Giardiasis

Authors:

Minetti C, Chalmers RM, Beeching NJ, Probert C, Lamden

Unit Authors:

Abstract:

What you need to know

  • The number of patients detected with Giardia will increase as routine testing of stool samples using highly sensitive diagnostic tests becomes more widespread
  • Most patients with Giardia in the UK acquire their infection in the UK and not from overseas travel
  • Tinidazole and metronidazole are equally effective as first line treatments, although tinidazole has a simpler regimen and fewer side effects
  • Second line agents used in cases of treatment failure are unlicensed for giardiasis in the UK but are routinely used in many countries
  • Asymptomatic carriage of Giardia is common among household contacts, and testing of contacts is indicated in treatment failure and in household clusters

Giardia is a leading but treatable cause of infectious gastroenteritis worldwide, with a reported prevalence of 2-7% in high income countries and 2-30% in low income countries.1 Giardiasis is included in the World Health Organization Neglected Diseases Initiative owing to its burden and association with poverty.2 Its incidence in the United Kingdom is underestimated because of the lack of diagnostic sensitivity of traditional faecal microscopy3 and the mistaken belief that it is mostly acquired abroad, so often only people reporting foreign travel are tested. This update discusses the epidemiology, clinical presentation, diagnosis, and management of giardiasis specifically in high income countries.

References:

Journal:

BMJ

Research Themes:

Places