Re: why would I be given an adenovirus and swine flu injection?

Dear Mark:

Thank you for your question!  It raises an interesting point about the 
risks versus the benefits of immunization.  When the government recommends 
immunization, it must weigh the possible risks of the immunization, such 
as causing the disease that is being immunized against or another 
unexpected complication, against the benefits of the vaccine, namely 
preventing widespread disease.

The two vaccines you were given in 1976 are very different from one 
another.  The first one, the swine flu vaccine, was only administered 
during 1976 (1,2).  It was meant to prevent a pandemic of influenza after 
an outbreak of swine flu at Fort Dix, NJ.  During a flu outbreak, many 
individuals become sick and may even die due to complications of the viral 
infection.  People housed in crowded conditions and under stress, which 
would certainly include military trainees undergoing basic training, are 
especially at risk for becoming ill.  The swine flu vaccine was 
discontinued in 1976, the same year it was started, due to associations 
with Guillain-Barre Syndrome (1,2).

Guillain-Barre syndrome occurs about 1-3 weeks post viral infection or 
immunization.  It is idiopathic, meaning we don't understand why it 
happens, and is characterized by symmetric pain and weakness of the 
extremities, which may in extreme cases lead to paralysis.  This paralysis 
can extend up to involve the thoracic muscles, arms and face.  The pain 
and paralysis follows a variable course, but usually resolves completely 
within a few weeks or months (3).

The other vaccine you were given, against adenovirus types 4 and 7, is 
still in use today, although vaccine stocks are currently critically 
depleted.  Adenovirus, which is a different virus from influenza viruses 
and thus needs its own vaccine, again is a threat to people housed in 
crowded conditions under stress.  This virus is associated with ARDS, or 
adult/acute respiratory distress syndrome, which can be fatal.  ARDS 
results in increased permeability of the capillaries in the lungs, leading 
to fluid accumulation in the lungs.  Fluid in the lungs prevents effective 
oxygenation of the blood.  There is also a huge influx of immune system 
cells, which are trying to kill off the virus, but end up contributing to 
the fluid in the lungs and poor oxygenation of the blood.  The main 
treatment for ARDS is to help with blood oxygenation and help the body 
clear the inciting agent, in this case the virus.  ARDS is a very serious 
condition, and death rates as high as 50% have been reported (4,5).  The 
adenovirus 4+7 vaccine prevents this serious complication.

There are no known complications to the adenovirus vaccine.  The only 
drawback I can think of is that adenovirus is currently the vector of 
choice for people working on gene therapy treatments.  For gene therapy, 
you need a method to get the gene inside the cells you care about.  
Viruses have been perfecting methods to get inside cells for millenia, so 
researchers borrow the virus' expertise by having it shuttle a desired 
gene into the cells, rather than the virus' own disease-causing genes.  
Having been vaccinated against the adenovirus vector, you would probably 
make a poor candidate for this method of gene therapy, should the need 
arise.  Gene therapy, however, is likely still many years from being 
brought to the clinic, so your adenovirus vaccine was probably not a 
detriment.

I hope I have answered your question, and if you have any more, please 
don't hesitate to contact us!

Ingrid Dodge
ingrid_dodge@student.hms.harvard.edu

References:
1.  Dowdle, WR. "Pandemic influenza:  confronting a re-emergent threat."  
Journal of Infectious Diseases, vol. 176, supplement 1: S69-72, 1997 Aug.

2.  Hilleman, MR.  "Cooperation Between Government and Industry in 
Combating a Perceived Emerging Pandemic:  The 1976 Swine Influenza 
Vaccination Program."  Journal of the American Medical Association, vol 
275 (3):241-243, 17 Jan 1996.

3.  Fauci et al, Ed. Harrison's Principles of Internal Medicine, 14th 
Edition.  New York: McGraw-Hill, 1998.

4.  Weinberger, SE.  Principles of Pulmonary Medicine, 2nd Edition.  
Philadelphia:  W.B. Saunders Co., 1992.

5.  Barraza, EM; Ludwig, SL; Gaydos, JC; Brundage, JF.  "Reemergence of 
Adenovirus Type 4 Acute Respiratory Disease in Military Trainees:  Report 
of an Outbreak During a Lapse in Vaccination."  Journal of Infectious 
Diseases, 179 (6): 1531-1533, 1999 Jun.