Is there a causal nexus between norovirus infection and Guillain-Barré syndrome: The lessons learnt from GBS outbreak in Pune, India, 2025.

In January 2025, a significant outbreak of Guillain-Barré Syndrome (GBS) affected over 200 individuals in Southwest Pune. GBS, a rare neurological disorder triggered by infections, was linked in this case to antecedent illnesses, primarily acute diarrheal disease (ADD). Molecular screening for 19 pathogens revealed Campylobacter jejuni a known GBS trigger in nearly 50 % of cases, and norovirus in over 20 %. Contaminated drinking water emerged as the primary source of infection, with both pathogens also detected in poultry, suggesting a possible zoonotic link and highlighting the role of foodborne transmission. The outbreak was contained by March 2025 through urgent improvements to local water and sanitation systems. However, the event exposed critical public health shortcomings, including delayed diagnosis, limited access to specialized care, and weak disease surveillance. These factors contributed to the outbreak's severity and duration. Many patients required prolonged hospitalization and rehabilitation, placing a significant strain on healthcare resources and causing economic hardship for affected families. This outbreak underscores the need to recognize infection-associated GBS as a public health priority. It highlights the importance of cross-sector collaboration in clinical care, epidemiology, environmental health, and policy. Key actions include strengthening surveillance, ensuring safe water and food sources, improving clinical capacity for early GBS detection and management, and enhancing coordination between health systems. Addressing the infection-neurological disorder nexus is vital for effective prevention and timely response. This incident serves as both a warning and an opportunity to build more resilient public health infrastructure in rapidly urbanizing areas.