Leptospira interrogans serovar Hardjo (L. hardjo)

Leptospira interrogans serovar Hardjo (along with the genetically distinct but serologically indistinguishable Leptospira borgpetersenii serovar Hardjo) is a pathogenic spirochete and a primary cause of bovine leptospirosis worldwide [3, 7]. These bacteria are distinguished by their ability to establish long-term, often asymptomatic, colonization of the renal tubules and reproductive tracts in maintenance hosts such as cattle, which then shed the organisms in urine and genital fluids [5, 14, 15]. This chronic shedding facilitates environmental contamination and poses a significant zoonotic risk to humans, where infection can cause symptoms ranging from mild febrile illness to severe Weil's disease characterized by jaundice and renal failure [2, 11]. Therapeutic management involves broad-spectrum antibiotics like penicillins and tetracyclines, which target bacterial cell wall integrity and protein synthesis, respectively [8, 10]. In veterinary medicine, control is primarily achieved through vaccination with inactivated bacterins or recombinant proteins to prevent colonization and reduce the incidence of reproductive failure [6, 9, 16].

Other names

Leptospira borgpetersenii serovar HardjoHardjo-bovisHardjo-prajitnoL. interrogans serovar HardjoBovine leptospirosis agent

Antibiotics used against Leptospira hardjo function through distinct mechanisms: beta-lactams (e.g., Penicillin G) inhibit bacterial cell wall synthesis by binding to penicillin-binding proteins, while tetracyclines (e.g., Doxycycline) and aminoglycosides (e.g., Dihydrostreptomycin) inhibit protein translation by binding to the 30S ribosomal subunit [8, 10, 13].