Re: 1976 The US Swine Influenza Immunization Program: A NYC Perspective
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3291401/
Dowdle , 2006
.
Suggested citation for this article: Dowdle WR. Influenza pandemic
periodicity, virus recycling, and the art of risk assessment. Emerg Infect
Dis [serial on the Internet]. 2006 Jan [date cited].
http://dx.doi.org/10.3201/eid1201.051013
In 1976, speculation was rife that a new pandemic strain was due
in a few years. The concept of 10- to 11-year influenza A virus
pandemic patterns, with disappearance of the predecessor virus,
seemed entrenched in the influenza literature. Previous influenza
pandemics had occurred in 1968, before that in 1957, and before
that in 1947; carrying the logic further, pandemics also occurred
in 1929, 1918, 1900, and 1890 (12). The concept was supported
by the World Health Organization (WHO) classification scheme,
which implied that 4 influenza A subtypes had occurred in humans
since 1933. In addition, seroarcheologic findings had been interpreted
as evidence that the swine virus had last appeared in 1918, the Hong
Kong virus (now designated H3) in 1900, and the Asian (H2) virus in
1890, not exactly 10–11 years apart, but in the same order (13,14).
To some, the next pandemic virus in the sequence was the swine
virus of 1918 (13).
On February 13, 1976, the New York Times published a guest editorial
to remind the public and policy makers that influenza pandemics
had marked the end of every decade—every 11 years—since the
1940s. The editorial urged accelerated pandemic planning and
coordinated vaccine research (15).
Risk Assessment in 1976.
Coincidentally, on February 14, 1976, the day after the Times editorial
was published, the Center for Disease Control (CDC) hosted an
emergency meeting with the US Army, Food and Drug Administration,
National Institutes of Health, and New Jersey State Health Department
to assess the isolation of swine influenza virus from the late January
outbreak at Fort Dix, New Jersey (16). Information was insufficient at
the time to assess whether the swine influenza virus outbreak was a
unique event in susceptible young recruits or the beginning of a
pandemic, but the isolation of a predicted potential pandemic strain
almost on schedule did not go unnoticed.
On March 10, the Army provided data to the US Advisory Committee
on Immunization Practices that confirmed person-to-person transmission
of swine influenza virus (17). The single swine influenza death loomed
large, although most cases were mild. No one at the advisory committee
meeting equated the disease potential of this virus with 1918, but the
association of swine influenza virus with the most devastating pandemic in
memory was widely speculated in the news media. Slightly more than a
month after the outbreak, no evidence suggested that a pandemic would
or would not occur; a situation such as the Fort Dix outbreak had never
been encountered. On March 18, the action memo from the Assistant
Secretary of Health to the Secretary, Department of Health, Education,
and Welfare stated that "severe epidemics, or pandemics, of influenza
occur at approximately 10-year intervals" and publicly linked swine flu
with the pandemic of 1918 (18).
When WHO convened a meeting of consultants in Geneva on April 7 (19),
3 months had passed without evidence of further swine virus transmission
anywhere in the world. The swine A/New Jersey strain had not replaced
the current A/Victoria strain, which continued to circulate at Fort Dix well
into February, and no evidence of swine/Victoria virus reassortants had
been seen. Theories of what might happen were being overtaken by the
realities of what was happening. The Fort Dix outbreak was beginning to
look like an isolated event.
A report from the United Kingdom on the behavior of swine influenza virus
in infected human volunteers would not appear in Nature for some weeks
(20), but in April early rumors circulated that swine A/New Jersey virus
was more infectious than classic swine virus but that the symptoms were
mild to moderate. The report added little to risk assessment; the findings
were consistent with events seen in the outbreak. But an accompanying
editorial in Nature summarized the UK and likely European view, which
urged caution in vaccine stockpiling and immunization programs and
continuing assessment, "until the shape of things to come can be seen
more clearly" (21).
Beginning in April and continuing into May, a group of US investigators
used the Delphi technique to obtain an expert risk assessment with
minimal bias (22). The 15 participating scientists and epidemiologists
concluded that if swine influenza virus were to circulate in the United
States, the epidemic would more likely resemble those of 1957 and 1968
than that of 1918. The probability of further swine influenza virus
outbreaks was estimated at 0.10.
On August 1, a series of news reports began to appear on a fatal
respiratory illness among American Legionnaires attending a convention
in Philadelphia (18,23). Wide but inappropriate speculation that the cause
of these unprecedented deaths might be swine influenza, accompanied by
equally unprecedented national publicity, precluded further opportunity for
rational risk assessment.
Theory of Predictable Pandemics.
Unknowingly, at the same time as the Fort Dix outbreak, the Working
Group on Pandemic Influenza met in Rougemont, Switzerland, on January
26–28. Issues addressed included the growing body of evidence linking
the origin of antigenic shift to animal reservoirs of influenza viruses (24),
the questionable validity of predictable patterns of pandemic periodicity,
and the appropriate classification of the 1947 strain (25).
----------------------------------------
15. Kilbourne ED Flu to the starboard! Man the harpoons! Fill 'em with
vaccine! Get the Captain! Hurry! The New York Times. 1976. Feb 13. p. 32.
16. Sencer DJ, Millar JD Reflections on the 1976 swine flu immunization
program. influenza in 1976. Emerg Infect Dis. 2006;12. doi:
10.3201/eid1201.051007. [PMC free article] [PubMed] [Cross Ref]
17. Gaydos JC, Top FH Jr, Hodder RA, Russell PK Swine influenza A
outbreak, Fort Dix, New Jersey, 1976. Emerg Infect Dis. 2006;12. doi:
10.3201/eid1201.050965. [PMC free article] [PubMed] [Cross Ref]
18. Neustadt RE, Fineberg HV The swine flu affair. Decision-making on a
slippery disease. Washington: US Department of Health Education and
Welfare; 1978.
19. World Health Organization Influenza. Wkly Epidemiol Rec.
1976;51:123.
20. Beare AS, Craig JW Virulence for man of a human influenza-A virus
antigenically similar to "classical" swine viruses. Lancet. 1976;2:4–5. doi:
10.1016/S0140-6736(76)92964-0. [PubMed] [Cross Ref]
21. Stuart-Harris C Swine influenza virus in man. Zoonosis or human
pandemic. Lancet. 1976;2:31–2. doi: 10.1016/S0140-6736(76)92980-9.
[PubMed] [Cross Ref]
22. Schoenbaum SC, McNeil BJ, Kavet J The swine-influenza decision. N
Engl J Med. 1976;295:759–65. doi: 10.1056/NEJM197609302951405.
[PubMed] [Cross Ref]
23. Fraser DW, Tsai TR, Orenstein W, Parkin WE, Beecham HJ, Sharrar
RG, et al. Legionnaires' disease: description of an epidemic of pneumonia.
N Engl J Med. 1977;297:1189–97. doi: 10.1056/NEJM197712012972201.
[PubMed] [Cross Ref]
24. Webster RG Strain surveillance in animals and birds. In: Selby P,
editor. Influenza: virus, vaccines, strategy. Proceedings of a working
group on pandemic influenza. Rougemont (Switzerland): Academic Press;
1976. p. 33–43.
25. Dowdle WR Influenza: epidemic patterns and antigenic variation. In:
Selby P, editor. Influenza: virus, vaccines, strategy. Proceedings of a
working group on pandemic influenza. Rougemont (Switzerland):
Academic Press; 1976. p. 17–21.
---------------------------------------------
for the serology review see also Dowdle's article from 1999
with more links:
http://www.who.int/bulletin/archives/77(10)820.pdf
-------------------------------------------------
see also the thread at panflu-stats
http://www.setbb.com/fluwiki2/viewtopic.php?p=2742&mforum=fluwiki2#2742
