The HSE has said the current prevalence of both A and B flu viruses is "unusual", and that this had only happened three times in the last 20 years.
Dr Kevin Kelleher, the HSE's assistant national director for health protection, said "normally our seasons are predominated by the A virus, and the B virus comes along at the tail of the flu season, so this is unusual".
“It’s only happened two or three times at the most in the last 20 years that both two viruses have been prevalent equally at the same time. It doesn’t normally happen.”
While predictions of the “Aussie flu” – a H3N2 strain of influenza A– proved correct, the emergence of a separate influenza B virus in equivalent numbers was unexpected. Usually just one type, either influenza A or B, is responsible for the majority of cases.
Dr Kelleher confirmed the HSE purchased stocks of the trivalent flu jab following a recommendation by the World Health Organisation (WHO), which contains protection against three strains (two A strains and one B strain) of flu virus.
“The prediction made by the WHO for the vaccine didn’t include this strain. It included a not dissimilar strain but not this exact strain of B. That decision is all made a year or so in advance, and we order the vaccines and the vaccines go into production.”
Dr Kelleher said samples from GPs in the community showed the B virus was accounting for 60 per cent of flu cases, while in hospitals and intensive care units it was accounting for 50 per cent of cases.
He said the uptake of the flu vaccine had increased, but we “are not up to the targets we have set”.
Emergency departments
Meanwhile, the number of people on trolleys in emergency departments or on wards waiting for admission to a hospital bed increased to 575 on Tuesday, according to figures released by the Irish Nurses and Midwives Organisation.
The number of patients on trolleys reduced towards the end of last week after reaching a record high of 677 on January 2nd. However, many doctors and health administrators had anticipated that the numbers would increase again this week as the peak of the flu season approached.
Separately, on Tuesday the private hospital sector urged the Government to use its facilities to ease pressure on public hospitals during the current overcrowding crisis.
The Private Hospitals Association said: "Private hospitals have the capacity to deliver cutting-edge diagnostics, beds, personnel at consultant level to significantly reduce the number of patients on trolleys in a relatively short space of time.
"It's not surprising to see Minister [for Health] Simon Harris confirming the health service will need a further 2,000-2,500 beds over the next decade. However, for this to succeed it will take years to deliver the adequate infrastructure to meet Ireland's health needs."
