A mother has shared a heartbreaking video of her 18-month-old son suffering from whooping cough.
The video shows the little boy coughing and crying as he sits whimpering in his distraught father's arms.
US mum Jessica Leigh Boren says her son contracted whooping cough after she stopped vaccinating him, and posted the video as a warning to other parents not to make the same mistake.
"This is guilt. Guilt of putting not only my son at risk, but my community too," she says in her now-viral Facebook post. "This is why you SHOULD vaccinate and protect your children.
"This is a mother that see's 'anti-vaxx' all over social media and becomes terrified. Unsure whether to give or not give vaccines (even though she did for both of her girls).
"Terrified to 'pump her baby with poison'. Worried she's harming her child. So she stops vaccinating after 6 months. (ETA: I tried "spacing them out" so he did not get all 3 shots.)
"This is a baby boy struggling to breathe and turning blue with every cough. Coughing for over a minute each time. Multiple times an hour. For 5 days. Getting worse by the second.
"This is my happiest child, unable to laugh without having a coughing spell."
Whooping cough, also known as pertussis, is a highly contagious bacterial infection of the lungs and airways.
Commonly known as the "100 day cough", it is most serious in babies under the age of 12 months.
Boren's post has been shared more than 84,000 times and her videos have more than five million views.
The mother of three explained her message is not an attempt to "bash the anti-vaxx community" or place any blame on anyone, but purely to tell her story and warn other parents of her horrible experience.
Back home in New Zealand, Tauranga is currently caught in the grip of a whooping cough outbreak which has already doubled last year's numbers.
And health authorities are warning parents to immunise their babies from the potentially fatal disease.
In 2017, Tauranga recorded a total of 75 cases of whooping cough. This year to date, there have been 155 cases.
Toi Te Ora Public Health Organisation chief medical officer Dr Phil Shoemack said it affected babies the most and in extreme cases, they could die.
''Babies can struggle to breathe, and it's very distressing particularly in the under 1-year-olds. Often they are admitted to hospital as it affects their ability to breath because they have smaller lung capacity.''
''It can be life-threatening ... and there have been documented instances where children under the age of 1 have died.''
New Zealand data from the immunisation schedule revealed only 85 to 90 per cent of children were vaccinated against whooping cough, which required three shots at different ages from 6 weeks to 5 months and one before they started school.
Dr Shoemack said more parents needed to immunise their babies.
Antibiotics could be administered but were used mainly to stop the person infecting others, he said.
A vaccine and booster shots were also available for adults, older people and pregnant women, which Shoemack said was advisable as immunity was not lifelong.