The JN.1 subvariant of the Covid virus has been detected in Thane, which is close to Mumbai. The subvariant is mild but highly transmissible, and most detections are accidental or among pre-surgery Covid test patients. Mumbai faced multiple outbreaks of measles, influenza, dengue, and other viruses in 2023. The slackening of Covid surveillance and the lack of positive samples hindered genomic testing in Mumbai. Scientists predict that Covid surges will continue to occur periodically.