Impact of the COVID-19 Pandemic on Intestinal Parasitic Infection Positivity Rates Among Clinically Suspected Patients at a Tertiary Centre in Northern India: A Four-Year Retrospective Analysis
et al., Cureus, doi:10.7759/cureus.117132, Sep 2026
Ivermectin for COVID-19
4th treatment shown to reduce risk in
August 2020, now with p < 0.0000000001 from 106 studies, recognized in 24 countries.
No treatment is 100% effective.
Protocols combine treatments.
Retrospective 5,389 clinically suspected intestinal parasitic infection patients in India showing lower positivity rates during the period of COVID-19 ivermectin use.
Kamboj et al., 29 Sep 2026, retrospective, India, peer-reviewed, 8 authors, study period September 2021 - December 2021.
Contact: ypm.1702@yahoo.com.
Abstract:
Review began
07/27/2026
Review ended
09/27/2026
Published
09/29/2026
© Copyright
2026
Kamboj et al. This is an open access article distributed under the terms of the Creative Commons Attribution License CC-BY 4.0., which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
DOI: 10.7759/cureus.117132
Impact of the COVID-19 Pandemic on Intestinal Parasitic Infection Positivity Rates Among Clinically Suspected Patients at a Tertiary Centre in Northern India: A Four-Year Retrospective Analysis
Pratiksha Kamboj , Deepika Chakraborty , Yogendra P. Mathuria , Sandipta Charkraborty , Binal Mangroliya , Sindura Sudhakar , Tanisha Sharma , NIdhi Soni 1 2 3 4 3 3 3 3
1. Microbiology, Government Medical College, Haridwar, Haridwar, IND 2. Microbiology, Govind Ballabh Pant Hospital, New Delhi, IND 3. Microbiology, All India Institute of Medical Sciences, Rishikesh, Rishikesh, IND 4. Public Health, International Institute of Health Management Research, Delhi, IND
Corresponding author: Yogendra P. Mathuria, ypm.1702@yahoo.com
Abstract
Background: The COVID-19 pandemic changed healthcare-seeking behaviour and clinical priorities, potentially influencing the detection of intestinal parasitic infections (IPIs). Data evaluating these effects remain limited.
Objective: The primary objective was to assess changes in the laboratory positivity rate of intestinal parasitic infections (IPIs) among clinically suspected patients during the COVID-19 pandemic, including the period of empirical ivermectin use. The secondary objective was to compare IPI positivity rates across different age and gender groups over the study period.
Methodology: This was a retrospective laboratory-based observational study conducted at AIIMS Rishikesh from January 1, 2019, to December 31, 2022. Stool samples underwent macroscopic examination, saline and iodine wet-mount microscopy, and modified Ziehl-Neelsen staining for coccidian parasites. The timeline was divided into three policy-defined periods: pre-COVID (January 1 to December 31, 2019), early COVID19/ivermectin-included period (January 1, 2020, to August 31, 2021), and late COVID-19/post-ivermectin period (September 1, 2021-December 31, 2022). We applied a chi-square test and Bonferroni correction. Effect sizes are reported as prevalence ratios (PRs) with 95% confidence intervals (CIs).
Results: Of 5,389 samples, 97 (1.80%) were confirmed positive for IPIs; 103 parasites were isolated from 97 patients, with five patients harbouring co-infections. Overall positivity rates were highest in the age group of 41-50 years (3.00%; 13/433) and comparable between male (1.88%; 64/3,405) and female (1.66%; 33/1,984) patients. The pre-COVID positivity rate (2.78%; 37/1,330) exceeded that of the early COVID period (1.14%; 17/1,493; PR = 2.44, 95% CI: 1.38-4.32; p = 0.001). Protozoa predominated, with Giardia lamblia being the most frequent (44.66%; 46/103 parasites isolated). Following ivermectin withdrawal, positivity declined transiently (0.14%; 1/692; 95% CI: 0.03%-0.81%) before resurging (2.24%; 42/1,874).
Conclusion: Laboratory positivity for IPIs among patients with clinical suspicion fell during the initial COVID-19 period, most likely due to decreased healthcare-seeking and changes in referral patterns rather than a real shift in parasite prevalence at the community level. The observed temporal association with ivermectin use is only..
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