Remote Primary Health Care Manuals

Worms ⚠️

Table 7.38 Common worms and sickness due to worms

Worm type Shape/aspect Can cause
Hookworm (Ancylostoma duodenale, Necator americanus)

Transparent worms 8-11mm long
  • Anaemia (weak blood)
  • Cough

Threadworm or pin worm (Enterobius vermicularis)

White thread-like worm 5-13mm long. Often seen in faeces
  • Itchy backside that wakes child at night

Whipworm (Trichuris trichiura)

Round worm 30–50mm long
  • Diarrhoea, abdominal pain, anaemia
  • Weight loss or growth faltering in child
  • Rectal prolapse if infection heavy — rare

Dwarf tapeworm (Hymenolepis nana)

 Tapeworm 25–40mm long. Lives in small intestine
  • Vague abdominal symptoms. Often no symptoms
  • Treat if child has abdominal pains, diarrhoea, growth faltering
  • Also check for other reasons for these problems

Strongyloides (Strongyloides stercoralis)

Up to 2mm long — can reproduce in body for many years, unless treated
  • Strongyloidiasis — often no symptoms but can cause
    • Smelly diarrhoea, abdominal pain, loss of appetite, constipation
    • Skin rash (especially one that moves along hour by hour), hives/urticaria (itchy sores) on lower back or buttocks
    • Cough, wheeze, haemoptysis (coughing up blood)
    • Low blood potassium especially in young child
  • Can rarely cause death due to
    • Severe secondary infection — blood infection, pneumonia, meningitis
    • Disseminated hyperinfection — massive worm infection spreads through body if person has weakened immune system, eg HTLV1 infection, using corticosteroids for more than 2 weeks, chemotherapy, transplant medicines

Testing for worms

Faeces testing

  • Keep specimens cool but not refrigerated — heat and cold will kill the worms
  • Send faeces specimen — as fresh as possible for
    • OCP (ova, cysts, parasites)
    • AND MC&S
    • AND strongyloides culture — only some laboratories do this

Testing for strongyloides — faeces and/or serology

  • Only test for strongyloides in the following situations
    • Person with symptoms that suggest strongyloidiasis
    • Person starting treatment that may weaken the immune system — test before starting treatment including person starting corticosteroids — if treatment for at least 2 weeks
    • Person with systemic infection from enteric (gut) bug and no other cause identified
  • Serology (blood test) — easiest way to test adults with symptoms which may be from chronic strongyloidiasis
    • Immunosuppressed people with disseminated strongyloidiasis may be serology negative 
  • Faeces test — usually best for children
    • Children with bowel symptoms are likely to have a new infection and may be serology negative 

Treatment

Hookworms, threadworms, whipworms, dwarf tapeworms

  • If positive faeces test — Table 7.39

  • Threadworms — also treat household contacts and carers to reduce risk of reinfection

Strongyloides treatment

  • If positive faeces test — Table 7.39 — ivermectin is preferred treatment
  • If positive serology — medical consult before treating
    • Blood test can be hard to interpret
    • Need to identify underlying or complicating factors
  • If person from high prevalence area (remote communities and some town camps) is on or starting treatment that weakens immune system — treat for strongyloides even if blood and/or faeces test negative
    • Treat before starting a treatment that weakens immune system AND every 3 months while on treatment
    • People with already weakened immune system may need 4 or more doses of ivermectin — medical consult

Table 7.39 Worm treatment if positive faeces or serology test  

Worm Medicine Dose Comments
Hookworm
Threadworm		 Albendazole* Oral single dose
  • 6–11 months — 200mg
  • 1 year and over — 400mg
  • Best with water on empty stomach
  • Tablets can be crushed or chewed
Threadworm or pin worm  Pyrantel Oral once a day for 3 days
  • 10mg/kg/dose up to 1g — doses

Repeat dose in 2 weeks
  • Use instead of albendazole for females who are or could be pregnant
Whipworm Albendazole* Oral once a day for 3 days
  • 6–11 months — 200mg
  • 1 year and over — 400mg
  • Best with water on empty stomach
  • Tablets can be crushed or chewed
Dwarf tapeworm Praziquantel Oral single dose

 If heavy infection — repeat in 7 days
  • Adults swallow whole
  • Children don’t like taste
Strongyloides Ivermectin**
(preferred treatment)		 Oral single dose
  • 5 years+/15kg+ — 200microgram/kg/dose — doses
Repeat in 1–2 weeks
  • For adults and children 5 years and over and 15 kg or more
  • Best with full cream milk or fatty food
Strongyloides Albendazole* Oral once a day for 3 days
  • 6–11 months and under 10kg — 200mg
  • 6–11 months and 10kg and over — 400mg
  • 1–4 years and under 15kg
    or pregnant (after 1st trimester) — 400mg

Repeat the 3 day doses in
1–2 weeks
  • For children 6 months to 4 years
  • Best with breastmilk (under 1 year), full cream milk or fatty food

* Albendazole — do not give to children under 6 months or females who are in first trimester of pregnancy (urine pregnancy test if not sure) without medical consult

** Ivermectin

  • Do not give to children under 5 years or less than 15kg or females who are pregnant (urine pregnancy test if not sure) without medical consult
  • People with weakened immune system may need 4 or more doses of ivermectin — medical consult

Follow-up — all worms

Follow-up all people who have been treated

  • If had strongyloides and from high prevalence area (remote communities and some town camps) AND on treatment that weakens immune system — treat with single dose ivermectin every 3 months
  • Everyone else — do faeces test again after 6 months if symptoms continue
    • If still positive — medical consult
  • Give iron supplements if needed — see  Anaemia in children, Anaemia in adults 

Prevention

  • Encourage personal and household hygiene
    • Keep nails short, wash daily, avoid scratching
    • Wash clothing, towels, bed clothes in hot water
  • Wear shoes to help stop worms entering through soles of feet

Asymptomatic eosinophilia 

Medical consult — may advise treatment after considering other common causes of eosinophilia such as atopy, allergy, scabies, medications

  • Only for those with eosinophils between 0.7 and 1.5 x109/L AND
    • Have no symptoms such as gastrointestinal upset or urticaria 
    • Not on a drug that may cause eosinophilia 
    • Not pregnant
  • Give
    • Albendazole dose as in Table 7.39 oral once a day for 3 days
    • AND Ivermectin dose as in Table 7.39 oral single dose. Important to take with full cream milk or fatty food

Community children’s de-worming program

Done in areas where hookworm is/has been common. Best done once a year just before or just after the wet season. Can be done with routine child or school-aged health checks

  • 6 months to 16 years — albendazole oral single dose once a year 
    • 6 months and over and under 10kg — 200mg
    • 6 months and over and 10kg or over — 400mg 
    • Best taken with water on an empty stomach
  • OR for girls who are pregnant (urine pregnancy test if not sure) — pyrantel oral — 10mg/kg/dose up to 1g — doses — single dose once a year