DR ELLIE CANNON: At 73, is it possible I have developed Asperger's syndrome?

I'm 73 and I think I might have Asperger's syndrome. Since I was young, I have been picky about food and have always preferred my own company. Do you think I could have the disorder?

Dr Ellie replies: Doctors no longer use the term Asperger's but historically it refers to people who have 'high-functioning' autism – and it affects thousands in the UK, many of whom are undiagnosed.

People with autism find it hard to communicate and understand other people and social situations. They can have difficulties with too much stimulation, for example flashing lights and loud noises, which leave them feeling distressed. People with autism may repeat patterns of behaviour, doing the same routine over and over, like sticking to a specific walking route or eating only a certain brand of cereal.

Research suggests that about 750,000 people in the UK have undiagnosed autism

Crucially, many people with autism have learning difficulties, which mean they struggle to progress in school or, in severe cases, require full-time care. However, a significant number of people have a mild form.

They may struggle with social interactions, dislike loud places, or find that they become narrowly focused on a specific area of interest. But they do not have learning difficulties and are able to live successful, independent lives.

Research suggests that about 750,000 people in the UK have undiagnosed autism. Previously, people with mild autism – those who have a normal level of language and intelligence – were diagnosed as having Asperger's.

However, the medical world has moved away from this diagnosis because it creates the impression that Asperger's and autism are two different conditions, which they are not. There is no cure or treatment for autism – and it is not considered an illness.

But some people find that getting a diagnosis can be helpful because it allows them to better understand themselves.

Many people report that their autistic traits become more pronounced as they age, or are enhanced by other issues like grief or depression. Support groups and charities like the National Autistic Society can offer advice on topics such as communication, mental health and education. If you believe you might have autism, and you want a diagnosis, speak to your GP about an autism assessment. They should be able to refer you onto a psychiatrist.

My father, who is 89, had shingles 18 months ago and still suffers severe pain. He has been prescribed the painkiller pregabalin which seems to help a little. What else can he do to improve his pain?

Dr Ellie replies: Shingles is an agonising condition which, in some cases, can continue for months. It is triggered by a virus called varicella-zoster, which is also the cause of chickenpox.

The vast majority of people get chickenpox when they are children. However, even after the rash has cleared, the virus will remain in the body forever.

Usually this does not lead to any symptoms or illness however, the virus can reactivate later in life and this emerges as shingles.

Shingles usually appears as a band of rash, redness and blisters in a specific area of the body and it can be very painful. It most commonly affects people over the age of 65.

Unfortunately, for a fifth of patients, shingles can also trigger neuralgia – nerve pain that can linger for months.

Over-the-counter painkillers such as paracetamol and ibuprofen are usually ineffective against neuralgia, which is why GPs often prescribe specialist painkillers such as gabapentin, amitriptyline or pregabalin. If pregabalin appears to be working, then it may be possible to increase the dose.

However, this must be done under the careful supervision of a GP, particularly for elderly patients who are at risk of side-effects such as dizziness.

I'm a 75-year-old man and I have been told I will need a B12 injection every four months. Why are so many people low in B12 – and could there be any connection to Covid vaccines?

Dr Ellie replies: Vitamin B12 is essential for the body as it keeps our red blood cells healthy and ensures the nervous system functions properly. We mostly get B12 from animal products like meat, fish, milk and cheese.

This is why many people who follow a vegan diet – which does not include any animal products whatsoever – are advised to get B12 supplements.

However, the most common type of B12 deficiency is caused by something called pernicious anaemia. This is an autoimmune condition where the body wrongly makes defensive antibodies that attack the stomach and stop it from absorbing vitamin B12. Pernicious anaemia is most common amongst older people. One in ten Britons over the age of 75 are affected.

Given that the Covid vaccines were offered to people of all ages but vitamin B12 deficiency seems to primarily affect older people, it is unlikely that the jabs themselves have triggered a rise in the problem.