Britain is suffering a nationwide shortage of one of the two main vaccines — PPV23 — that helps prevent pneumonia, BuzzFeed News can reveal.

Some GP surgeries, which provide the pneumococcal jab, have run out completely and have not been informed when suppliers will replenish their stock, prompting patients to attempt to buy it from pharmacies.

But pharmacists at multiple branches of Boots told BuzzFeed News that they too have been out of stock for months, and had no idea when supplies will return.

One pharmacist at a central London branch said they hadn’t had PPV23 since November and have had to cancel appointments booked by members of the public at risk of pneumonia. A pharmacist at another branch said the problem was “everywhere”.

The PPV23 vaccine — which protects against the 23 most common strains of pneumococcal bacterium — is recommended for everyone over the age of 65, as well as people who live with a range of chronic conditions. For the elderly without health problems, a single dose can be given, but all patients with long-term conditions may need the jab every five years.

The vaccine is between 50% and 70% effective in preventing pneumonia, and therefore would help ensure patients in high-risk groups — such as people with HIV who are not virally suppressed — are not made more vulnerable to other infections, such as coronavirus.

Pneumonia has so far been found to affect 10% to 15% of patients hospitalised with coronavirus, although neither of the two vaccines available could have prevented these patients developing the life-threatening inflammation of the lung.

Dr Michael Brady, medical director of the Terrence Higgins Trust, Britain’s largest HIV charity, explained: “It’s slightly separate but interlinked — not having the pneumococcus vaccine doesn’t make you at any greater risk of getting coronavirus. It’s more about accessing any vaccination you can to reduce your risk of getting another chest condition, which if you got it, might make things worse for coronavirus.

"Everyone who’s got HIV who’s at risk of any chest infection should be able to access vaccinations that can protect them. It's bad that it's not available.”

Those most at risk of dying from coronavirus are the elderly and those with underlying health conditions.