Many people are terrified of wasps, but although painful, the sting usually gets better by itself in a few hours. However, for some, it can lead to deadly anaphylactic shock.

Sean Hanrahan is one such person.

He said: “I had just sat down after work with my cup of tea to watch the Sopranos and then I was stung. Everything started to swell up. I live near my local A&E so I walked there, thinking I must stay calm.

“By the time I got there, everything was swollen and I could barely speak or breathe.”
Having an allergy to wasps or bee venom is rare and affects only around 0.4-3.3 per cent of the population. However, it can be fatal.

Symptoms include difficulty breathing, facial swelling, feeling faint and dizziness. It can lead to unconsciousness and death if it is not treated quickly enough.

As Sean works outside, it was really important to manage the risk of him being stung again, so his GP referred him to the Royal National ENT Hospital allergy service.

Every six weeks he goes to an allergy clinic to have wasp venom injected. Starting with a very small dose of venom, this is gradually increased to an equivalent of two to three stings. This helps reduce the risk from a future sting.

Sean said: “The doctor is brilliant. She explains everything and makes you feel relaxed. My last session is coming up and I will be celebrating with the team and patients.”

Dr Joanna Lukawska, consultant at the allergy clinic, said: “Sean’s experience is not unusual as most people are unaware they are allergic until they have a reaction.

“We test patients by replicating the situation in which they had a reaction. For example, one patient thought they were allergic to swimming pool water. We collected a sample of water. As they were exercising and therefore warm when they thought they had a reaction, we made sure they were also kept warm during the test.

“We try to make sure the clinic has a friendly atmosphere. Experiencing anaphylactic shock can be a terrifying experience so we want to reassure patients.”