The other two recent cases were linked to a young woman in her 20s who had returned to New Zealand after travelling overseas and had infected two other family members living in the same Tauranga household, he said.
"These two patients have been asked to remain in isolation in their own home until the risk of passing on this illness to other people has passed," Shoemack said.
"Measles is a very infectious viral illness that spreads easily from person to person."
Shoemack said measles could be a serious illness with about one in 10 people needing hospital treatment, which was the case for one of the 10 confirmed Western Bay cases.
Toi Te Ora was not investigating any further reported cases and he hoped these two separate outbreaks meant measles would not spread to others in the community.
He urged anyone travelling overseas to not just think about getting vaccinated against contracting exotic diseases such as typhoid and cholera but also measles and influenza.
Immunisation was "very effective" in preventing measles and the vaccine that protects against measles is the MMR (measles, mumps and rubella) vaccine.
"It's important that parents ensure that their children receive their free routine MMR immunisations on time at 15 months and 4 years of age.
"If for any reason you have never had a dose of MMR vaccine now is the time to get one. After just one dose of MMR vaccine about 95 per cent of people will be protected from measles, and 99 per cent of people who have had both MMR doses will be protected from measles."
People born before January 1, 1969 are considered to be immune because measles used to be common, and so this age group did not need the measles immunisations.
The Ministry of Health recently highlighted that since 2012, all cases of measles in New Zealand came from travellers bringing the disease from overseas and that there are currently significant measles outbreaks in many countries.
If you think you have measles, call ahead for advice
"If you think you or someone in your family may have measles, stay at home and phone your doctor to alert them of your symptoms and allow them to make arrangements to assess you safely and without infecting other people, or call Healthline on 0800 611 116 for advice," Dr Neil de Wet said.
Measles facts
Measles is a highly infectious viral illness and is spread from person to person through the air by breathing, sneezing or coughing. Just being in the same room as someone with measles can lead to infection if you are not immune. Measles can be serious with around one in 10 people who get measles needing to be hospitalised.
The first early symptoms of measles are fever, runny nose, sore red eyes and cough.
After three to five days a red, blotchy rash appears on the face and head and then spreads down the body.
For more information:
· Toi Te Ora Public Health website: www.toiteora.govt.nz/measles
· Immunisation Advisory Centre free phone: 0800 IMMUNE (0800 466 863)
· Immunisation Advisory Centre website: www.immune.org.nz
· Ministry of Health 2019 measles outbreak information