New, more virulent Mpox strain poses significant risk to children, warn experts

The new and deadlier Mpox strain -- Clade 1b -- poses a notable risk to children, said experts on Thursday, amid an outbreak of the infectious disease in Africa.

The ongoing outbreak of Mpox which has been declared as a global health emergency by the World Health Organization (WHO) on 15 August, is different from what the world experienced earlier in the 2022 outbreak.

The 2022 outbreak was driven by Clade II, which is less virulent, and the infections were primarily seen in men who had sex with other men.

Since then, the WHO has reported 99,176 cases and 208 deaths due to Mpox from 116 countries.

India detected a total of 30 cases, with the last case in March 2024. The number of cases and deaths has increased significantly this year, with over 15,600 cases and 537 deaths reported so far in 2024.

The latest outbreak is majorly caused by Clade Ib which jumped to humans from animals in September 2023.

Dr Rajeev Jayadevan, co-chairman of the Indian Medical Association’s National Covid-19 Task Force, told IANS that the pattern of spread and mortality are markedly different from what we experienced in 2022.

This time “greater numbers of people are being infected, including women and children,” he said.

Traditionally, Mpox was transmitted through close physical contact or sexual contact -- as was observed in the 2022 outbreak -- and the infection was largely confined to the MSM (men having sex with men) community.

Historical data shows that while paediatric cases were rare in past outbreaks, the current resurgence has highlighted a growing vulnerability in this age group.

“Mpox is posing a notable risk to children, though they represent a smaller proportion of cases compared to adults,” Dr Rohit Garg, Consultant, Infectious Disease, Amrita Hospital, Faridabad, told IANS.

“Recent data indicates an increase in paediatric cases during the current resurgence, with children showing symptoms similar to those in adults but potentially facing more severe outcomes,” he added.

As per WHO data (2022-2024), as of July 2024, there were 1,156 (1.3 per cent) cases reported aged 0-17, out of which 333 (0.4 per cent) were aged 0-4. “Observed changes include higher transmission rates in households and schools, emphasising the need for vigilant monitoring and preventive measures,” Garg said.

This suggests that we need to keep an open mind about the possible modes of transmission, Jayadevan said, amid debate on whether transmission can occur through the air.

“The fact that children are readily getting infected suggests that either close contact or respiratory or both modes of transition could potentially be involved. This requires validation, however,” he said.