A swine flu outbreak across Wairarapa is knocking out students before lunchtime and stretching relief teachers to breaking point.
Wairarapa is leading the Wellington region with nearly half of students at some schools staying home because of fever, chills, headaches, sneezing and in some cases diarrhoea and vomiting.
Swabs taken from children's throats earlier this week have returned positive for H1N1, said Annette Neesdale, Medical Officer of Health.
H1N1 was the predominant strain of flu in New Zealand this winter, so this result was not a surprise, Dr Neesdale said.
''While these are the first confirmed cases in the Wairarapa this winter it's highly likely that other influenza-type illnesses are also this strain.'' Dr Neesdale also said that now the prevalent strain had been confirmed, in most instances swabbing was no longer required, except in the hospital setting if patients had developed complications.
Lorraine Southey, acting principal for St Theresa Primary in Featherston, said 63 out of 133 students were absent.
''We have never had numbers like this before _ this is really bad. Speaking to the principal yesterday, she said she has known numbers as high as 50 per cent.''
Neil Preston, acting principal of Greytown Primary, said at the start of the week the school made six calls to parents to pick up children from the sick bay.
''We are pretty astute at knowing whether kids are faking it. We have been losing some during the day. This is genuinely not a put-on, this is genuinely kids getting sick quite suddenly, they just fade as the day goes on,'' he said.
His staff were also being wiped out, with four classroom teachers and an office staff member off on Monday.
Sue Walters, principal of Masterton Primary School, said this was the first time in her 19 years as a principal that she had been instructed by health authorities to clean all light switches, door handles and telephones.
''What they don't take into consideration, quite honestly, is this is a school. So are we going to disinfect all the pencils, scissors, glue sticks, paint brushes and pieces of paper every day before the children come in?''
The H1N1 outbreak was first notified to Public Health on Friday, and the team quickly swung into action. Information on influenza has been sent to all schools across the district to send home to parents. Parents are being advised to keep children home until they have been symptom free for 48 hours. The illness does not always cause coughs and sneezes. Some children experience stomach upsets with nausea, diarrhoea and vomiting. Information is now being sent to aged residential care facilities, though older people appear slightly less at risk than usual because the current strain is similar to the outbreak in 1957. ''Vaccination still provides the best protection and is very important for people who have other medical conditions,'' said Dr Neesdale. ''Immunity is not established for 10-14 days, though, so it's possible to still get the flu during that time.'' Masterton Medical has reported more than 60 cases a day for the past three days of influenza-type illnesses.