SYDNEY (Reuters) - Samoa on Thursday closed all non-essential public and private services for two days to combat a measles epidemic that has killed more than 60 people, mostly babies and children, in a battle complicated by a vocal anti-vaccination movement.

The measles virus has infected more than 4,200 in the South Pacific nation of just 200,000, government data shows, spurring medical teams to go door-to-door this week to vaccinate families still susceptible to the highly contagious disease.

The government urged unvaccinated families to hang a red cloth or flag outside homes as a signal for help, and imposed the shutdown to free up resources for its vaccine drive and keep even those fearful of vaccines home for the teams’ visits.

“Families are getting conflicting messages and it’s hard for them to then know what is the best thing for their child,” said Cate Heinrich, a Pacific spokeswoman at U.N. children’s agency UNICEF.

“It’s been a problem in Samoa but also globally with the anti-vaxxers,” she said, referring to groups that advocate against vaccines.

Measles cases are rising worldwide, even in wealthy nations such as Germany and the United States, as immunisation is shunned for philosophical or religious reasons, or even fears, debunked by doctors, that vaccines cause autism or other woes.

The virus took hold in Samoa last month after devastating communities in the Democratic Republic of the Congo, Madagascar and Ukraine, among others.

SOCIAL MEDIA

The devastating appearance of measles in Samoa has triggered conflicting advice on social media, especially on Facebook, which is a hugely popular platform in the Pacific.

Overseas networks originating in places such as North America have linked up with Samoans to send vitamins to the Pacific, say posts on social media, accompanied by claims that many cases may be caused by the vaccine.

Such assertions were absurd - and dangerous, said Dr Richard Kidd, an official of the Australian Medical Association.

“There are some people who can never be vaccinated because they might have allergies or they have serious immune problems and that’s why the rest of us need to share the responsibility to protect those who can’t,” Kidd added.

Vaccine rates in Samoa were just about 31% when measles took hold, the World Health Organization (WHO) says, a far lower proportion than in neighbours, such as Fiji and Tonga, where the disease has been more contained.

Kidd said a nation required a target coverage rate of 95% to reach “herd immunity”, or the ability to stop a disease from spreading.

In just over two weeks, the death toll has jumped more than tenfold to 62 on Thursday, the Samoan government said.

Samoan authorities have blamed low coverage rates in part to fears sparked by the deaths of two babies last year after vaccinations that put a temporary halt on immunisation efforts.

Although the deaths were found to have been caused by medications that were wrongly prepared, the tragedy prompted anti-vaccination groups to warn against immunisations in Samoa.

Online efforts by medical professionals to combat anti-vaccination groups include a chatbot named Mitara designed by two New Zealand doctors to answer questions about the disease on Facebook.

“If we are not putting our voices out there on social media, then suddenly peoples’ timelines and newsfeeds will be filled with masses of anti-vaxx content,” said Canaan Aumua, who designed the bot along with colleague Sanjeev Krishna.

“Samoans are our heaviest users at the moment.”