In contrast to molecular surveillance that maps the presence of bacterial pathogens in ticks, rodents, and wildlife, serological data provides a crucial look at how these pathogens move through domestic animal populations and into human hosts. Antibodies serve as fingerprints of past exposure—sometimes recent, sometimes historic—but always informative.
Prof. Sara Savić’s work focuses precisely on this immune imprint. Drawing from thousands of serum samples collected across farm animals, stray dogs, and occupationally exposed humans, her data paints a sobering picture of widespread but largely unrecognized circulation of zoonotic bacteria. If Petrović’s work warns us what’s coming, Savić’s findings reveal what’s already here.
Serology as a Mirror: Savić’s Insights into Circulation and Surveillance Gaps
If Petrović’s work maps the molecular landscape, Prof. Sara Savić focuses on its serological expression—what antibodies can tell us about exposure, circulation, and policy failure. Her presentation outlined a diagnostic blind spot around bacterial zoonoses in traveling animals, rural working dogs, and occupationally exposed humans.
Brucella canis
In a 2023–2025 cohort of 3,100 dogs screened for international movement, 11.2% tested seropositive. Of those:
- 30% presented with orchitis, back pain, or spinal lameness
- Only 5% had ever been tested previously
- 8 dogs had already been exported to Germany and Austria before diagnosis
She warned: “B. canis is not notifiable in many EU countries. But it’s zoonotic, underdiagnosed, and it travels with us.”
Brucella ovis
In collaboration with regional breeders, Savić’s lab tested 540 rams, with 7.1% seropositivity Farms with seropositive rams reported:
- Lambing losses up to 34% higher than regional baseline
- Breeding delays and increased culling
“These are not isolated numbers—they reflect systemic gaps in surveillance and communication,” she noted.
Q Fever in Humans and Livestock: An Overlooked Endemic Risk
Coxiella burnetii remains widely misunderstood and often undiagnosed. But in Serbia and neighboring countries, it is deeply endemic.
PCR positivity in abortion materials:
- 27.5% in goat placentas
- 22% in sheep
- 19.8% in cattle
Seroprevalence among:
- Veterinarians: 16.4%
- Animal husbandry workers: 21.1%
- Veterinary students (Bulgarian cohort): 5.9% PCR-positive, 21.6% seropositive
“Most of the infected students didn’t know they had Q fever. Their ‘flu’ passed, but the risk didn’t,” Savić warned.
Urban and Rural Surveillance of Leptospira Reservoirs
The zoonotic burden of leptospirosis is perpetuated by silent carriers, especially dogs and rodents.
1,840 dogs tested in 2023:
- 9.4% PCR-positive, mostly asymptomatic
- L. interrogans and L. kirschneri were dominant strains
- 42% of positives came from urban and peri-urban shelters
Water and soil sampling around affected farms:
- Leptospira DNA detected in 17.8% of water samples
- Up to 11.6% of surface soil samples positive in flood-prone regions
Structural Limitations in Zoonotic Disease Diagnostics
Despite growing awareness, diagnostics remain patchy. Only 12% of regional labs perform both serology and molecular tests. Turnaround time for confirmatory PCR in suspected abortions still averages 4–6 days. Access to certified Brucella and Coxiella reference strains for comparison remains limited.
“Science and technologies are not the problem—it’s the infrastructure and the political will,” Savić concluded.
PREPARE-TID aims to standardize diagnostic workflows, increase field-readiness through rapid extraction and mobile qPCR, and bridge the data-sharing gaps between animal and human health sectors.
Towards Integrated Surveillance: Where Veterinary and Clinical Worlds Converge
The microbial threats described by Savić and Petrović are real, underreported, and circulating now, not in some distant hypothetical future. From companion dogs to rural livestock, from rodent vectors to vet students, Serbia is a case study in the urgent need for faster, better-integrated diagnostics. The challenge is not whether we have the tools, but whether we use them in time. Southeastern Europe could become a model not of outbreak response, but of diagnostic foresight.
If the line between animals and humans is where outbreaks begin, then that’s exactly where our detection must start.
Take your diagnostics to the next level
- Request a SwiftX™ Virus trial kit – now available as CE-IVD – or protocol walkthrough (here)
- Watch the full Episode 2 of our PREPARE-TID webinar recording on YouTube (here)
- If you would like to collaborate with us, contact us (here)