David and Michelle Paul, who died in Fiji, told relatives that they had "vomited for 8 hours".

The Texan couple were planning a holiday in Fiji – relaxing on the palm-fringed beaches, perhaps snorkeling with manta rays or hiking in the Koroyanitu National Heritage Park.

Excursions like this one had become a tradition. The couple, who had previously published previous vacation photos of Cabo San Lucas and Hawaii, tried to travel together about once a year, said a family member at ABC's affiliate, WFAA. .

At the end of last month, David and Michelle Paul, of Fort Worth, boarded the family dog ​​and said what they thought was a temporary goodbye to their 2 year old son and daughter of David from a previous relationship. Then they took a plane for an adventure in the South Pacific, according to the station.

Shortly after arriving in Fiji on May 22, they are seriously ill. And despite medical treatment, their symptoms continued to worsen.

A Facebook user who appears to be David's mother wrote this week that the couple contracted the virus and died a few days later.

"David went to heaven," said the Facebook post. "We are so grateful that the Lord has provided eternal life through Jesus Christ, his Savior. David smiles in paradise, I'm sure of it. Her smiles and Michelle's would light in any room and I'm sure you who knew him knew it. . . I love you all. We are going to cry, but we are fine. "

[A mystery illness killed a boy in 1969. Years later, doctors believed they’d learned what it was: AIDS.]

A US State Department official confirmed the deaths of Michelle and David Paul in Fiji and offered his condolences to the couple's families.

But the circumstances surrounding their vacation and the mysterious illness that has turned their trip into a tragedy remain for the most part a mystery. Where did they go? What did they do?

And perhaps more importantly – what illness could the couple have been exposed to?

Very early, Michelle texted her parents, telling them that she and her husband had become ill.

"We are both going to the doctor now," the 35-year-old wrote in a series of text messages later obtained by ABC News. "We have been vomiting for 8 hours. Dave has diarrhea. My hands are numb. We will send a text message when we can.

After returning from the clinic, she wrote: "They gave us fluids and a nauseating drip. They gave us electrolyte packs and anti-nausea pills. "

"We still do not feel 100%," she added, according to ABC News. "Go and rest in our room."

Michelle passed away on May 25th.

Two days later, her 37-year-old husband was also dead, according to ABC News.

After their deaths, the Fiji Ministry of Health and Medical Services said in a seemingly unrelated statement that he was monitoring communicable diseases, including influenza.

Then on Thursday, after announcing that a couple on vacation in Fiji had fallen ill and had died, the ministry said in a statement that the flu had been "ruled out" and "that at this point we do not not think that there is a risk to the public ". the case is under investigation, he said.

The ministry said that a "small number" of health professionals who had close contact with the couple are under surveillance for the symptoms, but that they are "well."

The Ministry of Health and Medical Services said that he also worked with the US Embassy in the country, as well as with the US Centers for Disease Control and Prevention and Health. World Health Organization, to help determine the death of the couple. The WHO said it "gives access to laboratory services and other technical services in Australia".

Michelle's father, Marc Calanog, told People magazine that he and his wife are taking care of the couple's 2-year-old son, and that he is worried about the day when they will have to tell the toddler how his parents are. died. Calanog added that they were trying to hide their indescribable grief to the child.

"If we are depressed, it is my grandson who will suffer," he told the magazine. "Right now, we are taking care of my grandson. We want to be strong, because instead of being a grandparent, we could become a parent, which is a big change from what we have been doing for a few years. "

"Overall, we will recover," he added.

As for the couple's bitch, Tracey Calanog, Michelle's sister-in-law, told the WFAA that she had called many kennels near the couple's home in Fort Worth and that with the help of the community, she could have found the animal at home with her.

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