As the world continues to grapple with the impact and deaths left behind by the coronavirus pandemic, a new strain of swine flu with the possibility of mutating into a pandemic has come to the fore. A new strain of H1N1 flu has been detected in China, which must be "urgently" contained to prevent another pandemic, warn scientists.

The new strain of swine flu has been detected in China's pig farms. The H1N1 flu had wreaked havoc in 2009 leading to the deaths of over 2.8 lakh people. It eventually morphed into seasonal flu.

Called G4 EA H1N1, the new strain has been common since 2016. According to a study published by National Academy of Sciences, the strain effectively replicates in human airways. While it has only infected some people without causing any disease, there is a possibility of that scenario changing for the worse.

The study said that the G4 EA H1N1 has all the makings of a candidate pandemic virus. The researchers said that the spread in pigs must be urgently contained and humans monitored.

The researchers studied pigs across 10 provinces from 2011 to 2018. They collected 338 blood samples from workers across 15 pig farms as well as 230 from nearby households. They found the strain in 10.4 per cent of the workers and 4.4 per cent of the others. The infection was higher -- 20.5 per cent -- in workers between 18 and 35 years of age.

Ian H Brown, head of the virology department at Britain's Animal and Plant Health Agency said that predicting is not a precise science but close attention would be advisable. Brown warned that the virus could become as aggressive as the SARS virus.

Other variations of H1N1 was circulating in pigs in Europe and Asia for decades but the G4 virus began rising sharply after 2014.

US' top physician and immunologist said that virus was not an "imminent threat" but it is "something we need to keep our eye on the just the way we did with in 2009 with the emergence of the swine flu."