From brain swelling to stroke and killer infections – how chickenpox can prove fatal as new NHS jab offered to millions
CHICKENPOX has gained a reputation as a ‘harmless’ childhood illness that it’s best to get over with – but it could result in dangerous complications for some and may even prove fatal.
It was announced that children will be given chickenpox vaccines for free on the NHS for the first time from January 2026.
The jab is already used in the US, Canada, Australia and Germany.
One to three-year-olds in the UK will receive the chickenpox vaccine along with the measles, mumps and rubella (MMR) jab.
The combined vaccine will now be dubbed MMRV, as it will protect against the varicella zoster virus.
Responding to news of the chickenpox vaccine rollout in the UK, Dr Gayatri Amirthalingam, from the UK Health Security Agency, said: “For some babies, young children and even adults, chickenpox can be very serious.
“It is excellent news that we will be introducing a vaccine. It could be a lifesaver.”
The news was coupled with warnings from experts that nearly one in five school-starters are not fully protected against preventable diseases – with uptake for the four-in-one diphtheria, tetanus, polio and whooping cough booster and MMR jabs having dropped again.
Chickenpox is a highly contagious infection known for its telltale itchy, spotty rash that blisters and scabs over.
But before these spots appear, the virus can also cause a high temperature, aches and pains, and loss of appetite.
Though it’s mostly known to infect children, adults can also catch chickenpox if they didn’t pick it up in childhood.
These infections tend to be more severe and adults with a varicella infection are more likely to be admitted to hospital.
Most people will recover on their own within a week or two, but the infection can be serious, even life-threatening, for some – especially if they’re very young or old, pregnant or have a weakened immune system.
The illness can result in bacterial skin infections and in rare cases, pneumonia, brain swelling and stroke.
For some, these complications can be fatal.
An average of around 20 people die of chickenpox per year, according to the Vaccine Knowledge Project at the University of Oxford.
This ranges from 17 deaths in 2017, to four in 2020, according to Office for National Statistics data.
Eighty per cent of deaths from chickenpox infections in England and Wales occur in adults, the National Institute for Health and Care Excellence (NICE) states.
1. Bacterial infections
Chickenpox spots can appear anywhere on the body – including inside the mouth and around the genitals.
They tend to develop into fluid-filled blisters, before bursting and scabbing over, which can take a few days.
The spots tend to be maddeningly itchy, so it can be hard to resist the temptation of scratching them – though soothing creams and cool baths can help.
Chickenpox symptom timeline
The main symptom of chickenpox is an itchy, spotty rash anywhere on the body.
Before or after the rash appears, you might also have:
- A high temperature
- Aches and pains, and generally feel unwell
- Loss of appetite
Chickenpox happens in three stages, but new spots can appear while others are becoming blisters or forming a scab.
Stage 1: Spots appear
The spots can:
- Be anywhere on the body, including inside the mouth and around the genitals, which can be painful
- Spread or stay in a small area
- Be red, pink, darker or the same colour as surrounding skin, depending on your skin tone
- Be harder to see on brown and black skin
Stage 2: Spots become blisters
The spots fill with fluid and become blisters. The blisters are very itchy and may burst.
Stage 3: Blisters become scabs
The spots form a scab, some are flaky, while others leak fluid.
It usually gets better on its own after one to two weeks without needing to see a GP.
Source: NHS
Sometimes the chickenpox spots can get infected with bacteria – probably from scratching, according to healthcare provider Bupa.
Signs of a bacterial infection include a high temperature and redness and pain around the chickenpox spots.
You should seek urgent medical help if you or your child develop these symptoms.
2. Dehydration
Young children do run the risk of becoming dehydrated due to chickenpox.
For babies and kids, fewer wet nappies and peeing less can be telltale signs of dehydration.
Other signs may include:
- Feeling thirsty
- Dark yellow, strong-smelling pee
- Feeling dizzy or lightheaded
- Feeling tired
- A dry mouth, lips and tongue
- Sunken eyes
Call NHS 111 if you suspect you or your little one are dehydrated from chickenpox.
3. Pneumonia
Some people – especially adults – can develop pneumonia, inflammation of the lungs, after being infected with chickenpox.
Pneumonia is the most common chickenpox complication in adults, according to NICE.
Smokers are particularly at risk.
Symptoms of pneumonia can include:
- A cough with yellow or green mucus
- Shortness of breath
- A high temperature
- Chest pain
- An aching body
- Feeling very tired
- Loss of appetite
- Making wheezing noises when you breathe
- Feeling confused
4. Brain swelling
Infection or swelling of the brain, known as encephalitis, is a rare complication of the chickenpox infection.
Professor Benedict Michael, Institute of Infection, University of Liverpool, said: “Varicella-zoster virus is the second leading cause of brain infection (or ‘encephalitis’) in the UK, which can be life-threatening.
“Early diagnosis and treatment are essential, but prevention through vaccination is the most effective way to protect children and families from this serious complication.”
Dr Ava Easton, Chief Executive of Encephalitis International, added: “By making [the chickenpox vaccine] available to every child, we’re not only reducing the spread of chickenpox but also helping to stop some families from ever facing the devastating impact of encephalitis.
“That’s a powerful step forward for children’s health and for awareness of a condition too few people know about.”
Encephalitis usually starts off with flu-like symptoms, such as a high temperature and headache.
More serious symptoms develop in the next few hours, days or weeks, including:
- Confusion or disorientation
- Seizures or fits
- Changes in personality and behaviour
- Difficulty speaking
- Weakness or loss of movement in some parts of the body
- Loss of consciousness
Dial 999 for an ambulance immediately if you or someone else has these serious symptoms.
5. Stroke
According to the Stroke Association, children who develop chickenpox may have a four times higher risk of stroke in the six months following infection.
“However, stroke in children is still rare and the finding translates into a very small actual increase in their stroke risk,” it noted.
Studies by the organisation also found that adults with shingles – also caused by the varicella zoster virus – may also have an increased risk of stroke up until six months afterwards.
“This is particularly within the first few weeks, and for individuals with shingles around the eye,” Stroke Association said.
“Oral antiviral drugs used to treat shingles may be able to reduce this risk.”
What are the symptoms of stroke?
The FAST method – which stands for Face, Arms, Speech, Time – is the easiest way to remember the most common symptoms of stroke:
F = Face drooping – if one side of a person’s face is dropped or numb then ask them to smile, if it’s uneven then you should seek help.
A = Arm weakness – if one arm is weak or numb then you should ask the person to raise both arms. If one arm drifts downwards then you might need to get help
S = Speech difficulty – if a person’s speech is slurred then this could be a sign of a stroke
T = Time to call 999 – if a person has the signs above then you need to call 999 in the UK or 911 in the US for emergency care.
Other symptoms include:
- sudden weakness or numbness on one side of the body
- difficulty finding words
- sudden blurred vision or loss of sight
- sudden confusion, dizziness or unsteadiness
- a sudden and severe headache
- difficulty understanding what others are saying
- difficulty swallowing
6. Sepsis
In rare cases, chickenpox can result in sepsis – when the body’s immune system overreacts to an infection, attacking its own tissues and organs.
Sepsis can be life threatening and requires immediate medical help.
It can also be hard to spot, as there are lots of possible symptoms.
In adults, remember the SEPSIS acronym:
- Slurred speech or confusion
- Extreme shivering or muscle pain
- Passing no urine (in a day)
- Severe breathlessness
- It feels like you’re going to die
- Skin mottled, discoloured, or cold
Other signs include:
- High or very low body temperature
- Rapid heart rate
- Low blood pressure
- Rapid breathing
In children, look out for:
- Fast breathing
- Lethargy or difficulty waking up
- Mottled, pale, or bluish skin
- Very cold hands and feet
- Seizures
- A rash that doesn’t fade when pressed ,which is a sign of meningococcal sepsis
- Babies not feeding or vomiting
