HIV co-discoverer Robert Gallo talks about the Global Virus Network and the microbes competing for their attention.
The world is awash in microbes that threaten human and animal health. Unfamiliar viruses like Middle East Respiratory Syndrome (MERS) and Ebola are jumping to humans and other mammals at an increasing rate. Yellow fever and measles are resurging while the Zika virus is turning out to be more pathogenic than previously thought. Dengue fever and chikungunya virus, already endemic in significant portions of the developing world, are turning up in industrialized countries while HIV remains a stubborn global concern.
This is the landscape that preoccupies the Global Virus Network, an international coalition comprised of virologists from over 20 countries that was co-founded in 2011 by Robert Gallo, director and co-founder of the Institute of Human Virology (IHV) at the University of Maryland School of Medicine and the co-discoverer of HIV. The scientists who belong to the GVN are scattered around the globe at different universities, private research institutes and government laboratories, where they stand, ready and willing, to offer advice and insights on the viruses behind today's outbreaks and potential strategies to contain and prevent them.
For instance, last month it established a 24-member Zika Task force chaired by Scott Weaver, Director of the Institute for Human Infections and Immunity at the University of Texas Medical Branch in Galveston who has been studying Zika for eight years. The primary aim of the scientific task force is to help keep information flowing among the GVN colleagues researching and responding to the Zika outbreak gripping Central and South America, and the Caribbean. The GVN established similar task forces for the mosquito-borne chikungunya virus now evident in 45 countries, and the leukemia causing human T-lymphotropic virus (HTLV) that lacks both an effective treatment or a vaccine.
The GVN, which recently appointed José Esparza, the former Senior Advisor on Global Health (Vaccines) for the Bill & Melinda Gates Foundation as its president, doesn't consider itself a first responder, or a boots-on-the-ground kind of effort like the US Centers for Disease Control and Prevention Epidemic Intelligence Service. Its limited budget is used to educate the newest generation of virologists, provide small grants to scientists, advocate for research funding and disseminate accurate information to the public, policymakers, and businesses about viruses, vaccines, and epidemic preparedness. Its biggest challenge is establishing a strong enough funding base to support and expand its offerings.
So what sparked Gallo, who now chairs the GVN's Scientific Leadership Board, to form the virtual network with some of his fellow virologists? The idea was seeded during the early years of the AIDS pandemic and the scramble by scientists to try and nail down the cause of AIDS. Lots of theories were considered, including fungi and bacteria but it turned out to be neither. A year after French researchers identified a new retrovirus that they called lymphadenopathy-associated virus (LAV) in 1984, Gallo's team reported the isolation of a new retrovirus, but called it human T-lymphotropic virus (HTLV) type III. Both were later determined to be strains of HIV, which the Gallo team first linked as the cause of AIDS by obtaining many isolates and by their development of the serum antibody blood test for HIV in a series of five papers in the spring of 1984.
At the time, says Gallo, none of the working virologists had a global directive for researching the cause of AIDS during the earliest years of the epidemic; the World Health Organization did have a global mandate for fighting the new disease but had virtually no resident expertise in retroviruses. Similar disconnects existed, he said, during other greater epidemics of the 20th century, such as influenza and polio. Gallo thought this haphazard and counterproductive, and it got him thinking.
"When I would give lectures, people would often ask me what I thought we could be doing better to respond to emerging viruses like HIV," says Gallo. "It occurred to me that what we needed were expert scientists, virologists, medical virologists who were responsible, who were connected and who covered every last possible type of human virus."
Over time this idea gave way to the GVN, which represents 34 Centers of Excellence in more than 25 countries.
Eureka recently spoke with Dr. Gallo about the GVN, the growing number of diseases competing for the world's attention, and why networks like this are important. We also asked him about the recent development of novel Ebola and HIV vaccine candidates by Profectus Biosciences, a company spun out by IHV in 2005. Here are his edited responses.
Q: There are a lot of bugs circulating across the globe. Which ones should we focus on?
RG: Let's be truthful. It's really hard to know. I'll tell you one disease not terribly important on a global scale, but that some members of the GVN voted highly for in our list is HTLV. Why? Because it causes fatal disease in the 10% of people who become infected. And if you live in Iran, Brazil, Columbia, Peru, Japan or Indonesia, places where HTLV is a problem. Now, does it pose a threat to the US? No, because it's too hard to transmit. But in some parts of Brazil more people are infected with HTLV than HIV. They would probably rank this as really important. Ranking virus in terms of importance really comes down to what criteria you are using. Chikungunya virus and dengue fever are extremely high and spreading rapidly in southern India. But if run a cruise liner, norovirus is probably the most important virus there is. Lately, Zika is becoming worrisome because it's spreading so fast and associated with the autoimmune disorder Guillain-Barré and microcephaly.
Q: So what viruses top your list?
RG: Probably influenza because of the tremendous morbidity, the tremendous number of people infected every year and because you never know when the bird [strain} of influenza is going to hit. Influenza impacts the entire world. You can't escape from it, you can't avoid it. And if you get the wrong strain you have a good chance of dying from it. I would probably also include Ebola because of the ease of transmission.
Q: How might scientists who are part of GVN assist countries during an outbreak?
RG: Let's say, for instance, that you are the Minister of Health in Egypt and something new crops up. If you have contact with the GVN or a Middle Eastern virus center that belongs to the GVN, you can hook up with any other scientists in the GVN with the particular expertise in the kinds of problems that you are having.
Q: Are there particular diseases that scientists belong to GVN get asked about more than anything else?
RG: Not really. It goes in cycles. Last year, all the intensity and attention was around Ebola. Right now, Zika is getting a massive amount of attention and the men in the news lately include Massimo Palmarini, who is part of GVN, and heads the University of Glasgow's Centre for Virus Research, which focuses on zoonitic infections. Massimo has been quoted a lot about Zika because he works on it. In the U.S., it is perhaps Scott Weaver who heads the GVN Zika Task Force and is a real expert on these kinds of viruses.
Q: What do you think is driving up the incidence of Zika?
RG: I don't think we know. We don't fully understand its mode of transmission.
Q: On a different topic, an AIDS vaccine developed by your team at IHV started clinical testing last year. What makes this candidate unusual?
RG: It is designed to specifically induce the kinds of antibodies that bind to HIV's Envelope protein gp120 during a period of transition of the envelope protein that occurs when HIV via the envelope first attaches to the cell. Then, regions of the Envelope are exposed that are not normally exposed. These are highly conserved areas that the virus uses to enter [immune] cells so by binding to the gp120 protein during the transitional state, antibodies made against this transitional envelope prevent infection. The vaccine is safe, simple and easy to produce. The only problem is that the antibodies are not long-lasting, a problem we have with all vaccine strategies that target the envelope, and most of us believe the envelope must be targeted. So, we do still have significant scientific problems to solve.
(Photo credit: Institute of Human Virology)
How to cite:
McEnery, Regina. Viral Connections. Eureka blog. Mar 3, 2016. Available: https://eureka.criver.com/viral-connections/