Forty out of every 1,000 patients visiting their family doctor are currently suffering from flu-like symptoms and this before the annual bout of influenza reaches its peak in Malta.

The colder weather and growing incidence of influenza in the rest of Europe could mean the number may go up, Health Promotion and Disease Surveillance director, Charmaine Gauci said.

People under 55 have been the worst affected this year. The annual sentinel surveillance exercise found that the number of influenza sufferers at this time is some eight times higher than last October.

According to news media Bloomberg, the flu virus hit Ireland and Portugal in mid-December and started progressing east across Europe. Ireland reported the worst flu season in 10 years midway through the influenza season, while last month Portuguese Health Minister Ana Jorge asked the military to provide additional beds for flu patients.

The influenza going round this year is a variant of the H3N2 strain, which had surfaced in Australia's Brisbane in 2007.

Angus Nicoll, influenza coordinator of the European Centre for Disease Prevention and Control in Stockholm, last month said this would be the first encounter with this variant for many Europeans. He said that while those who got jabbed against the flu would be protected, Europe's typically low inoculation rates would increase the amount of illness.

Dr Gauci, a public health specialist with a doctorate in epidemiology, said the influenza vaccine which was available this year was well-matched with the circulating strain.

"A well-matched vaccine protects between 70 and 90 per cent of under 65-year-olds who took the jab," she said, adding there was still a chance that those who got vaccinated would still fall ill with the flu.

Vaccine effectiveness drops to around 58 per cent in those aged over 65, but Dr Gauci, who described immunisation as "the cornerstone of public health", said it was still very effective in reducing deaths.

In fact, the vaccine prevents up to 70 per cent of hospital admissions and is up to 80 per cent effective in preventing flu deaths in the elderly.

She said it was not yet too late to take the flu jab - which takes around two weeks to become effective - since there have been years when the influenza season dragged on into March.

Eating foods high in vitamin C, keeping away from other sick people and washing hands rigorously can also help avoid the flu, she said.