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Publisher: Peytchinski Publishing Ltd.
ISSN: 1312-773X (Online)
Issue: 2026, vol. 32, issue3
Subject Area: Medicine
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DOI: 10.5272/jimab.2026323.6986
Published online: 22 July 2026
Original article
J of IMAB. 2026 Jul-Sep;32(3):6986-6990
EPIDEMIOLOGICAL CHARACTERISTICS OF PERTUSSIS IN PCR TESTED PATIENTS WITH SUSPECTED INFECTION
Milena Karcheva1
, Cvetan Popov2, Polya Marinovska3, Georgi Golemanov4, Nelly Doseva5, Maria Sredkova6,
1) Department of Infectious Diseases, Epidemiology, Parasitology and Tropical Medicine, Medical University - Pleven, Bulgaria.
2) Department of Anatomy, Cytology, Histology and Biology, Medical University - Pleven, Bulgaria
3) Department of Microbiology and Virology, Medical University - Pleven, Bulgaria.
4) Department of Chemistry and Biochemistry, Medical University - Pleven, Bulgaria.
5) Department of Biomedical Sciences, Medical University - Pleven, Bulgaria.
6) Virology Laboratory, Institute of Science and Research, Medical University - Pleven, Bulgaria.
ABSTRACT:
Purpose: To analyze epidemiological and clinical data of individuals tested for pertussis within the framework of routine disease surveillance
Material and Methods: We conducted a retrospective analysis of epidemiological and clinical characteristics in 109 patients tested for pertussis from five regions in Central and Northeastern Bulgaria. Nasopharyngeal samples were collected from all subjects. Bacterial DNA was extracted using the SaMag Bacterial DNA Extraction Kit (SM006, Sacace Biotechnologies, Italy) according to the manufacturer’s instructions. DNA amplification was performed using the Bordetella multiplex Real-TM PCR kit (Bordetella pertussis/B. parapertussis/B. bronchiseptica Real-TM, B84-100FRT, Sacace Biotechnologies, Italy), targeting the conserved region of the ptxA gene and species-specific genomic regions of Bordetella pertussis. Amplification and analysis were performed using the CFX96 qPCR system (Biorad, USA). All positive samples demonstrated amplification of the ptxA gene and specific genomic regions of B. pertussis.
Results: Between May and December 2024, a total of 109 nasopharyngeal samples from patients with suspected pertussis were tested at the Virology Laboratory of the Medical University – Pleven. PCR analysis confirmed pertussis infection in 25 cases (22.94%). The highest proportion of positive cases was observed among children aged <1 year (n = 12) and those aged 5–9 years (n = 4). Unimmunized individuals accounted for 12 (48%) of all laboratory-confirmed cases. According to epidemiological classification criteria, 16 cases (14.68%) were categorized as possible, 4 (3.67%) as probable, and 18 (16.51%) as confirmed.
Conclusion: Strengthening laboratory diagnostics, optimizing vaccination strategies, and conducting comprehensive epidemiological investigations are essential to enhance pertussis surveillance and control efforts.
Keywords: pertussis, surveillance, PCR test, epidemiology,
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Please cite this article as: Karcheva M, Popov C, Marinovska P, Golemanov G, Doseva N, Sredkova M. Epidemiological characteristics of Pertussis in pcr tested patients with suspected infection. J of IMAB. 2026 Jul-Sep;32(3):6986-6990. [Crossref - 10.5272/jimab.2026323.6986]
Correspondence to: Milena Karcheva, Department of Infectious Diseases, Epidemiology, Parasitology and Tropical Medicine, Medical University - Pleven; 1, Sv. Kliment Ohridski, Str., Pleven, Bulgaria. E-mail: doc.dr.karcheva@gmail.com
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Received: 09 January 2026
Published online: 22 July 2026