Red spots on the arms, legs and face could be bites from bed bugs. These parasites feed on human blood. Their bites may be itchy but are harmless. Read on to find out how to get rid of them.
At a glance
- Bed bugs are small parasites that feed on human blood.
- Bedbug bites cause itching. While this makes these parasites bothersome, they are harmless.
- Bed bugs do not transmit disease.
- Bed bugs spread through contact with infested clothing, luggage or mattresses and bedclothes.
- Their bites can be easily confused with insect bites or flea bites.
- There are various treatments to get rid of bed bugs.
Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.
What are bed bugs?
Bed bugs are oval, flat parasites that are just five millimeters in size. Bed bugs like the dark. In the daytime, these brownish insects hide in dark places, such as mattresses and bedclothes or cracks and crevices. This makes them difficult to find.
At night, bed bugs crawl over sleeping humans and feed on their blood. Their bites sometimes itch and can become inflamed. However, bed bugs do not transmit disease.
Bed bugs go through six stages of development from egg to adult insect. They need a meal of blood every 3 to 5 days to do this. They can multiply and spread very quickly.
What are the signs of bed bug bites?
People often don’t notice that they have been bitten. One reason for this is that bed bugs bite at night when the person is sleeping. Another reason is that the bed bug numbs the site of the bite.
The following symptoms may indicate a bite from bed bugs:
- itchy bite sites or wheals, especially on the arms, legs and face
- sometimes three bites directly beside each other
- itching, which often only starts a few days later
- fitful sleep
- blood stains on bed sheets
- black and brown stains (bed bug feces) on mattresses
- a strong smell emanating from the bed bugs
Where do bed bugs come from?
Bed bugs are typically transferred via clothing or luggage. Any bed bugs hiding in mattresses or other pieces of furniture also find their way to humans.
The risk of coming into contact with bed bugs is particularly high in accommodation that is used by lots of people, such as a youth hostel. It’s also easier for bed bugs to find someone to bite when lots of people live closely together.
How common are bed bugs?
Bed bugs are common all over the world. These parasites are able to spread because people travel the globe.
What can be done to get rid of bed bugs?
As bed bugs hide themselves during the day, they are often difficult to find. Small dark spots (bed bug feces) or blood stains on bedding indicate an infestation.
Those who bring used mattresses, clothing or furniture into their home should check them for signs of a bed bug infestation.
Bed bugs die at a temperature of around 50 degrees and above. Clothing or bedding should therefore be washed at a suitably high temperature.
Effective means of repelling bed bugs by simply using a certain smell (i.e., a repellent) are not yet known.
Items that cannot be washed should be heated to over 50 degrees for at least 2 hours or frozen at minus 5 degrees for at least 5 days.
Those who are sleeping away from home should check things like bedding, mattresses and furniture near the bed for the presence of bed bugs.
How are bed bug bites diagnosed?
People initially notice red spots on the arms, legs and face on waking. These are bite marks from bed bugs. There are often two or three bites directly beside each other.
The bites may be itchy but this isn’t always the case. Sometimes the itching only begins days later.
Important: Bites from fleas, mites or mosquitoes can be confused with those from bed bugs.
Other possible reasons for itching and red spots on the skin include allergies, eczema, chickenpox or bacterial infections such as impetigo (Impetigo contagiosa). These need to be ruled out by a doctor.
The diagnosis is absolutely certain if bed bugs are actually found.
How are bed bugs and their bites treated?
Those who discover bed bugs in their own bed should act fast so that the parasites do not multiply and spread any further.
The main steps to take immediately include:
- disposing of heavily infested mattresses or furniture
- washing bedding and clothing at a minimum temperature of 60 degrees and drying them in a dryer at a high temperature
- cleaning less infested furniture and floors with a vacuum cleaner
The house and furniture can also be treated with insecticides, but this should always be left to a professional. That’s because proper, professional treatment minimizes any risks to health, e.g., from poisoning. After 4 to 20 days, the treatment should be repeated to ensure that all bed bugs are actually caught.
Treatment with heat can also be carried out. In this case, the infested rooms are sealed up by professionals and heaters are set up to heat the rooms at more than 50 degrees for at least 48 hours.
In many cases, bed bug bites and hives don’t require any treatment. They usually disappear after about a week. If the bed bugs have bitten a person repeatedly, the bite sites may itch more. Non-prescription or prescription-only products such as cortisone ointments relieve the itching. Used once to twice daily for 7 days, they promote healing of the affected areas of the skin.
- DynaMed (Internet), Ipswich (MA). Bed Bug Bites. EBSCO Information Services. Record No. T900607. 2018 (1995). Aufgerufen am 02.03.2021.
- UpToDate (Internet). Bedbugs. Wolters Kluwer 2020. Aufgerufen am 02.03.2021.
- UpToDate (Internet). Insect and other arthropod bites. Wolters Kluwer 2020. Aufgerufen am 02.03.2021.
- UpToDate (Internet). Prevention of arthropod and insect bites: Repellents and other measures. Wolters Kluwer 2020. Aufgerufen am 02.03.2021.
In cooperation with the Institute for Quality and Efficiency in Health Care (Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen) (IQWiG). As at: