At 18 years of age, she was the youngest out of six contestants, and is only the second Papua New Guinean to be Miss Pacific Islands since MPIP PNG joined the Miss Pacific Islands Pageant franchise in 2011.
From a mixed parentage of Central and the Autonomous Region of Bougainville, Kariha has again created history by winning the Miss Pacific Island beauty contest.
Kariha also received Miss Tourism, Miss Personality, Best Topic Presentation/Interview and Best Talent awards, winning cash prizes as well as the crown.
Local media in Tonga reported that the 18-year-old was a crowd favourite.
The new Miss Pacific Islands has just completed her first year in a Bachelor of Arts Degree in PNG studies at the Divine Word University in Madang.
However, she plans to take next year off from studies to fulfill her role as Papua New Guinea and Pacific's cultural ambassador.
For the other placings in the pageant - first runner-up was Miss Cook Islands Lydia Simonis; second runner-up was Miss Samoa Sonia Piva; and the third runner-up was Miss Tuvalu, Emelipelesa Panapa.
Earlier in the pageant week, Papua New Guinea, through MPIP PNG Committee, made a bid to the Board of Miss Pacific Islands Pageant to stage the pageant in 2019.
The bid was successful and the host nation for 2019, Papua New Guinea, was announced before the crowning night.
Miss Pacific Islands Kariha and her MPIP PNG team will return home on Tuesday, December 3.
Meantime, Abigail Havora was the first Papua New Guinean to win the Miss Pacific Islands crown in 2015, in the Cook Islands.