Superflu grips countries like US and UK. Here's everything to know about the mutated flu strain

Hospitals across Pakistan have been reporting rise in influenza cases, driven by the H3N2 strain, following an earlier outbreak of H1N1. Children, elderly, and pregnant women are among the worst affected, with patients complaining of fever, cough, cold, body aches, and fatigue. Karachi is among one of the most affected cities by the flu.

This year, more cases have been reported that the previous years. The cases have largely been attributed to seasonal changes and about 40-50 new flu patients are reporting to hospitals in the Karachi city alone. In some cases the situation is aggravating to pneumonia, reported The Express Tribune.

Flu in the UK

Meanwhile, the NHS (National Health Service) - publicly funded healthcare systems in the UK- has reported its "worst-case scenario with flu cases jumping by 55% in a week. NHS England chief executive Jim Mackey said the situation could lead to 8,000 cases by the weekend, reported BBC.

However, the situation is "well within the boundaries" of what the NHS could cope with, according to Chris Streather, the medical director for the NHS in London.

Flu in the US

The new mutated flu strain version of the H3N2 virus has also spread in the US. Last week there was an 8% increase in people testing positive for the flu virus. An estimated 2.9 million people have fallen sick so far this season and about 1,200 people have died due to the virus, according to CDC, reported The Hill.

Colorado, New Jersey, New York, and Louisiana are amongst the worst affected due to the “high” transmission of the virus, according to the national data.

New variant of influenza called subclade K is behind most of the cases being reported this season. The subclade is a type of H3N2 influenza, which has in the past resulted in more hospitalisations and deaths.

Common signs of the flu

The common symptomps are, high fever that starts suddenly, intense body aches feeling extremely tired, dry cough, headache and sore throat. There could also be a loss of appetite and witness upset tummy

Steps to avoid the flu

Allow fresh air by keeping your windows in the room open, wash hands often and clean high-touch areas. Be mindful of covering your mouth when you cough or sneeze. Do wear a mask while stepping out.