Scientists have revealed the preliminary description of the bed bug’s sialome – proteins in the saliva that allows the bed bug to feed on humans without fatal retaliation.
Bed bugs belong to a group of parasitic insects that feed on blood. Their success in feeding undisturbed depends in part on the proteins in their saliva. These substances cause the host’s blood vessels to dilate to ease the flow of blood into its body, inhibit clotting and to prevent immediate pain and itching.
The immune system determines the host’s response to the proteins. Bed bugs can cause a number of health effects including psychological effects, allergic reactions and physical effects such as prominent blisters on the skin.
Common allergic reactions include the development of large wheal accompanied by itching and inflammation that can last for several days. Multiple bites may trigger blister-like eruptions. People with severe allergies may develop anaphylaxis. The allergens from bed bug bites are associated with asthmatic reactions.
Bite marks grouped in a linear pattern are suspected to be bed bug bites. Post-bite effect happens in 3 stages which include no reaction (development of few or no antibodies), delayed reaction; immediate and delayed reaction, immediate reaction only and no visible reaction.
Symptoms include raised and inflamed wheal at each bite site with intermittent itching for several days. Immediate reaction can happen within 24 hours of the bite and lasts for 1 – 2 days.
Delayed reaction to bed bug bites appear in 1 to 3 days followed by redness and periodic intense itching that may last up to 5 days. Delayed reactions may take up to 9 days before lesions appear.
Medical experts say people who receive frequent bites develop the sensitivity syndrome that includes nervousness, constant agitation and insomnia. Medical literature suggests a person may develop secondary infections from scratching the wheal and the bites can cause blister-like eruptions on the skin, anaemia and anaphylactic reactions and trigger or worsen asthma.
Sometimes bed bug bites develop into a hard whitish swelling that leaves a dark red spot surrounded by a reddened area. Bed bug bites usually fade after a while, but sometimes old bites flare up if the wound was not healed properly and the person keeps on scratching the wheal.
If you were bitten by bed bugs and you react adversely to the bite, you must take some steps to treat the wheal so they can heal. You should consult your physician immediately after you become aware of the bites, especially if you develop severe allergic reactions.
Home remedies and over-the-counter medications are available to treat the bites. People’s skin respond differently to treatments so please consult your doctor before using any home remedy.
(a) Treat the affected area with ice to soothe the wound
(b) Clean the affected area with an antiseptic soap (e.g. Dettol) before treating the wound. This prevents microbes from entering the wound. Rinse with cold water and apply a paste of coconut oil (1 tablespoon) and roasted turmeric powder (1 tablespoon). Leave the treatment on for 8 hours.
(c) Spray lavender oil on the wound for instant relief from itching. If you have an allergic reaction to the bites you can take corticosteroids. Please consult your doctor before doing so.
(d) Apply mint, garlic or cayenne pepper to the affected area after treating the wound.
(e) Black pepper, walnut and red pepper are useful herbs to treat the bites.
(f) Mix a tablespoon of salt and a tablespoon of baking powder and add water to make a paste and apply it to the wound.
(g) Apply a thick paste of cornstarch and water to the wound. Corn starch removes toxins in the affected area.
(h) Apply an astringent such as witch hazel, St John’s Wort or lemon juice to a cotton wool and dab at the wound to reduce itching.
(i) Apply rubbing alcohol to the affected area to relieve itching. Avoid scratching the wounds to prevent infections.
(j) Use a few drops of cedar wood oil with other medications (e.g. oral or topical corticosteroids and antihistamines) to treat the inflammation.
(k) Add concentrated peppermint oil, baking soda, oatmeal or Alka-Seltzer (only if you are not allergic to aspirin) to a warm bath and soak in it to reduce the itching.
(l) Honey and aloe vera can also treat the wound. The gel from the aloe vera plant has antifungal and antibiotic properties to treat the wounds.
(m) If you are not allergic to aspirin you can dip a cotton ball into Alka-Seltzer solution and apply it to the wound.
(n) Apply a light paste of aspirin mixed with water to the wound (if you are not allergic to aspirin).
(o) A hot wash cloth on the affected area can also relieve the itching.
Over the counter remedies
(a) Creams like cortisone ointment and calamine lotion reduce inflammation, itching and speed healing.
(b) Topical anaesthetics containing pramoxine relieves pain. Diphenhydramine soothes itching.
(c) Antihistamine such as Benadryl controls swelling.
(d) Hydrocortisone cream eliminates itching.
(e) Prednisone, an oral steroid, can treat itching. This medication needs a doctor’s prescription.
(f) Naproxen or Ibuprofen reduces swelling.
(g) Zyrtec and Claritin (oral antihistamines) are available over the counter to reduce allergic reactions.
(h) For systemic allergic reactions a doctor sometimes administers injections of antihistamines, corticosteroids or epinephrine.
(i) Your doctor may prescribe antibiotic ointments or oral antibiotics if secondary bacterial skin infection develops.
Bed bugs are not known to carry diseases, but they have significant public health importance. They carry at least 40 human pathogens including viruses, bacteria, protozoa and parasitic worms. Researchers have confirmed that these pathogens are not transmitted to humans through the bite.