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Published on: December 4, 2020
Prevalence of recurring symptoms after infection with Giardia lamblia in a non-endemic area
Knut-Arne Wensaas1, Nina Langeland, Guri Rortveit
1Section for General Practice, Department of Public Health and Primary Health Care, University of Bergen, Kalfarveien 31, Bergen, Norway. awensaas@online.no
Objective:
Investigation of the clinical course of infection with Giarda lamblia after a large outbreak in an area where Giardia is not endemic in humans.
Design:
A cohort of patients from primary healthcare with clinically defined giardiasis was investigated by retrospectively analysing data from the patients' medical records.
Setting:
Urban primary healthcare setting in Bergen, Norway.
Subjects:
From a population (n = 7100) assigned to two general practice clinics located in the outbreak area 134 patients met the inclusion criteria of at least one of the following: typical symptoms for at least one week, detection of Giarda lamblia in stool samples, or receiving a specific diagnosis. Of these, 119 gave consent to take part in the study.
Main Outcome Measures:
Proportion of patients with clinical giardiasis identified by detection of parasites in stool samples. Proportion of patients with prolonged disease and recurring symptoms.
Results:
A positive test for Giardia lamblia was found in 55% (66/119) of the patients. Specific treatment was given to 89 patients, and after treatment 36% (32/89) returned to their doctor because they experienced recurring symptoms. Compared with those not returning a significantly higher proportion of this group had seen their GP for other GI complaints in the previous two years.
Conclusion:
Laboratory-based diagnosis missed a substantial number of patients falling sick with giardiasis during the outbreak. One-third of the patients experienced recurring symptoms after treatment, and there was an association between previous gastrointestinal complaints and recurrence of symptoms.
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