A Walter Reed Army Medical Center Handbook from 1985 gave an in depth discussion on the proper jet injection technique for prospective Immunization Specialists. The text, Allergy-Clinical Immunology Training Manual, is a conglomeration from previous instructions in corpsman manuals, the Ped-O-Jet manual, and lessons learned from frequent usage. The text sheds light on what the Department of Defense (DoD) knew about jet injectors during the height of their usage.
The digitized text can erroneously be read at face-value posing a risk of spreading misinformation by nefarious actors or illicitly used in third-world nations. Here we will go through the information in the manual and show the errors in thinking, comments which show cross-contamination, and juxtaposition the manual with current knowledge on the risks and hazards of multi-use nozzle jet injectors.
The manual emphasizes using proper technique and maintenance of the jet injector gun.
Improper maintenance and assembly will damage the device, cause faulty operation, and result in contamination of the vaccine. Improper injection technique will injure the recipient’s skin and will fail to deliver the required dosage of vaccine. Prerequisites for learning the use of the jet injection apparatus include:
e. Recognizing that any of the following are indications of faulty maintenance, faulty operation, or faulty injection technique:
( 1 ) Off-center or irregular wheals at site of injection.
( 2 ) Lacerations or bleeding at the site of injection.
( 3 ) Incomplete shots as evidenced by large drops of vaccine remaining on the skin surface.
(Allergy-Clinical Immunology Training Manual, 1985, page 45-2)
Potential for Bleeding
The manual repeatedly stresses the potential for bleeding, beyond the warning cited above:
If the injection site bleeds cotton gauze should be ﬁrmly applied to the area. (Allergy-Clinical Immunology Training Manual, 1985, page 45-3)
Incomplete injections or excessive bleeding will result if injector is not held against the site long enough. (Allergy-Clinical Immunology Training Manual, 1985, page 45-9)
These cautions for bleeding represent ideal usage and not real life conditions. During actual military usage bleeding was common, as evidenced by the testimonies of veterans and evidenced within the links below:
Erroneous Claims on Safety
The greatest threat posed in the Manual is the claim that the device is safe. The manual states,
Large numbers of personnel can be processed rapidly with minimal hazard of transmitting infection when the jet injector is used. (Allergy-Clinical Immunology Training Manual, 1985, page 45-2)
Here the DoD minimizes the risk of cross-contamination as a “minimal hazard of transmitting infection.” Yet minimal hazard is not the same as no hazard. The language follows DoD’s longstanding modus operandi of acknowledging the possibility of transmission and then minimizing the likelihood.
The manual further states,
Since the piston, front end assembly, and the feed needle are sterilized at the end of every day’s use, there is little chance of contamination. (Allergy-Clinical Immunology Training Manual, 1985, page 45-2)
The sterilization of the jet gun at the end of the day does nothing to stop cross-contamination during the mass vaccination of 100 to 300 vaccinees within that day. DoD backs this preposterous claim by stating in the following sentence,
Even though the nozzle is not sterilized between recipients, there has been no evidence of serum contamination or transmission of disease. (Allergy-Clinical Immunology Training Manual, 1985, page 45-2)
Yet this is not true. In 1959, Abram Benenson, the co-inventor of the Ped-O-Jet, and researchers at Walt Reed Army Institute of Research conducted safety testing on the Ped-O-Jet. The researchers concluded “the problem of hepatitis has been minimized” after “the presence of less than 15 gammas of human serum” was detected on the nozzle of the Ped-O-Jet (Benenson, 1959). In 1959, the risk of cross-contamination existed but was minimized by the researchers. Therefore, it is incorrect for this 1985 manual to state no serum contamination existed when evidence existed to the contrary.
Note: Since 1959, greater advances in science have been made. As Jet Infectors has previously written, the results [of Benenson’s study] were unable to detect any contamination using the assays available during that era…the science of the late 1950s could not detect contamination within such microscopic levels, and most importantly, no tests existed to detect viral hepatitis.
It was true there was no evidence of disease transmission at the time of the manual’s publication in April of 1985. Yet the DoD never implemented any seroepidemiological study, nor active surveillance program following jet injector immunizations. Of course, they would not ﬁnd what they were not looking for.
Interestingly, days before publication of this manual an outbreak from jet injector usage came under investigation by the Long Beach Department of Health (March 1985) (CDC, 1986) and a laboratory study implicating jet injector transmission was published (March 1985) (Brink et al., 1985).
Moreover, the DoD’s assertion that there was no evidence of blood or disease transmission conveniently ignores the fact that the DoD knew of the risk of cross-contamination by ﬂuid-suck back when it was raised by inventor Aaron Ismach in 1959 and were still attempting to overcome the risk of ﬂuid-suck in the Ped-O-Jet as outlined within their 1967 military speciﬁcation.
The manual itself even inconspicuously acknowledges the phenomenon of ﬂuid-suck back when it cautions against foreign particles entering and clogging the nozzle. The manual states,
Every attempt has been made to prevent foreign matter from entering the unit and plugging the jet nozzle. If plugged, the tip may be cleared through the use of the cleaning wire provided…A damaged nozzle will seriously affect the proper operation of the injector. If nozzle opening is enlarged or leading edges of the opening is made ragged, excessive bleeding may result. (Allergy-Clinical Immunology Training Manual, 1985, page 45-7)
What is the foreign matter? The word foreign, in this regard, is deﬁned as coming or introduced from outside. The vaccine is the only matter expected to be involved in the jet injection. The vaccine comes from within and not outside. So what is the foreign matter that comes from outside and enters the jet nozzle? Maybe it is backsplash of vaccine after impinging the skin? Blood? Skin from the creation of hole formation? Any foreign matter entering the unit should have been recognized as contamination, in which case the Ped-O-Jet was not sterile.
The wise critic may retort if the jet gun is clogged then there is no cross-contamination because the gun is in need of repair. However, this point misses the mark. The jet injector has been propagated as being a safe method of vaccination that is impervious to cross-contamination. If the jet injector were impervious then no foreign matter could inﬁltrate the jet nozzle. Yet here is acknowledgement within a DoD manual warning foreign matter is capable of such inﬁltration.
Said differently, either the Ped-O-Jet is impervious to cross-contamination as propagated by the DoD or the Ped-O-Jet is susceptible to being inﬁltrated as the DoD has warned, but it cannot be that both hold truth. Here the former is a pufﬁng statement minimizing the risks of jet injectors and the latter a stark admission of reality—jet injectors were susceptible to becoming contaminated and capable of cross-contaminating.
The full manual can be viewed here.
• (Allergy-Clinical Immunology Training Manual, 1985) Allergy-Clinical Immunology Training Manual, Volume II. Walter Reed Army Medical Center, April 1985. Fourth Edition. pp. 45-1 – 45-10.
• (Benenson, 1959) Benenson AS. Mass immunization by jet injection. In: Proceedings of the International Symposium of Immunology, Opatija, Yugoslavia, 28 September—1 October 1959 (International Committee for Microbiological Standardization, Secton of the International Association of Microbiological Societies). Zagreb: Tiskara Izdavackog zavoda Jugoslavenske akademije; 1959;393–399 [Library of Congress QW 504 I60p 1959].
• (Brink et al., 1985) Brink PRG, van Loon AM, Trommelen JCM, Gribnau FWJ, SmaleNovakova IRO. Virus transmission by subcutaneous jet injection. J Med Microbiol. December 1985; 20(3): 393-397.
• (CDC, 1986) Centers of Disease Control. Epidemiologic Notes and Reports Hepatitis B Associated with Jet Gun Injection — California. MMWR 1986;35(23):373-376.