Smallpox

By | Updated June 3, 2015 5:00 PM UTC

Bearer of death, blindness and disfigurement, smallpox devastated humanity for at least 3,000 years. A global immunization campaign in the 1960s and 70s wiped out the disease, yet the variola virus that causes it lives on. It’s stored at two approved, secure laboratories: one at the Centers for Disease Control and Prevention in Atlanta, the other at Russia’s State Research Centre of Virology and Biotechnology, known as “Vector,” in Koltsovo, Siberia. Since smallpox was declared eradicated in 1980, there’s been controversy over if and when to destroy the lab specimens. Those favoring abolishing them want to rid the planet of an ancient menace that could kill again if the virus escaped — or worse, was used as a weapon dispersed through the air. Those against immediate destruction want time to study the virus’s deadly biological mechanisms, and to develop better treatments and vaccines. Now advances in genetic engineering are changing the smallpox debate.

The Situation

Six vials labeled “variola” were discovered in 2014 in an unsecured Food and Drug Administration cold-storage room on the Bethesda, Maryland, campus of the National Institutes of Health. The vials, probably from the 1950s, were found to contain variola DNA and destroyed. The finding raised the question: Could there be more smallpox samples out there somewhere? Also in 2014, the World Health Organization learned that variola DNA had been extracted from historical samples of human smallpox lesions on display at the National Museum in Prague. Smallpox’s potential as a biological warfare agent has been recognized for centuries, and methods for exploiting it took off during the Cold War. Some governments still think there’s a risk that secret variola specimens could be deliberately released. That threat has motivated the production and stockpiling of vaccines and the development of antiviral medicines.

The Background

As recently as 1966, smallpox was afflicting 10 million to 15 million people a year, and killing at least 1.5 million, in more than 50 countries. Almost two centuries after Edward Jenner began immunizing people with cowpox (a milder virus from the same pox family), smallpox was declared eradicated on May 8, 1980 — the first disease to be vanquished by mankind. Five years later, routine vaccination against smallpox stopped and governments began to discuss destroying the remaining stocks. As international consensus for the destruction built in the 1990s, new impediments to an agreement emerged: reports that Soviet researchers were developing biological weapons for use against the U.S. and U.K., and outbreaks in Africa of a related orthopoxvirus, human monkeypox. Both spurred renewed interest in variola research and increased opposition to scheduling the destruction of existing specimens. In 2002, scientists at the State University of New York at Stony Brook showed that they could engineer a virulent copy of the poliovirus in the lab, using mail-order fragments of DNA and publicly available genetic information. The research, financed by the Pentagon, set off a debate over whether other viruses could be fabricated the same way.

The Argument

Science moves rapidly after breakthroughs like gene mapping. In March, researchers in the Harvard University lab of geneticist George Church successfully inserted DNA from frozen prehistoric woolly mammoths into the genome of an Asian elephant — a few steps from realizing a scenario reminiscent of Steven Spielberg’s 1993 thriller “Jurassic Park.” Scientific advancements aren’t always positive. With the full genetic sequence of variola published and online, it’s at least theoretically possible for the virus to be synthetically engineered in small, private labs and unleashed on an unsuspecting, unprotected population. Even worse, an engineered strain might be tweaked to resist vaccines and medical treatments currently in development. This realization is now dominating the international smallpox debate, shifting the discussion away from when to destroy the last known viral vestiges to how to protect humanity once again from an ancient, deadly foe.

The Reference Shelf

  • The WHO aggregates information on smallpox, variola research and debate, and preparedness in the event of an outbreak. It also gives a detailed history of smallpox and its global spread.
  • The CDC looks at milestones in smallpox eradication.
  • Donald A. Henderson, who led global efforts to eradicate smallpox at the WHO from 1966 to 1977, outlined lessons learned to the Royal Society and dispelled myths about the virus in an interview with the Bulletin of the WHO.
  • Pathologist Stefan Riedel discusses smallpox in the context of biological warfare and Katherine Bourzac examines its potential as a bioterrorist tool.

First published June 3, 2015

To contact the writer of this QuickTake:
Jason Gale in Sydney at j.gale@bloomberg.net

To contact the editor responsible for this QuickTake:
Jonathan Landman at jlandman4@bloomberg.net