Bed bugs tend to feed at night but will search for a host at any time if they are starved. They find a host through an array of sensors that can detect warmth, carbon dioxide and body odours.
Bed bugs feed for only 5-10 minutes until they become engorged with blood, if not disturbed and may spend less than 20 minutes on a host. After feeding, they return to their shelter.
How to spot bed bug bites
Small, flat, raised bumps on skin.
Several bites tend to appear in a line or row along an exposed area of the skin. This is usually the arm or leg.
Several groups of bed bug bites around the body could indicate multiple bed bugs feeding.
How to treat bed bug bites
Bed bugs do not carry diseases so the only treatment needed is to stop itching and rarely for inflammation. If the bites develop into very itchy bumps, general products available from a pharmacy to stop itching are suitable. For inflammation it is best to see a doctor who can prescribe the most suitable treatment. Many people do not react to bed bug bites so do not need any treatment.
How to prevent bed bug bites
If you are worried about bringing back bed bugs from your travels, then follow these steps to prevent bed bugs from entering your home and feeding upon you at night:
Leave luggage in your garage or bathroom. Bed bugs don’t like tiles or concrete, and it is easier to spot them on a hard surface compared to carpet.
If you are really worried take off your clothes in the garage or bathroom and place them straight into the wash.
Wash and dry clothes on the highest possible temperatures. Bed bugs don’t like heat.
Vacuum your home, and your furniture thoroughly. This will reduce the size of your bed bug problem by eliminating both the adults and the eggs.
Worried about bed bugs in your hotel or dorm? Follow these steps to prevent them from biting your guests:
Train staff on how to identify bed bugs.
Ensure thorough checking for bed bugs is part of your room cleaning process.
Midges and gnats
The term midge and gnat is a very general term for a wide range of flies, including the Sand fly and Black fly. Most are aquatic during the larval stage.
It is important to note that not all flies bite, some go about their day to day lives without the need to feast on humans. However there are a few fly species which rely on our blood to survive, these are:
How to treat fly bites
Wash the bite with soap and warm water.
Use and apply either antiseptic cream or spray to the area after washing.
Apply ice to the bite for 15 minutes, several times a day.
Avoid scratching so you don’t break the skin and cause and infection.
The bites of some flies such as horse flies can bleed. In this case a simple plaster applied after the bite has been washed would help. If the bleeding doesn’t stop on its own, you should see a doctor.
How to prevent fly bites
Avoid outdoor activities during the day when flies are more prevalent.
Cover up — wear long sleeves when outside.
Use an insect repellent before going outside.
Empty out bins, and clean dirty cups and plates regularly — flies are attracted to decaying matter.
Install window and door screens to keep flies out.
The head louse, or nit, is a single species of small wingless insect, Pediculus humanus capitis, which feeds only on human blood and has its complete life cycle on the human scalp.
Lice cannot jump or fly but can crawl from person to person in close contact. Head lice commonly affect children, but anyone with hair can catch them.
Head lice are considered harmless as they are not known to carry any disease and are regarded more as a cosmetic problem. They do cause itching of the scalp and secondary infections can result from scratching.
Adults are up to 3mm long and grey in colour until they have fed on blood, after which they become reddish.
The females lay 3-4 eggs per day near the base of a hair shaft, gluing the eggs to the hair.
The eggs are oval and less than 1mm in length. They are transparent until hatched, after which they appear white. The eggs hatch in 6-9 days and the shell stays attached to the hair.
The six legs of the louse each have a claw on the end to grab onto hair.
Detecting head lice
They are commonly found in the hair behind the ears and at the nape of the neck.
The remains of the white egg cases can also be seen attached to hairs.
The lice can be combed out of the hair onto a piece of white paper using a special nit comb that has very closely-spaced teeth to trap the lice.
Treating head lice
Repeated use of a nit comb can remove the lice, but larger infestation may only be effectively removed with medicated shampoos or lotions available from pharmacies. These contain insecticide so should be used carefully, especially on children.
The body louse (Pediculus humanus humanus) is indistinguishable from the head louse, but lives mainly in clothing, so the two types do not interbreed under normal conditions.
They are thought to have evolved from head lice around 100,000 years ago, which is about the time when humans invented clothing.
The adults are 2.5-3.5 mm long with six legs and grey body.
Eggs are laid on clothing and the skin, being found mainly around the waist and armpits.
The adults must regularly feed on blood and will die in a few days at room temperature if away from a host.
Prevention and treatment is to wash infected clothing at high temperature or destroy it.
The body louse can spread the rickettisal diseases Epidemic typhus (Rickettsia prowazekii) and Murine typhus (Rickettsia typhi). Epidemic typhus has been responsible for millions of deaths throughout history especially in time of war among soldiers and prisoners.
The house dust mite does not feed directly on humans but on shed skin particles and pet dander. The shed skins and faeces can cause allergic reactions in some people, similar to hay fever, asthma and eczema.
The scabies mite, Sarcoptes scabiei, is a parasitic mite about 0.5mm long that burrows into the outer layer of skin to feed on skin cells. It lays 10-25 eggs that hatch and emerge from the skin after 3-4 days to travel to another part of the body and repeat the cycle.
The infection results in itching caused by the body’s reaction to secretions from the mites. This can take up to eight weeks to appear.
Scabies is highly contagious. People living in the same household are likely to become infected easily.
The most common treatments for scabies are the pesticides permethrin, malathion and lindane. However, these can have side effects and should be used with advice from a medical professional.
Rickettsialpox is caused by the bacteria Rickettsia akari, which can be carried by house-mouse mites. They will seek new hosts, including humans, when the mice die off naturally or as a result of pest control. Infection is transmitted by the bite of the mite.
Rickettsialpox is regarded as a mild disease that takes 2-3 weeks to recover from. The first symptom is a bump around the bite that appears about a week after the bite, which turns into black crusty scab.