• Rosa Taberner, dermatologist

    What bit me?

    25 May What bit me?



    The Journal of Family Practice

    Bites from insects can represent a real health problem for both children and adults. Besides the fact that these pesky creatures can transmit diseases (malaria, yellow fever, tick-bite fever, leishmaniasis, etc.), the main problem is almost always the bite itself. In some cases, due to the intensity and suddenness of the reaction, it's easy to determine the cause (a bee, wasp, horse fly, scorpion, etc.), but in others, when the reaction is delayed, the cause may not be so obvious.


    Mosquito bites are one of the worst things about the summer. Mosquitoes are found mainly in hot, humid areas, and around swamps and lakes. Doctors see a lot of patients about mosquito bites, especially people with inflammatory and allergic diseases, who are more susceptible to the effects of a bite. Female mosquitoes need a blood meal to ensure their eggs are fertile. The symptoms of a mosquito bite appear almost immediately and are easy to spot: redness, swelling and itching, and it's common for some people to have many bites.


    Besides the discomfort from their bites, some species of mosquito are also vectors of infectious diseases (in endemic countries), such as malaria, leishmaniasis and yellow fever. Cases of bites from the Asian tiger mosquito in some areas of the Mediterranean Basin have been reported since 2004. Bites from these mosquitoes are more painful and last longer than those from other kinds of mosquitoes.


    Flea bites: three at a time

    When it comes to fleas, the diagnosis is not so obvious, since the skin reaction usually takes longer to show and many people don't connect the sores with insect bites, which can create a real challenge for doctors.


    Fleas are blood-feeding insects. They don't have wings, but can jump considerable heights. They can also transmit different diseases (such as bubonic plague and murine typhus) and their saliva can produce ugly sores that itch a great deal. The sores have a single point in the centre and are typically arranged in a line of 3 or 4 bites. Fleas often come from household pets, such as dogs and cats.


    Bedbugs can also bite

    The common bedbug has been the scourge of humanity for centuries, since at least the times of Ancient Greece, and reached plague proportions in the United States in the 1920s. The use of pesticides after the Second World War seemed to get the situation under control, but bedbugs have come back with a vengeance since the mid-1990s.


    Bedbugs feed at night (though they can go an entire year without eating) and stay hidden in cracks in the furniture, folds in the mattress, in picture frames and even wallpaper. They are attracted to our body heat and the CO2 we exhale.


    Their role as a vector of disease has been analysed, but no scientific evidence has been found to prove it. The sores caused by bedbugs are often arranged in a line and can have a spot of blood in the centre. Reactions involving blisters are rare.


    Treatment: prevention

    Although bites do not usually cause serious problems, it's best to try to avoid them, especially when visiting a country where cases of malaria or yellow fever have been reported (in which case, the bite itself is the least of your worries).


    Here are some tips:


    • You can prevent mosquito bites at night by closing the windows or using physical barriers such as mosquito nets.
    • People who are highly prone to bites should use insect repellent, and everybody on trips to tropical countries.
    • Ultrasound gadgets and similar devices have not proven to be effective.
    • Try to stay away from areas near untreated, stagnant water.
    • Do not wear cologne or use fragranced soap or lotion.
    • Wear clothing that covers the skin: long sleeves, long trousers and socks.
    • In summer months, when you might also wear a sunscreen, apply the sunblock first and then the insect repellent half an hour later.
    • If you have pets at home, check them for fleas and treat them if necessary.


    What to do when you've been bitten

    Sometimes you can't avoid it. But once you've been bitten and correctly diagnosed, there are some remedies that can help.


        • Apply a cold compress to the area to reduce the inflammation (for 10 minutes and repeat as necessary).
        • Topical application of ammonia-based compounds can be effective to relieve discomfort.
        • If the local reaction is very intense, you can apply a corticosteroid cream on the bite area and take an oral antihistamine to relieve itching (under medical supervision).