sign in sign up
<<
Home , Polio vaccine

Swine Fluand : Some Parallelsand Some Differences

Howard B. Baumel College of Staten Island of the City Universityof New York Staten Island 10301

The swine flu vaccinationprogram could be successfullydevel- facturedby a single pharmaceutical generated debate in scientific and oped. company.The cause of this outbreak

medical circlesthat extended to the Salkrelied heavily on his previous was never clearly established. Be- Downloaded from http://online.ucpress.edu/abt/article-pdf/39/9/550/36038/4446085.pdf by guest on 29 September 2021 general public.The controversythat experience as he attemptedto pro- cause bottles of tissue culture fluid centered on the vaccine's effective- duce a killedvirus .He containingthe virushad been stored ness and safety was reminiscentof used formalinto kill the and priorto being treated with formalin, the problemsthat accompaniedthe isolated one strain for each of the it was possiblethat bits of tissue had development of the polio vaccine three knowntypes of polio virus.To settled to the bottom covering the years ago. A review of that earlier determineif any live virusremained and protecting them from scientific achievement can provide after the exposure to formalin,the the formalin.To prevent this, the insightsinto the swineflu dilemma. treated virus was injected into the tissue culture fluid was filtered to By the mid-1930's,only threeviral brain of a monkey. If the monkey remove the debris before exposure diseases,smallpox, rabies, and yellow contracted polio, it was concluded to formalin. fever, had yielded to vaccines. In that live viruswas present.To deter- HeraldCox and HilaryKoprowski each of these cases, the vaccine mine if the treated virus was effec- (1955, 1956) had developed an consisted of a live virus. In 1936, tive, Salk injected it into monkeys attenuatedvirus vaccine that could AlbertSabin was able to grow polio whose blood was then tested for the be administeredorally. Proponents virus in nerve cells, but this pro- presence of antibodies. Based on of a live vaccine contended that it cedure, when used for vaccine pro- these tests, the vaccine was pro- would immunizemany people who duction,entailed the riskof transmit- nounced safe and effective (Salk were not vaccinatedbut had come ting encephalitiswith bits of infected 1953). into contact with those who were, nervetissue. Since antibody production in since unvaccinated individuals John Enders (1949) was able to monkeys did not assure similar could catch a generally harmless grow virusin a culturecon- formationin humans,human testing that would result in their sisting of human embryonictissue. was the next step. By March 1954, .Trials of this vaccine His success in growing polio virus 7,000 childrenhad been successfully in 1956 revealed that vaccinated insertedinto culturesleft over from immunizedwith the Salk vaccine.A individualsexcreted large amounts his mumps experiments demon- massive testing program was then of viruswith theirfeces and that the stratedthat the polio viruscould be begun with 441,131 childrenreceiv- excreted virus had revertedto viru- grownin non-nervoustissue. ing the vaccine, and 201,229 chil- lence as it passed throughthe intesti- Thomas Francisand dren receiving placebos (Francis nal tract. Further work with this developed a killed influenza virus 1955). Sabinand Endersconsidered vaccinewas curtailed. vaccine. In their efforts to produce testing of Salk'svaccine at this time In 1954, Sabinhad begun looking the flu vaccine, they encountered premature;however, the vaccinewas for and isolatingmutant virus strains problemsrelated to: (1) the amount 60-70% effective against Type I that were non-virulentbut still anti- of formalinneeded to kill the virus; polio virus (the most frequentcause genic. Russian virologistsapproved (2) whichtypes and strainsof viruses of paralyticpolio), and over 90% the three strainsof attenuatedvirus to includein the vaccine;and (3) the effective against Types II and III. that Sabinfinally selected and agreed variationsin the stabilityof strains, Two hours afterthese findingswere to fieldtest the vaccinein the Soviet with some strainsshowing low viru- announced, the Salk vaccine was Union. By 1960, fifteenmillion peo- lence in trialsreverting to licensed for production.During the ple had successfullybeen vaccinated when they were injected as a vac- same month, about 250 children with Sabin's vaccine; and in 1961, cine. These same problems would developed paralyticpolio withinten it receivedAmerican Medical Associ- have to be resolved before a polio days of receivingthe vaccine manu- ation approval. The vaccine con-

550 THEAMERICAN BIOLOGY TEACHER, DECEMBER 1977 sisted of sugarcubes moistenedwith or that a differentlethal strainmight surroundingthe vaccine remains. live virus suspensionor live virusin strike. Our efforts should be directed to spoonfulsof syrup.In 1963, eighteen Now in the aftermathof the swine resolvingthe questionsand dispelling cases of paralytic polio definitely flu vaccinationprogram, we can see the doubtssurrounding the vaccine. associatedwith the vaccinehad been which of the anticipatedconcerns reportedamong the seventy million materializedand what the significant References Americanswho swallowed the full differenceswere between these two of three strains. (Schoen- attemptsat massimmunization. ENDERS,J. F., WELLER,T. H., and course ROBBINS,F. C. 1949. Cultivationof berger 1976). A small risk with the Polio vaccine was introduced the Lansing strain of poliomyelitis vaccinefor individualsover eighteen when many people knew someone virus in cultures of various human years old was acknowledged.Salk who had alreadysuffered from the embryonictissues. Science 109:85. vaccine supporterssuggest that the disease. Even after the production FRANCIS,T., JR. 1955. Evaluationof number of Sabin vaccine induced error that led to paralysis among the 1954 poliomyelitisvaccine (Salk) field trial. Journal of the American cases of paralyticpolio would have recipientsof a bad batch of vaccine, Medical Association 158:1266. been higherif the early oral vaccine the public still came to clinics for KOPROWSKI,H. 1955. Immunization swallowersin the United States had .No outbreakof swine of man against poliomyelitis with Downloaded from http://online.ucpress.edu/abt/article-pdf/39/9/550/36038/4446085.pdf by guest on 29 September 2021 not been protectedby the Salk vac- flu has occurredsince the episode at attenuatedpreparations of livingvirus. cine. Fort Dix in January 1976 that trig- Annals of the New York Academy of Sciences 61:1039. There always was a controversy gered the nationalcampaign, so the RAMOS-ALVAREZ,M. and SABIN, regardingthe relative merits of the publichas no directexperience with A. B. 1954. Characteristicsof polio- Salkand Sabinvaccines. In 1973, on the disease. With the outbreak of myelitis and other enteric viruses the twentieth anniversary of the the rare Guillain-Barreparalytic recovered in tissue culture from announcement of a polio vaccine, syndrome among some persons healthy Americanchildren. Proceed- ings of the Society for Experimental Salkindicated that he consideredthe vaccinatedwith the swineflu vaccine, Biology and Medicine 87:655. switch from his killed virus vaccine came publicskepticism regarding the ROCA-GARCIA,M., KOPROWSKI,H., to Sabin's live, attenuated one ill- necessityof immunization. JERVIS, G. A., NORTON, T. W., advised and unnecessary.He cited Because there was no incidence NELSON,T. L. and COX,H. R. 1956. the small,but consistent,incidence of on the efficacy Immunizationof humanswith a chick of swineflu, questions embryoadapted strain of MEF1polio- polio among recipientsof the Sabin of the vaccine cannot be answered. myelitisvirus. Journal of vaccine each year comparedto the Virologists generally agree that 77:123. lackof even a singlecase in countries because ,of the tendency of the SABIN,A. B., and OLITSKY,P. K. 1936. where the Salk vaccine was used influenzavirus to change structure Cultivationof poliomyelitisvirus in exclusively.Salk maintainsthat the and therebyrender existing vaccines vitro in human embryonic nervous tissue. Proceedings of the Society for Sabin vaccine may pose more of a ineffective, influenza vaccines are Experimental Biology and Medicine threatthan naturallyoccurring polio, less effectivethan vaccines used to 34:357. and he believes that people in the combat certainother diseases, such . 1955. Behavior of - United States should have a choice as polio, measles,mumps, and small- avirulent poliomyelitis viruses in of eitherthe live or killedvirus vac- pox. Because of the known number experimentallyinfected human volun- teers. Pediatrics 12:471. cines. Because the Salk vaccine is and antigenic stabilityof the polio SALK, J. E. 1953. Recent studies on no longer manufacturedor distrib- viruses, all of the antigenic types immunization against poliomyelitis. uted here,that option is nonexistent. could be includedin the polio vac- Pediatrics 12:471. Many of the concerns expressed cine. This is more difficultto accom- . 1973. Polio: a cure for the new about the swine flu vaccine priorto plishwith the influenzavirus because controversy.The New York Times, 26 May 1973. immunizationcampaign were the. of its antigenicvariability and unde- , and SALK, D. 1977. Control of remarkablysimilar to those that the terminednumber of subtypes. influenzaand poliomyelitiswith killed developers of the polio vaccine Two real hazards are present in virusvaccines. Science 195:834. confronted.These included:possible any mass immunizationeffort. Some SCHOENBERGER,L. B., MCGOWAN, adverse reactionsin children;possi- batchesof vaccinesmay be imperfect J. E., JR., and GREGG,M. B. 1976. not Vaccine associated poliomyelitis in ble long-termhazards that had and produce unexpected effects, as the United States 1961-1972. Ameri- surfacedduring clinical trials of the was the case with the polio vaccine. can Journal of 104:202. vaccine;possible errors in the manu- Or, deaths and other complications factureof the vaccine;effectiveness can occur coincidentallywith vac- of the antibodylevels produced by cine administration,as occurredwith the vaccine if the recipientencoun - the swine flu vaccine.The winterof Nothing great was ever achieved tered the disease;and the possibility 1976-77 passed without any swine without enthusiasm. that the virus might change its form flu epidemic, but the controversy Ralph Waldo Emerson

PERSPECTIVES 551