Killer flu strain not predicted

Otumoetai Intermediate principal Henk Popping says a third of children at his school are away sick. File picture / Bay of Plenty Times

The flu strain which has killed three children in the past six weeks was not included in this year's vaccine batch because it was not considered a threat, the Health Ministry says.

Ministry spokesman Dr Pat Tuohy said apart from a small outbreak in 2002, New Zealand had not had large numbers of people infected with this type of influenza (Hong Kong B) since 1987.

This year's influenza vaccine provided protection against three strains of influenza, but did not protect against the influenza B Hong Kong strain, which has caused outbreaks in schools in Auckland, Wellington, Wairarapa and Christchurch.

However, it was included in last year's vaccine, giving immunity to many people who were vaccinated then.

Another strain of influenza B, Shanghai, is also circulating and is included in this year's vaccine.

Following the deaths of three children from influenza B complications in the North Island in the past six weeks, the ministry issued a warning yesterday that the virus was reaching epidemic levels.

Meanwhile, schools in the Wellington and Bay of Plenty regions have been hit hard by absenteeism among students and teachers struck down with flu.

More than 1000 Western Bay of Plenty children were home sick from school today. Up to a third of children at some schools are absent with general flu symptoms.

The sickness comes as Tauranga Hospital is treating its first confirmed case of the dangerous influenza B strain. A probable case is also being treated at Whakatane Hospital.

Otumoetai Intermediate principal Henk Popping said an average 10 students a class were away sick, mainly with flu symptoms. This amounted to a third of the school roll.

Mr Popping said recovery time was lengthy with some absent as long as a week.

Schools in Wellington, where the outbreak began around a month ago, said it coincided with the first meningococcal vaccine jab, which produces flu-like symptoms in some people.

Rongotai College principal Graeme Jarratt said absenteeism at his school was at its peak a month ago, around the time the first vaccinations began.

"We were hardest hit around a month ago, so we hope the worst is past, but we're not relaxing our vigilance.

"We've taken the ministry's warning on board about this pretty nasty bug and we have hygiene precautions in place."

The ministry is asking GPs and hospitals to report any children and young people with flu symptoms, and warning parents to keep a close watch on sick children.

"It now seems likely that around the world influenza B has been implicated in more deaths in children and young people than the records show," Dr Tuohy said

Meanwhile, a possible epidemic is also building in the South Island.

Nelson Marlborough infectious disease specialist Richard Everts estimates 7000 people in Marlborough will catch the flu this year, and 20 to 25 will be hospitalised with complications associated with influenza.

Marlborough schools have reported high rates of absenteeism this week, although it has not been established which strains of influenza, colds or viruses children have been suffering from.

Symptoms, which last 7-10 days, may include: a high fever, shivering, muscle pains, headache, dry cough, vomiting.

- nzpa, BAY OF PLENTY TIMES