Janeane Williams, from Northampton, said she was terrified when she saw an enormous false widow spider in her home last week.
The false widow can bite if it feels threatened, and the venomous bite can result in burns and swelling, and possibly a fever.
A spokesman for Northampton-based exterminators Pest Professionals told the Metro: "There are many types of false widow and all though they look pretty scary they do not pose much of a threat to human beings. The species is actually scared of human beings but if cornered they could bite and cause a good deal of pain."
Conditions over the summer were reportedly perfect for the growth of false widow spider numbers, and now, with temperatures dipping to -7C in some parts of the UK, they're looking for some shelter.
Speaking to The Sun, pest management consultant Clive Boase said: "We've had a reasonably warm year with very few cold snaps and that has led to more invertebrates, such as flies, to feed on.
"Sightings of spiders often peak from September onwards as males of many species reach adulthood and venture into homes in search of a mate, and we could be seeing a lot more of them than normal over the next month or two."
They like to hide in window frames, under the sofa, in cupboards, lofts and garages, and even in clothes left lying around on the floor.
If you are bitten and notice any potential signs of infection, like weeping or swelling, contact your GP if it continues to get worse.
Tsetse flies may resemble house flies but these insects, found mostly in Africa, are blood suckers that carry dangerous parasites, causing sleeping sickness or trypanosomiasis. The disease develops slowly but can be fatal if treatment is delayed. Tourists on safari holidays in destinations, such as Tanzania and South Africa, as well as in the Sahara have been bitten by tsetse flies.
There's nothing scary about ants, right? Wrong! Fire ants attack humans with both a bite and sting, leaving your skin swollen, red and painful. While their sting is more bearable than a bee sting, fire ants have been known to kill people, especially those who are allergic. Native to South America and found in hot countries, the insects can cause victims who are allergic to their bite to sweat, have slurred speech and chest pain.
Known for carrying Chagas disease, Assassin bugs most often infect people in poor, rural areas of the Americas. They are known as 'kissing bugs' as they usually bite their victims around the mouth and nose while they are sleeping - some bites are painless and others are the most painful of any insect. The danger comes after the bite, with Chagas disease causing rashes, fevers and vomiting, and in some cases death.
You probably didn't think you'd find the common dust mite in our roundup of dangerous insects but when it comes to Britain's deadliest bugs, these tiny invertebrates that can only be seen under a microscope are the biggest killers. 90 per cent of asthma sufferers in the UK identify dust times as a trigger for their attacks and charity Asthma UK says there were 1,143 deaths from asthma in the Britain in 2010. While not all of these deaths were caused by dust mites, droppings left by the insects can trigger asthma attacks.
Malaria has killed millions of people worldwide and is most commonly transmitted by a bite from an infected female Anopheles mosquito. Once the female bites an infected human, she transmits the malarial parasites to the next person she feeds on. Dengue is another killer disease spread by mosquitoes, with experts warning travellers to Brazil for the 2014 World Cup of the risks when visiting the South American country.
They may be tiny but ticks can be deadly too. They feed on the blood of mammals and spread diseases between their hosts. The most serious for humans is Lyme disease, which if left untreated can cause permanent disability. In 2008, a British woman plunged to her death from her bedroom window after suffering from Lyme disease when she was bitten by a tick while staying at her friend's property in France. The tick bite caused Jan Lynton to suffer paranoid delusions.
The fact that Bull ants are found in Australia (where some of the world's deadliest and most venomous animals live) tells us their sting probably packs a serious punch. Also known as Jack Jumpers, they are one of the oldest ant species, grow over 40mm-long and are extremely aggressive towards intruders. They can spot you from a metre away and their highly painful sting can cause anaphylactic shock if you're allergic.
It may look cute and furry to some but the puss caterpillar is far from. The fuzzy creature, found in North America, will spit acid at any attacker and has poisonous pines all over its body, which can cause extreme reactions for humans. Although no deaths have been recorded as of yet, its sting is hard to identify leading to patients being misdiagnosed and sometimes accidental deaths.