Samoa's health officials are awaiting international test results after an adult tested positive in Samoa for measles, which is thought to have been transmitted from the Auckland outbreak.
The Ministry of Health held a press conference in Apia late Wednesday and RNZ Pacific's correspondent, who attended the conference, said if lab results sent on to Melbourne are positive, for even one measles case, an outbreak would be declared.
Autagavaia Tipi Autagavaia said the suspected case related to an Aucklander who travelled to Samoa for a conference at the end of August, flew back to Auckland and was then diagnosed with the viral illness.
"Six people who were the contacts of that person were checked and followed up by the Ministry of Health here, and one out of those six are likely to be positive. But the sample from that person has been sent overseas for a test as well to reconfirm, to confirm, whether it's a measles case."
Samoa's Director General of Health, Takai Naseri, had also sent 38 samples from other suspected measles cases in Samoa to Australia for testing.
Twenty-five samples were sent last week and 13 this week - mostly from unwell children under-four who lived in Apia.
New Zealand has 1742 confirmed cases of measles notified this year so far and 1416 of those are in Auckland, where the worst outbreak in 20 years is most concentrated.
Australia was doing the lab confirmation as New Zealand was swamped.
"They're now sending it to Melbourne because...New Zealand cannot cope with any other testing because of the outbreak there right now."
No one in Samoa appeared to have been hospitalised yet with the virus.
Samoa's Health Ministry was also worried about measles transmission via RSE workers travelling between the two countries.
"They're also now considering seeking help of the World Health Organisation for some medicines to, for immunising our RSE workers in New Zealand.
"And those who are going to leave for RSE work in New Zealand, to make sure that you know, we have that protection of the country from any huge outbreak like the one in Auckland right now."
The World Health Organisation's (WHO) regional director for the Western Pacific, Takeshi Kasai, said it was important to remember measles was one of the world's most contagious infectious diseases and it could be deadly, especially for children.
But Dr Kasai said it was also an illness that was easily prevented by very safe and effective vaccines and the WHO was encouraging nations to provide current and clear information to parents about this.
"But very specifically to New Zealand, we have recently had the confirmed case in Samoa that linked up to the Air New Zealand [flight].
"We're really also encouraging people...in case you have contact, and a measles incident, to refrain as much as possible from travel. But again key is the immunisations," Dr Kasai said.
Even countries with high immunisation rates still had hotspot areas of low coverage that were hard to reach, Dr Kasai said, and there were plans to improve that over the next five years.
WHO recognised the antivaccination movement presented a serious risk to global health.
Dr Rabindra Abeyasinghe, acting WHO representative in the Philippines, said the 'anti-vax' movement, vaccine hesitancy and complacency had all emerged in countries that had not seen measles outbreaks for some time.
Adding to this, he said the Philippines had had problems with logistical challenges and access to vaccine stock, negatively impacting on children's compliance with the vaccine schedule and lowering herd immunity.
The Philippines saw an eight fold increase in measles cases from 2017 to 2018 with thousands of people infected and over 200 measles related deaths in the first seven weeks of 2019 and this may have triggered the Auckland outbreak.
Samoa's government was now looking at setting up isolation facilities for patients with measles, creating extra space in Apia for a children's pop-up vaccination clinic to speed up herd immunity, and extra air passenger surveillance, Autagavaia said.
"There's staff and also extra people working at the airport also being advised to look you know for passengers arriving with likely symptoms of fever, or rashes or anything like that."
The confirmation of even one case of measles in Apia would be a big deal for Samoa, he said, and the laboratory results were expected to be known by early next week.
'Really serious, horrible disease'
Meanwhile, Auckland Regional Public Health is optimistic that the outbreak is now waning with more vaccine stocks arriving and being distributed to medical centres.
There are three children from Counties Manukau District or South Auckland in hospital, and over the past three weeks the number of measles cases is decreasing.
John Cameron, an Auckland general practitioner and member of the metro-Auckland Incident Management Team, said the priority groups for vaccination were babies aged 12 months, four-year-olds and also the under 30's, who are not immunised or uncertain.
"Our practice nurses are sitting there armed with needles ready to jab anyone who fills those priority groups as soon as they possibly can.
"For people who think they may have measles, have the symptoms suggestive of, please contact your general practitioner team or health provider by phone before presenting at the practice, so that we can ensure that you are isolated from other people within the practice environment," Dr Cameron said.
Even though they were hopeful the worst of the measles epidemic had peaked, Dr Cameron said it was not a time to sit back and do nothing but rather a chance to figure out how to best protect people from measles, which he called a "really serious, horrible disease".