Anti-immunisation group The Australian Vaccination Network has been forced to insert the word "skeptics" in its name to better reflect its position.
The group's new name, Australian Vaccination-Skeptics Network (AVSN), came into effect last week following an order by the Administrative Decisions Tribunal.
The group says it was forced to use the American spelling of sceptics after "hate groups" prevented it registering its pre-approved name, Australian Vaccination Sceptics Network.
It also criticised the state government for taking it to the tribunal.
AVSN's public officer Meryl Dorey said the name change will have "no effect whatsoever" and was a waste of government money.
"I don't think anyone was confused about what our organisation stood for," she told AAP on Monday.
"I think it says more about the government to try and get us to close down."
NSW chief health officer Dr Kerry Chant said it was important the group's name be changed so that there would be no doubts about what it represents.
"We really don't want that misinformation to sway people's decisions on such important issues," she said.
Dr Chant said despite strong support for immunisation in Australia, health agencies needed to avoid complacency in getting the message out about the importance of vaccination.
She pointed to a recent spike in cases of measles, particularly in travellers returning from the Philippines.
"It's also very important we have high levels of measles coverage so we can protect young babies in particular," Dr Chant said.
Dr Vicky Sheppeard, Director Communicable Diseases NSW Health, said health experts wondered why the media often gave equal airtime to anti-vaccine groups, such as the AVSN, on such important matters.
The AVSN certainly should be able to have their voice heard but shouldn't be given equal time by the media, she said.