Actor Zac Efron is back in good health after suffering an "extraordinary life-or-death medical emergency", and says he bounced back quick.

Efron, 32, was filming a documentary series called "Killing Zac Efron" in Papua New Guinea when he came down with a 'form of typhoid or similar bacterial infection' just before Christmas. He was flown to Brisbane, Australia, from Papua New Guinea on a 'life-or-death flight' with the assistance of medical professionals.

Efron on Sunday took to Instagram to let fans know he is feeling better, reports dailymail.co.uk.

"Very thankful to everyone who has reached out. I did get sick in Papua New Guinea but I bounced back quick and finished an amazing 3 weeks in P.N.G. I'm home for the holidays with my friends and family. Thanks for all the love and concern, see you in 2020," Efron posted.

He also shared an image with children from his time in Papua New Guinea.

It was reported after arriving in Brisbane, he was admitted in a private hospital in Spring Hill. At the hospital, he received treatment for several days, before being "given the all clear" by doctors to fly home to the US on Christmas Eve.

It is believed that the Hollywood actor flew to Papua New Guinea at the start of December to film the series, which will follow Efron as he will go deep into the jungle of a remote and dangerous island.