Epidemiology and temporal trends of intestinal parasitic infections in Tizi-Ouzou, North-central Algeria: A 7-year retrospective hospital-based study

Abstract

Objective: To investigate the prevalence, species distribution, temporal trends, and associated demographic and clinical factors of intestinal parasitic infections (IPIs) among symptomatic patients attending a tertiary hospital in Tizi-Ouzou Province, North-central Algeria, over a seven-year period (2018–2024).

Methods: A retrospective analysis was conducted using laboratory records of 2568 stool examinations performed at the Parasitology-Mycology Laboratory of the Nedir Mohamed University Hospital Center. Parasitological diagnoses had been established using standard techniques, including direct wet mount, formol-ether concentration, and Scotch tape test. Prevalence rates were calculated, and associations with sex, age, hospital status, and hospital unit were evaluated using Chi-square or Fisher’s exact tests.

Results: The overall prevalence of IPIs was 28.4% (95% CI 26.7-30.2). Infection rates were higher in males (30.8%) than females (24.9%), in adults compared with children (30.8% vs. 21.9%), and in outpatients compared with inpatients (30.3% vs. 19.9%). Protozoa predominated (94.4%), with Blastocystis spp. as the most frequently detected parasite, increasing from 7.3% in 2018 to 22.2% in 2024. Dientamoeba fragilis also showed a rising trend (2.2% to 7.2%). Co-infections were observed in 5.3% of cases, mainly involving Blastocystis spp. A decline in prevalence was noted in 2020, likely related to COVID-19 hygiene measures.

Conclusions: IPIs remain highly prevalent among symptomatic patients in this region, with emerging protozoan species representing a growing public health concern. further prospective, multicenter studies incorporating molecular diagnostics and environmental investigations are essential to better understand the transmission dynamics of IPIs and validate these findings across diverse geographical regions and healthcare settings.

Keywords

Intestinal parasite / Prevalence / Protozoa / Algeria

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Ethical approval

This study was conducted using anonymized laboratory records, and no personal identifiers were accessed or collected. The study complied with institutional and national ethical standards for retrospective research. Ethical approval was obtained from the appropriate institutional review board of the Nedir Mohamed University Hospital Center (reference number 235/01/2020/DG). The requirement for informed consent was waived due to the retrospective nature of the study and the use of anonymized data, in accordance with the Declaration of Helsinki.

Data availability

Data will be made available on request.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Authors’ contributions

SY, OS and NAKT: editing, writing-original draft, visualization, data curation, conceptualization; IB and RB: data curation; ON, SS, NS: visualization, writing-review & editing, validation.

Publisher’s note

The Publisher of the Journal remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Edited by Pan Y, Lei Y, Zhang Q

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