Although many of us are enjoying the balmy temperatures of this year's heatwave, unfortunately for some, biting insects are flourishing too.
Calls to the NHS helpline 111 about insect bites are almost double the rate they normally are at this time of year.
And senior doctors are reporting incidents of patients being treated in hospital for infected horsefly bites.
Despite the heat, experts say standing water, such as garden paddling pools, where insects thrive should be removed.
Dr Nick Scriven, president of the Society for Acute Medicine, said: "We wouldn't normally see anyone coming to hospital for a bite, but we have seen a few recently needing treatment with antibiotics which is very unusual.
"A couple of these were infected bites from horseflies. They actually give one of the nastier bites, because they take a chunk out of you.
"They can be very painful, and can take a while to heal, and as result can get infected and need antibiotics. In the worst-case scenario, they can cause cellulitis, an infection of the skin."
According to Public Health England data on calls to NHS 111, about 9,000 people called the helpline on 8 July, around double the baseline figure which is constructed from historical data.
This chimes with the Met Office records of the heatwave. Although most of June and July was warm, temperatures peaked between 24 June and 9 July when 28 degrees was recorded somewhere in the UK every day. This happens on average only twice a decade.
Prof Adam Hart, an entomologist at Gloucestershire University, said that anecdotally horseflies were on the rise, although there is no hard data to confirm this.
"We had a wet spring, then we've got this beautiful hot weather which are great conditions for a lot of different insects to thrive in."
Dr Daniel Whitmore of the Natural History Museum's insect division agrees: "Horseflies like hot weather in general, so they may become more active around breeding sites and farms in hot weather.
"Obviously, by wearing fewer clothes in hot weather we expose ourselves to bites more and become more attractive to the flies.
"From personal experience I've noticed that the likelihood of being bitten increases after a dip in the pool (or stream or river): the wet skin probably helps the flies detect us."
But whereas most bites are relatively painless and clear up quickly on their own, the horsefly bite is noticeably more painful and more likely to get infected.
Natalie Bungay, from the British Pest Control Association (BPCA) is advising the public to be pest aware.
"Horsefly bites are particularly painful because their main food source is livestock, which have a limited ability to move the fly away.
"This means they can take their food without having to worry about delivering a painful bite, as the animals are generally powerless to stop them.
"This is as opposed to mosquitoes, which extract blood through a painless bite."
As horseflies and mosquitoes rely on wet and marshy areas to breed, the BPCA is advising the public to remove standing water from near their homes, where possible.
If bitten, Dr Scriven advises paracetamol and calamine lotion to reduce itching.
After a horsefly bite, the advice is to seek medical attention if the skin starts to get red and you develop a fever.
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