A recent genetic study has linked the newer Mpox strain detected in Kerala to international travel, suggesting ongoing human-to-human transmission. The study, a first of its kind, focused on the Mpox Clade Ib variant, known for driving outbreaks in parts of Africa and its subsequent spread to other countries. Researchers from the ICMR-National Institute of Virology in Pune, along with teams from Viral Research and Diagnostic Laboratories across India, spearheaded the investigation, which examined ten lab-confirmed cases of Mpox Clade Ib in Kerala between September 2024 and March 2025.

The findings, published in the journal Virology, highlight the virus's active evolution, which has important implications for disease monitoring and public health preparedness. According to one of the researchers, the study confirmed that the Mpox virus is indeed mutating, as evidenced by a distinctive mutational pattern signaling sustained human-to-human transmission. Scientists observed a stronger mutation pattern in Clade Ib compared to older forms of the virus, indicating its continuous adaptation while circulating.

The study also revealed that the sequences contained mutations in several genes previously identified as hotspots in Clade Ib strains from the Democratic Republic of Congo, suggesting evolutionary convergence across different regions. Furthermore, a novel mutation was detected in six of the ten cases.

Researchers analyzed patients' symptoms, viral load, immune response, and the complete genetic sequences of the virus. The results indicated that the virus did not arrive in India through a single carrier but rather as part of a broader regional spread connected to international travel. Epidemiological analysis showed that nine of the ten patients had traveled abroad before testing positive for the strain, with local transmission noted in one case.

These findings underscore the importance of enhanced surveillance to monitor the spread of Mpox Clade Ib, which is prone to spreading faster and wider than older variants. In September 2024, Kerala reported cases of Mpox in individuals who had recently returned from the United Arab Emirates (UAE). Health officials directed those who had contact with the infected individuals to monitor for symptoms. Isolation wards were established in 14 hospitals across Kerala to manage potential cases.