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Threatened pandemics and laboratory escapes: Self-fulfilling prophecies
This essay summarizes a more detailed review of the historical record with appropriate scientific references; it is available on the website of the Center for Arms Control and Non-Proliferation. The author thanks Lynn Klotz and Ed Sylvester for help with condensing the longer report for this article. Excerpts follow.
These narratives of escaped pathogens have common themes.
In 2010, 244 unintended releases of bioweapon candidate “select agents” were reported.
The swine flu scare of 1976 and the H1N1 human influenza pandemic of 1977. Human H1N1 influenza virus appeared with the 1918 global pandemic, and persisted, slowly accumulating small genetic changes, until 1957, when it appeared to go extinct after the H2N2 pandemic virus appeared. In 1976, H1N1 swine influenza virus struck Fort Dix, causing 13 hospitalizations and one death. The specter of a reprise of the deadly 1918 pandemic triggered an unprecedented effort to immunize all Americans. No swine H1N1 pandemic materialized, however, and complications of immunization truncated the program after 48 million immunizations, which eventually caused 25 deaths.
Human H1N1 virus reappeared in 1977, in the Soviet Union and China. Virologists, using serologic and early genetic tests soon began to suggest the cause of the reappearance was a laboratory escape of a 1949-1950 virus, and as genomic techniques advanced, it became clear that this was true. By 2010, researchers published it as fact: “The most famous case of a released laboratory strain is the re-emergent H1N1 influenza-A virus which was first observed in China in May of 1977 and in Russia shortly thereafter.” The virus may have escaped from a lab attempting to prepare an attenuated H1N1 vaccine in response to the US swine flu pandemic alert.
There has been virtually no public awareness of the 1977 H1N1 pandemic and its laboratory origins, despite the clear analogy to current concern about a potential H5N1 or H7N9 avian influenza pandemic and “gain of function” experiments. The consequences of escape of a highly lethal avian virus with enhanced transmissibility would almost certainly be much graver than the 1977 escape of a “seasonal,” possibly attenuated strain to a population with substantial existing immunity.
Eradication of natural smallpox transmission made the prospect of reintroduction of the virus intolerable. This risk was clearly demonstrated in the United Kingdom, where from 1963-1978 only four cases of smallpox (with no deaths) occurred that were imported by travelers from areas where smallpox was endemic, while during this same period at least 80 cases and three deaths resulted from three separate escapes from two different accredited smallpox laboratories.
From 1938 to 1972, the Venezuelan equine encephalitis vaccine caused most of the very outbreaks that it was called upon to prevent, a clear self-fulfilling prophecy.
Moreover, about five percent of SARS patients are “super-spreaders” who infect eight or more secondary cases. For instance, one patient spread SARS directly to 33 others (reflecting an infection rate of 45 percent) during a hospitalization, ultimately leading to the infection of 77 people, including three secondary super-spreaders. A super-spreader could turn even a single laboratory infection into a potential pandemic.
SARS has not re-emerged naturally, but there have been six escapes from virology labs: one each in Singapore and Taiwan, and four separate escapes at the same laboratory in Beijing.
Federal law bans Foot and Mouth Disease (FMD) virus from the continental United States, and it is held only at the US Department of Agriculture Plum Island facility off Long Island. Currently, however, its replacement, the National Bio and Agro-Defense Facility, is under construction in Manhattan, Kansas, under the aegis of the Department of Homeland Security. Moving FMD research to the agricultural heartland of the United States was opposed by many groups, including the Government Accountability Office, but Homeland Security decided on the Kansas location. In upgrading facilities to counter the threat of agro-bioterrorism, the department is increasing the risk to US agriculture of unintentional release.
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