Introduction: Salmonella is a bacterial pathogen responsible for both typhoidal (e.g., typhoid fever) and non-typhoidal infections. While non-typhoidal Salmonella typically causes self-limiting gastrointestinal illness, typhoidal Salmonella, particularly Salmonella typhi and Salmonella paratyphi, can enter the bloodstream, leading to invasive systemic disease. This is particularly dangerous in young children, where it contributes significantly to morbidity and mortality. In recent years, the misuse and overuse of antibiotics have led to the emergence of multi-drug-resistant (MDR) strains of Salmonella, making treatment more complex and less effective. In such cases, third-generation Cephalosporins, such as Ceftriaxone, are commonly used due to their broad-spectrum efficacy. This study focuses on the incidence, serotype distribution, seasonal trends, and antimicrobial resistance patterns of Salmonella, with an emphasis on Ceftriaxone resistance, based on data from Dr. Lal Path Labs, Delhi, over a four-year period (January 2021 to December 2024). Results and Discussion: A retrospective study conducted at Dr. Lal Path Labs between 2021 and 2024 analyzed 245,600 positive bacterial cultures from various clinical samples, identifying 6,332 cases (2.6%) as Salmonella species. The majority (99.1%) were isolated from blood, highlighting the invasive nature of typhoidal infections. Salmonella typhi accounted for 90.1% of cases, followed by other Salmonella spp. (4.9%), S. paratyphi A (3.8%), and S. paratyphi B (1.1%). A small number of isolates were also detected in abscesses, stool, and urine samples. Most cases occurred in males (58.9%) and in children aged <=12 years (49.1%). MDR strains were primarily seen in children under five, with no such cases reported in older age groups. Seasonal analysis revealed peaks in spring and summer, with a notable increase in 2024, suggesting environmental influences such as water quality and hand hygiene playing a role in transmission. Despite the growing issue of antimicrobial resistance, most isolates remained susceptible to key antibiotics: Ampicillin (93%), Cefixime (97.4%), Ceftriaxone (95.4%), Ertapenem (98.6%), Cotrimoxazole (97.5%), Azithromycin (98.8%), and Chloramphenicol (97.8%). However, resistance to fluoroquinolones was alarmingly high with 99.8% to Ciprofloxacin, emphasizing the need for antibiotic stewardship and susceptibility-guided therapy. Conclusion: This study highlights the ongoing public health burden of typhoid fever, particularly among children and during warmer months. The presence of multidrug-resistant Salmonella strains in young children further stresses the need for targeted preventive strategies. Effective management requires continued surveillance, responsible antibiotic use, and enhanced diagnostic capabilities to limit the spread of resistant infections and improve clinical outcomes.
Puneeta Singh (Mon,) studied this question.