccination would protect against all strains of the virus.

The new vaccine is designed to home in on these common epitopes and help the immune system create antibodies to fight them.

So far they’ve identified specific epitopes for two main types of flu – influenza A virus (subtypes H1 and H3) and influenza B. Researchers say a vaccine using this new approach could provide immunity without the need for yearly vaccinations, and could work against many types of flu even if the virus mutates.

Two or three injections would give long-term protection against different strains, they say.

Sunetra Gupta, a professor of theoretical epidemiology who led the research, says: “We believe our methods can be applied to produce vaccines against all subtypes of influenza, thereby providing the opportunity to develop not only a more effective vaccine against endemic influenza, with lower healthcare costs, but also better protection against potential influenza pandemics.

“The same strategy can also be used to produce vaccines for swine and avian influenza, which will have significant economic consequences, and the control of which will reduce the probability of new lineages emerging with pandemic potential.”

Vaccination is the most effective way to protect against the virus and is given annually in the UK to people at risk, including the over-65s, children aged two to nine, pregnant women, and people in long-stay residential care homes.

But the problem with existing vaccines is that the flu virus frequently mutates in two ways.

The first, known as antigenic drift, involves small changes in the genes of influenza viruses as the virus replicates.

These small genetic changes usually produce viruses that are closely related to one another, and share the same antigenic properties, so an immune system exposed to a similar virus will usually recognise it and respond.

But these small changes can accumulate over time and eventually the immune system may not recognise them and respond.

The less common route is antigenic shift – an abrupt, major change in the influenza A virus, and most people have little or no protection against the new virus.

 

TO ENSURE vaccines are available when needed, six months before the flu season, scientists try to predict the new strain. However, as the latest figures show, they don’t always get it right.

Commenting on the research, Professor Wendy Barclay, the Action Medical Research Chair in Virology at Imperial College London, says: “There are lots of different ideas about to make a universal flu vaccine and how universal it would actually be.

“This work from the Oxford group would mean we don’t have to update the flu vaccine yearly, but if a new pandemic came along, chances are this type of vaccine wouldn’t work against that.

“But it would mean we don’t have to chase after the virus as it constantly drifts and we try to keep up.”

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Health, Medical, Research, Science

Blood pressure study linked to dementia

MEDICAL RESEARCH

A major study suggests that hundreds of thousands of people could be saved from dementia if blood pressure tablets were used more widely.

Researchers have shown for the first time that aggressively treating high blood pressure – particularly in middle age – could also significantly reduce the risk of dementia later on.

NHS officials are under growing pressure to lower the threshold at which people can be given the drugs, a policy that could make 14million eligible for treatment.

Patients are currently considered to have hypertension – or high blood pressure – only if they have a reading of more than 140/90 mm Hg.

But a study of 9,400 people in the US found cutting the systolic threshold – the higher reading – to 120 instead of 140 slowed cognitive decline.

An ideal blood pressure reading is between 90/60 millimetres of mercury (mm Hg) and 120/80. The first figure is the systolic pressure, the “surge” that occurs with each heartbeat. The second is the diastolic reading, which measures the pressure in the “rest” between heartbeats.

Using the new threshold over eight years reduced rates of dementia and mild cognitive impairment by 15 per cent, according to results presented at the Alzheimer’s Association International Conference in Chicago.

Similar trials have shown cutting the threshold for treatment would reduce the risk of heart disease by a fifth, and strokes by about a quarter.

Health watchdogs are already reviewing blood pressure guidelines with a view to cutting rates of heart disease and a decision is expected next year.

But they will now face greater pressure to change the rules after the new research, the first to look in detail at the impact of such a policy on dementia.

Study leader Professor Jeff Williamson, of the Wake Forest School of Medicine in North Carolina, said: “These results support the need to maintain well-controlled blood pressure, especially for persons over 50.”

A second study of 670 patients by the University of Pennsylvania found that the lower threshold also showed shrinkage of white brain matter, strengthening the link between blood pressure and dementia.

The US has led the way on blood pressure policy, lowering the treatment threshold in November from a systolic score of 140 to 130.

If the UK followed suit, it would mean an estimated 14million people – a third of all adults – would be eligible. Currently seven million are eligible.

A policy to increase this, however, would be controversial as it would affect many people who until now have been considered healthy. A similar change that lowered the threshold for cholesterol-busting statin drugs in 2014 led to a huge backlash, fueling accusations that health professionals were “over-medicalising” the middle aged.

A spokesperson for Alzheimer’s Research UK, said: “This study suggests treating high blood pressure intensively . . . may help to reduce the risk of memory and thinking problems.

“There is robust evidence that what’s good for the heart is also good for the brain and maintaining good vascular health is one of the key things people can do to reduce their risk of dementia.”

But Professor Clive Ballard, of Exeter University, warned: “All anti-hypertensives come with some risk of adverse effects, most seriously for kidney function.”

 

THOSE who feel light-headed when standing up after a long time sitting may be at a greater risk of dementia and stroke, according to a US study of more than 11,000 people.

Scientists at John Hopkins University found those whose blood pressure dropped when they stood up – a problem known as orthostatic hypotension – had twice the risk of suffering a stroke in later life. Their risk of dementia was 54 per cent higher.

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Medical, Research, Science

Breakthrough as vaccine is made possible for Multiple Sclerosis

MEDICAL RESEARCH

SCOTTISH doctors believe they have found the cause of Multiple Sclerosis (MS), paving the way for a vaccine against the devastating condition.

A landmark paper suggests MS develops following two separate common infections, which cause the body to attack itself.

Other factors, such as genetics and lack of sunlight, may also play a role, which explains why MS is more common in certain areas such as the North of Scotland.

But doctors behind the latest discovery believe the development of a vaccine against a common virus may hold the key in future prevention of the disease. The research was published by doctors from the University of Glasgow and Harvard University in the United States.

There are 11,000 Scots with MS, making the disease more common than in most other countries.

The neurological condition is triggered when the immune system, which normally fights infection, attacks nerves, causing pain, fatigue, vision problems and spasms.

But what causes the body to begin attacking itself has never been identified, despite more than 100 years of research.

It has been suggested the disease could be caused by lack of sunlight as it is more common in northern countries.

The latest research claims two common infections – firstly threadworms followed by the Epstein-Barr virus – may be the trigger. The scientists believe MS is a “rare complication” of the body’s response to the infections.

Professor John Paul Leach, consultant neurologist at the University of Glasgow, said: “MS is a condition where the body produces antibodies against itself for reasons that have never been understood and goes against its own nervous system.

“It is odd that we have never found out why some people are more prone than others.

“There is already some evidence that exposure to the Epstein-Barr virus makes it more likely someone will develop MS, but this does not offer the full explanation of why people develop this reaction.

“MS may be the result of not one but two infections in the right order.”

The research was led by Dr Patrick Kearns of the Chan School of Public Health at Harvard, who developed his theory while studying at the University of Glasgow.

Although keen to point out their hypothesis is only a theory, they now plan further research.

In MS, the immune system attacks the layer that surrounds and protects the nerves which damages them, meaning messages become slowed or disrupted.

Threadworms affect around one sixth of the world’s population and are a parasitic infection affecting the gut, common in children.

The Epstein-Barr virus is one of the most common viruses in humans and is the cause of glandular fever, although many people only suffer mild symptoms.

Dr Kearns said: “MS is a terrible condition but there is a fascinating aspect about it which is that its distribution around the world has been really well studied, so it’s easy to compare rates between regions.

“It also affects people when they are young, and rates are increasing, which means some aspect of the environment has to be changing that’s driving the disease.

“Some evidence has found high rates of MS in areas where there were military troops stationed in the Second World War, such as the Faroe Islands and Shetland.

“I believe the missing link may be threadworm infection. This is a very common condition in children and is also common in soldiers living in barracks. In areas where soldiers were billeted during the war it would have spread to local populations.

“There is already a strong and undeniable link between the Epstein-Barr virus and MS. I believe that what may be causing MS is a rare, late complication of exposure to these two infections.

“It may be a good idea for public health officials to treat worms at a population level. But the real benefit would be developing better tools to target the Epstein-Barr virus with a vaccine or drugs.”

Factors such as lack of sunlight or vitamin D have previously been suggested as triggers for MS.

But Dr Kearns believes the evidence for these is “not very strong” and does not fully explain the differences in MS rates around the world. However, he said some people may be more susceptible than others due to genetic factors.

There is currently no cure for the condition, but some treatments can slow its progress.

The research was first published in the journal Multiple Sclerosis and Related Disorders.

Dr Sorrel Bickley, head of biomedical research at the MS Society, said: “This study puts forward an interesting idea and we look forward to seeing how this could be proven or disproven.

“MS is unpredictable and different for everyone and we urge anyone concerned about symptoms to speak to their GP.”

 

MULTIPLE Sclerosis is a neurological disease that can affect the brain and spinal cord.

The condition’s symptoms are wide-ranging and can include problems with vision, arm or leg movements, sensation or balance.

In some cases, the disease can be mild but in others it can cause serious disability.

Average life expectancy is reduced in people with MS.

The immune system attacks the layer that surrounds and protects the nerves – the myelin sheath. This then damages and scars the sheath, and potentially the underlying nerves, meaning that messages travelling along them can become slowed or disrupted.

This can cause a range of symptoms including fatigue, difficulty walking, vision problems, numbness or tingling in different parts of the body and muscle stiffness and spasms.

Symptoms may come and go in phases, known as relapsing remitting MS, or get steadily worse over time.

Roughly between two and three women have MS for every man with the condition. In Scotland the rate is about 209 MS patients per 100,000 population compared to 164 per 100,000 in England.

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