Spikes in cases of mumps and whooping cough have Northland's public health officials appealing to parents to be vigilant.
Eight confirmed cases of mumps have recently been reported in children from two schools in Dargaville.
With the school holidays approaching and Auckland in the grip of a mumps outbreak, health officials are calling for parents to keep their children up to date with immunisations. If in doubt, check the vaccination status through their GP or practice nurse.
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Northland had 10 mumps cases this year before the Dargaville cluster, but Auckland is grappling with its worst mumps epidemic in two decades. More than 450 cases have been registered there this year, that number surging in the last month.
Meanwhile, there have been 48 notifications of whooping cough in Northland so far this year, compared with nine cases in 2016 and 36 in 2015.
Twenty-five of the recent cases have been from Ngunguru, including a 1-year old infant who was hospitalised.
Whooping cough (pertussis) can be a very serious illness for babies and children, especially under 1, Northland Medical Officer of Health Dr Virginia McLaughlin said.
Whooping cough cases have risen across New Zealand with 938 probable, confirmed and suspected cases in the country for the year to September 15.
Mumps recently gained international attention with members of the All Blacks squad getting it, Dr McLaughlin said.
The team's rookie centre, 22-year old Jack Goodhue, from Kawakawa, left a week late for the Great Britain tour after picking up the illness in New Zealand. Teammates Luke Romano, Ardie Savea and Rieko Ioane have since succumbed to the illness. The players were probably infectious before they felt sick.
That clutch of high profile cases indicates how contagious the disease is and highlights the importance of vaccines being up to date for adults up to 29 years of age, Dr McLaughlin said.
"Vaccination is the best protection against mumps.
''If you or your children have not had the recommended two MMR [measles, mumps and rubella)] vaccinations, it is strongly recommended that you get these up to date.''
Mumps can cause swelling in the glands around the face and leads to meningitis in about one in 10 people. It is spread through the air or through contact with infected saliva.
Symptoms include pain in the jaw, fever, headache and swelling of the glands around the face. It usually takes between 12 and 25 days after catching mumps before the patient gets sick.