Infestations and Infections

creepy crawlies bugs and beasties

Infestations

Stings and Bites

OUTDOOR BUGS

      Midges Fleas Mosquitoes (females) Flies Wasps Tics       Bees Ants Moths and butterflies Centipedes Ladybirds Spiders

What do insect bites look like?

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Differential Diagnosis

Eczema / dermatitis Scabies Dermatitis herpetiformis Chickenpox or shingles Urticaria Delusions of parasitosis Papular drug eruption Polymorphous light eruption

Treating Insect Bites

 Bees – bicarbonate of soda    Wasps – vinegar Insects – oral antihistamines, topical hydrocortisone 1% cream, calamine lotion, aloe vera Tics – remove the tic after suffocating with toothpaste or vaseline, think of Lyme disease if a rash is present

Prevention is better than cure

 Mozzie net impregnated with permethrin  Deet – at least 50%   Lemon/citronella rubbed on exposed skin Clothing - avoid bright colours  Perfume - don’t wear any

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Diseases caused by insects

  Malaria (Anopheles mosquitoes) Lyme disease (tics) Tick borne encephalitis (tics) West Nile fever and Dengue fever (Aedes mosquito) Chikungunya fever (Aedes mosquito) Viral encephalitis (Culex mosquito) Filariasis (Culex mosquito) Tularemia (deer fly and black fly) Cat-scratch disease (cat fleas) Plague (fleas) Leishmaniasis and bartonellosis (sandflies, fleas and lice) Onchocerciasis (black fly) Trypanosomiasis (kissing bugs, tsetse fly)

INDOOR BUGS

 Scabies  Head lice   Pubic lice Body lice   Thread worms Fleas  Bed bugs

Sarcoptes scabiei

Itchy Itchy Itchy

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Scabies

The infestation mainly affects hands, wrists and genitals. Burrows are pinkish grey, 5-10 mm, most easily identified on the sides of the fingers, finger webs or under the wrist. Using magnification, the mites can be seen in the distal end of their burrows.

Symptoms may take up to 6 weeks to come out

Scabies in Adults

Within days to weeks a generalised itch and/or non-specific erythematous papular rash appears, sparing the head and neck. Later, papules may be found on the shaft of the penis and dermal nodules in the axillae and/or inguinal regions. Mites live up to 3 hours off the body

Scabies in Babies

is characterised by vesicles and pustules on the palms and soles which can persit after treatment. May have hundreds of burrows if too young to scratch.

Scabies treatment

     Treat everybody in the household and others with skin contact (remember split families) Permethrin 5% cream applied to the whole body below the hairline for 12 hours, repeat in 1 week. 60g cream for an adult, 30g for a child Malathion lotion left on for 24 hours Crotamiton cream (eurax) applied daily for 2 weeks Exclusion from school/work/nursery not necessary after first treatment

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Scabies treatment failure

Incomplete application of insecticide Premature removal of insecticide Inadequate penetration of insecticide through thickened skin or crusts Re-infestation by untreated contacts. Drug resistance All household contacts should be treated at the same time. It is wise to re-treat once a week for two or three weeks. Manage itch and eczematisation with emollients, topical steroids (or eurax) and oral antihistamines.

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Head Lice

Common, usually head to head contact, also live on brushes, toys or clothes for 3 days Moving brown or black specks like a sesame seed 3mm long Nits are the eggs left on the hair shaft Itchy Secondary infection from scratching Brush hair over a white cloth to see them, head inspection is unreliable Up to 60% of school children have them

Head lice treatment

 Combing wet or dry daily for 2 weeks   Malathion or permethrin scalp solution applied overnight and then washed out, choose aqueous preparations to avoid irritation, repeat 1-2 weeks One application 4% dimeticone gel  Repellents to minimise re-infestation  Hair care to prevent re-infestaion

Pubic lice

 Same kind of beastie as the head louse  Treat in the same way  Treat sexual partners and bed fellows together   Perform sti screen May also migrate to other body hair  Use vaseline on eye lashes

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Body Lice

Uncommon unless homeless or self neglect Look like head lice Live in bedding or clothes and lay eggs in the seams Clothes need to be boil washed, tumble dried or dry cleaned to get rid of lice Skin is very itchy and bites may be invisible under a layer of blood and crust Permethrin 5% cream can be used on the skin Treat eczematisation with emollients and infection with oral antibiotics or topical antiseptics

Thread Worms

    1cm long thin white threads seen on toilet paper, on pooh or at anus Female worms emerge at night and lay eggs around the anus and vulva which becomes itchy Spread by oro-faecal route Treat whole family together: if over 6/12 with single dose mebendazole 100mg chewable tablet and under 6/12 with piperazine repeated after 14 days

Fleas

       Live on the family pet Live on the neighbours and friends pets Live on soft furnishings and carpets Bite ankles mostly as they are closest to the floor Bite the body if the body is on the floor Bite the lap if stroking the pet on your knee Treat the furniture, carpet and the pet

Bedbugs (second hand furniture)

  Bedbugs feed on humans and live in furniture, sheets, clothes, suitcases, skirting boards They come out to feed at night and scuttle back into hiding afterwards Bites start as burning wheals with a central haemorrhagic dot These turn into firm papules, often in lines

Infections

Close bodily contact

Cellulitis

      Unilateral Painful Hot, red, sore, acute, spreading Patient unwell or feverish Treat with penicillin 500mg and flucloxacillin 500mg orally for at least a week Make sure it isn’t dermatitis or an insect bite

Impetigo

        Yellow scabs or crust Vesicles or blisters Red base Itchy, spreading Usually staph or strep Topical mupirocin, fucidin, or oral antibiotics Can spread like wild fire; nb hygiene and isolation, antiseptic washes can help Swab if very persistent and consider MRSA

Ringworm

 Topical fungal infection    Small red papules in an enlarging ring, healing from the centre out Topical clotrimoxazole, miconazole or nystatin Hydrocortisone cream will help you decide what it is!

Athletes foot

     Cheesy, wet, white skin, smells of sweaty socks, cracked or peeling skin Lateral toe webs between 4 th most common and 5 th toes Check the groin in men Topical clotrimoxazole, miconazole or terbinafine cream Secondary infection

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Thrush

White plaques that don’t move on a red background Can burn, itch and sting, sometimes very sore Classically cheesy white vaginal discharge Alters taste in mouth Treat with Miconazole gel, nystatin drops or pastilles, oral fluconazole Recurrent chronic condition for many needing repeated treatment.

Think of steroid inhalers and immunodeficiency

Herpes

 Cold sores can be anywhere on the body   Itchy and painful red spots which develop vesicles, often eroded Primary infection always the worst   Genital herpes may be cold sores Shingles and chicken pox can easily be mistaken for insect bites

Warts

      Anywhere on the body Run in families Last for years Lots of topical treatments but need to remove the dead skin first (freezing, salycilic acid 50%, hydrogen peroxide 1%, occlusion, acupuncture, efudix, imiquimod) Idea is to cause inflammation in skin so that the immune system finds the wart and then kills it OTC treatments safe and ok

Molluscum Contagiosum

       Pox virus on the skin Small pink papules with a belly button No symptoms unless they have become infected Can be massive and extensive in eczema or the immune compromised No treatment normally needed Last for months, contagious, no isolation required New otc product available molludab 5% potassium hydrochloride