Parents whose babies died of whooping cough urge others: "Get the facts about immunisation."

Catherine and Greg Hughes know all to well the dangers of vaccination complacency and refusal.

When their son Riley died at four-weeks-old from whooping cough in 2015, he was too young to be immunised against the preventable disease and relied on protection from the community.

“I want all pregnant mums to know, it’s so important to have a booster when you are pregnant to protect not just you but your baby against whooping cough,” Catherine says.

"It’s so effective and to be able to give your baby the gift of immunity before your baby is even born is a miracle, it’s amazing."

While pregnant with Riley, Catherine didn't know she could ask for a booster as the scheme reccomending it had not yet been announced.

And that's why she and husband Greg have joined the federal government's new $5.5 million campaign to encourage parents to vaccinate their children - so that through awareness and education, other parents can be spared the same heartache.

A video of the pair telling Riley's story features alongside facts about vaccination programs and other resources on the website Get The Facts about Immunisation, launched on Sunday.

There, parents can find out why it's so important to immunise their children, as well as how to know if their child is up to date.

The website also features another heartbreaking story from parents David and Toni McCaffery, who lost their four-week-old daughter Dana to whooping cough in 2009. They lived in an area with low immunisation rates.

"We were just blissfully ignorant to, that there was a dangerous disease around us, for us we were just a family that bought home our third child and the joy that we had with her we just wanted to share that joy with other people," Toni says in the video.

"The importance of community immunity is that vaccination only works if we all do it, and we all do it on time.

"And what people need to understand is that to maintain your immunity you need to have regular boosters and that means babies, that means young children having their boosters on time, but it also means adults too."

Health Minister Greg Hunt says while more than 93 per cent of five-year-olds are fully vaccinated, immunisation rates in some parts of Australia remain low.

Listen: Sometimes, it's beneficial to structure our grief. (Post continues after audio.)

The "Get Facts about Immunisation" campaign, launched at Melbourne's Royal Children's Hospital on Sunday, will target parents in these areas through child care centres and social media, AAP reports.

Immunologist Ian Frazer says vaccinating a child protects not just them but the wider community.

"We still see cases of disease outbreaks, particularly in areas of low immunisation coverage, so it's important immunisation rates are as high as possible," he said in a statement.

"A parent will never know when their child may come into contact with someone who has got one of these infections."

For more information about the life-saving benefits of vaccination against preventable diseases and to hear the Hughes' and the McCafferys' full stories, visit  Get The Facts about Immunisation. You can learn more about Catherine and Greg Hughes' charity, Light For Riley, on Facebook.

-With AAP.