A new strain of flu, described as "concerning", has triggered an early onset of cases this year, raising fears of a severe flu season ahead.
The potentially lethal H3N2 strain is believed to be driving the surge.
Flu cases have been reported a month earlier than usual this year, even before December has begun.
Already, the number of cases is three times higher than at the same point in 2024, reports Birmingham Live.
This could lead to hospitals being overwhelmed later this winter when the freezing weather truly sets in, especially if coronavirus cases also increase.
Health officials report that a staggering 84% of flu cases were identified as the H3N2 subtype where testing was available.
Doctors are now urging all those eligible for a free jab to come forward.
Sally Roberts, chief nursing officer and deputy chief executive officer for NHS Black Country Integrated Care Board (ICB), said: "We know that these viruses can cause serious illness, especially in people who are more vulnerable.
"Whether you're a member of the public, a patient, or a healthcare worker, I'd strongly encourage everyone who is eligible to come forward for their flu vaccination."
Paul Fisher, UKHSA West Midlands consultant in health protection leading on winter infections, emphasised: "With flu season hitting the UK early this year, it's vital that people at increased risk of severe illness and hospitalisation get protected as soon as possible.
"Every year, thousands of people are admitted to hospital after catching flu, and tragically, many also die.
"Many of these deaths could be prevented by eligible people having their flu vaccination - and it's best to get immunised as early as possible, as it takes the vaccine a few weeks to provide maximum protection.
"This early data provides reassuring evidence that this season's flu vaccine is providing important protection, despite concerns about the new subclade of the virus."