No one in the immediate Kurian family had heard of human T-cell leukemia virus type 1 , HTLV-1, before patriarch George was diagnosed with blood cancer. Doctors told the family that his cancer was due to HTLV-1, which can cause leukemia and lymphoma in some patients.

"I started Googling. I knew nothing about it whatsoever," said Asha Kurian-Farris, George's daughter, who is based in California.

"It was amazing to me that it had been around, or at least people had known about it for 40 years at this point, but there's just not much outside knowledge of it," she said.

The first detection and isolation of HTLV-1 was in 1979, and the discovery was published in 1980. Decades later, in 2015, Kurian died of his cancer, which doctors believed was caused by the virus. Now, Kurian-Farris says she knows that her father -- a man from Kerala, India, with a big heart and a big love for science -- would want more awareness raised about the virus.

"He was just hoping that he could contribute knowledge to this larger puzzle," said Kurian-Farris, who is HTLV-1-negative and suspects that the virus was transmitted to her father from his mother. The virus can spread from mother to child, particularly through breastfeeding.

'I don't blame WHO at all. I blame us'

The virus also can spread between sexual partners, through unprotected sex; and by blood contact. Sometimes, it is referred to as a distant cousin of the human immunodeficiency virus type 1, HIV-1.

On Thursday, an abbreviated version of an open letter -- signed by 60 physicians, scientists and HTLV-1 advocates from around the world -- was published in the journal The Lancet , calling for the World Health Organization to implement five strategies to help prevent the spread of the debilitating and deadly virus.

The strategies include testing for HTLV-1 in sexual health clinics, testing for the virus in blood and organ donations worldwide, testing in routine prenatal care and advising against breastfeeding by infected mothers.

A public focus on HTLV-1 has come about in recent years as an extremely high prevalence rate, exceeding 40% , has been detected among adults in remote central Australia, with indigenous communities being the hardest hit, especially in the town of Alice Springs.

"We need WHO to make noise on this, to be aware of it, to make sure all health communities know about it, to push testing for it, et cetera, and we need (the US National Institutes of Health) and others to promote funding for it to make up for lost years of poor funding," said Dr. Robert Gallo, co-founder and director of the Institute of Human Virology at the University of Maryland School of Medicine, whose laboratory was the first to detect HTLV-1.

"I don't blame WHO at all. I blame us for not making enough assertion, with enough strength and enough potency, regarding the importance and the damage that this virus can do to an individual," said Gallo, who is also co-founder and scientific director of the Global Virus Network and co-chairman of the GVN HTLV-1 Task Force

"It's time to really correct that," he said.

A family comes face-to-face with HTLV-1

A first sign that Kurian was carrying the HTLV-1 virus emerged in the form of mouth sores, his family said. He visited a dentist and his doctor, but the sores came and went every few months.

JUST WATCHED Investigating the world's deadliest diseases Replay More Videos ... MUST WATCH Investigating the world's deadliest diseases 06:46

Kurian's doctors took a closer look. They noticed a high white blood cell count and continued medical testing. They found HTLV.

In the days after Kurian's diagnosis, his family searched for treatment options.

They applied for him to get a " compassionate use " exemption from the US Food and Drug Administration so he could be treated with a drug approved in Japan called mogamulizumab , which was found to target HTLV-1-infected cells. The FDA agreed, but the pharmaceutical company in Japan refused to release the drug, Kurian's family said.

Now, they hope his story illustrates the need for more research.

'They've been orphaned'

There is no cure and no vaccine for HTLV-1, but some scientists around the world are hoping to change that.

"Our research group has primarily focused on trying to better understand how HTLV-1 replicates, with the ultimate goal of trying to develop new therapeutic strategies to prevent virus spread and transmission -- and that's one of the open areas that's not been well-supported globally," said Louis Mansky, a professor and director of the Institute for Molecular Virology at the University of Minnesota, who was not involved in the new letter.

"The number of researchers is fewer than you would expect for such an important human infectious agent that causes cancer, as indicated in the open letter," he said. "The awareness of it and the support for research to better understand its prevalence, and for treatment of the viral disease, has lagged behind compared to some other viruses: HIV, hepatitis B virus, hepatitis C virus."

HTLV-1-infected patients often contact Mansky's lab, seeking new developments in treatment, and so he has seen their plight first-hand.

"Infected patients and loved ones feel as if they've been orphaned," he said. "So for those who are not infected or they do not know somebody who is infected, it may not have an impact on their lives, but when it's you or a loved one, it can make all the difference in the world."

Photos: 10 diseases you thought were gone Photos: 10 diseases you thought were gone There were 216,000 global cases of leprosy, an ancient and disfiguring disease, in 2013. Hide Caption 1 of 10 Photos: 10 diseases you thought were gone In the 19th century, scarlet fever was a common killer in Europe. In 2016, nearly 20,000 cases were reported in the United Kingdom -- the biggest increase in 50 years.



Scarlet fever is just one disease that many have forgotten but that is by no means gone, despite our best efforts to eliminate it. Hide Caption 2 of 10 Photos: 10 diseases you thought were gone

Though it's often thought of as a medieval disease, the World Health Organization reports 1,000 to 3,000 global cases of plague every year. The US averages seven new human cases a year, mostly in the Southwest . Pictured, a patient with gangrene and necrosis, caused by plague. Hide Caption 3 of 10 Photos: 10 diseases you thought were gone This 19-year-old girl in Neijiang, China, is being carried in a basket because she has rickets. Rickets is caused by a lack of vitamin D, which we get from sunlight. Experts believe rickets is making a comeback in developed countries because of the use of sunscreen and less time spent outdoors. Hide Caption 4 of 10 Photos: 10 diseases you thought were gone Gout was once known as the "disease of kings" because of its links to excessive food and alcohol consumption. These days, unhealthy lifestyles are behind an increase in gout in developed countries. Hide Caption 5 of 10 Photos: 10 diseases you thought were gone The deadly disease diphtheria affects the nose and throat. Vaccinations mean it is now rare in developed countries, but in 2011, nearly 5,000 cases were reported to the WHO, with many more probably unreported.

Hide Caption 6 of 10 Photos: 10 diseases you thought were gone Although there is a pertussis vaccine, there were an estimated 16 million global cases of whooping cough in 2008, killing about 195,000 children. Hide Caption 7 of 10 Photos: 10 diseases you thought were gone But globally, about In April 2015, the Americas became the first region to eliminate rubella; the Centers for Disease Control and Prevention says there are fewer than 10 cases each year.But globally, about 110,000 babies are born with congenital rubella syndrome every year. Hide Caption 8 of 10 Photos: 10 diseases you thought were gone TB, or tuberculosis, is one of the top 10 killers in the world, according to the WHO. In 2016, 10.4 million people around the globe contracted tuberculosis, and more than 1.7 million died. Ninety-five percent of those deaths were in developing countries Hide Caption 9 of 10 Photos: 10 diseases you thought were gone Vaccination programs mean polio is on the verge of extinction -- but there are still cases in Afghanistan and Pakistan. Hide Caption 10 of 10

Although the virus can be found throughout the world, there are certain endemic areas, such as the isolated cluster in central Australia.

The main highly endemic areas are the southwestern part of Japan; some parts of the Caribbean; areas in South America, including parts of Brazil, Peru, Colombia and French Guyana; some areas of intertropical Africa, such as south Gabon; some areas in the Middle East, such as the Mashhad region in Iran; a region in Romania; and a rare isolated cluster in Melanesia, according to the European Centre for Disease Prevention and Control

Elsewhere in the world, such as in the United States and the UK, prevalence remains low.

'I do believe it is possible to eradicate HTLV-1'

More research is needed to determine the true global prevalence of the virus, Gallo said, adding that he wonders about prevalence in other regions in the Middle East, Africa, Russia, China and South America.

"So, there are still unknowns. This has been a way under-studied and a way underfunded problem," he said, adding that there are several reasons why HTLV-1 has become a neglected virus.

"The major reason has been that it doesn't efficiently transmit. Even though its mechanism of transmission is very much the same as HIV, it's much less efficient," he said. "And it's maintained itself in certain populations," where not much medical attention has been provided.

Many regions around the world affected by HTLV-1 are poorer communities that often go overlooked by the medical establishment and don't have as many health care resources, Gallo said.

Follow CNN Health on Facebook and Twitter See the latest news and share your comments with CNN Health on Facebook and Twitter.

"I believe that now is a critical time to support continued research and application of that research to take us over the goal line in the fight against this deadly virus," said Susan Marriott, a professor in the Department of Molecular Virology and Microbiology at Baylor College of Medicine in Houston, who was not involved in the open letter.

With additional work, she believes, it is possible to eradicate HTLV-1 around the globe, but it will be difficult.

"First, the virus may not be detected until a patient shows signs of disease, which can be 40 or more years from the time that they were infected. During these 40-plus years, an infected person can unknowingly spread the virus to others," Marriott said.

"Second, some of the people who are most affected today live in remote parts of the world with minimal access to early detection options and state-of-the-art health care," she said. "I do believe it is possible to eradicate HTLV-1 from the world population, but it will be a challenging task."