Abstract
Background:
Quality control programs are designed to provide a regular, objective, and independent assessment of a laboratory’s ability to provide an acceptable standard of service. For the diagnosis of Trypanosomosis and Paratuberculosis (Johne’s disease), microscopy is a simple and inexpensive technique that requires a standard or in-house diagnostic method and competent staff.

Aim:
This study aimed to evaluate laboratory performance on blood and fecal smear examination among public and private veterinary diagnostic laboratories in the United Arab Emirates (UAE) along with a questionnaire survey analysis from participant laboratories.

Methods:
Interlaboratory comparison programs were organized by the Biosecurity Affairs Division of the Abu Dhabi Agriculture and Food Safety Authority (ADAFSA). Each program was run by sending out fixed blood smears for detecting trypanosomosis and fixed fecal smears for detecting positive and negative types of paratuberculosis. A retrospective assessment of the data obtained for a period of five years (2019-2023) was conducted using Cohen’s kappa and percentage agreement of results. A questionnaire survey was also conducted among the participant laboratories to understand the needs and impact of ILC on quality control programs.

Results:
Data assessment demonstrated good performance in the identification of target pathogens, namely Trypanosoma spp. in blood smears and Mycobacterium avium subsp. paratuberculosis (MAP) acid fast bacilli in fecal smears. In addition, the staining method and quality of stains used by the different participating laboratories were also good. The overall percentage of agreement with Cohen’s kappa of 95% CI indicated substantial reliability in both ILC programs. Questionnaire analysis revealed a satisfactory report from the participating laboratories for the two ILC programs.

Conclusion:
The present study on the retrospective data assessment showed highly satisfactory performance results from the majority of participating laboratories and also has a good impact on improving the quality assurance and competence of participating laboratories in terms of trypanosomosis and paratuberculosis diagnosis. Among the participants, only three deviated results were found in this five-year period, and further investigation and improvement in performance were advised. Our study provides the first multiyear evaluation of veterinary microscopy-based ILCs in the UAE, addressing a regional gap in microscopy proficiency testing.
Keywords: Interlaboratory; Microscopy; Performance evaluation; Quality control.

Key words: Interlaboratory; Microscopy; Performance evaluation; Quality control.