Smallpox and Vaccination in the Civil War

Terry Reimer

Originally published in Winter 2004 in the Surgeon’s Call

Smallpox was one of the many diseases challenging medical personnel during the Civil War.  Unlike most other diseases, the surgeons of the time had an effective way to prevent smallpox using vaccination and to control outbreaks through the isolation of its victims.

Inoculation and Vaccination

Inoculation was in widespread use by the 1720’s.  It is the introduction of disease agents into the body to produce a mild form of the disease, usually done by using pus or scabs from infected persons that was administered to the patient through small cuts made in the skin.  It was intended to confer immunity by producing a mild case of the disease.  Unfortunately, not all cases were mild and deaths were associated with inoculation, but at a far lesser rate than among those naturally acquiring the disease.  Despite the danger, inoculation was widely practiced throughout the eighteenth century.

Vaccination was developed in 1798 by Edward Jenner.  For smallpox, cowpox serum was used, since cowpox is a closely related disease and created a resistance to smallpox.  Like inoculation, the vaccine was administered through a series of small cuts in the skin, usually in the arm.  The cowpox virus was obtained from animals infected with cowpox either naturally or by intent.  By the 1830’s, vaccination was widely accepted, especially among physicians.  Inoculation was still practiced in some places until it was outlawed by individual states.  New York banned inoculation in 1816, and in 1850 Maryland followed suit.  The bans were based on the fear of spreading the disease through inoculated persons since they were infectious, unlike vaccinated persons.  By the outbreak of the war, inoculation was illegal in most places, but still occasionally practiced.

The preventive measures of vaccination and isolation drastically reduced the occurrence of smallpox in the early to mid-nineteenth century.  By the 1840’s, vaccination was beginning to be neglected and there was a generation of Americans who had never been exposed to the disease.  As a result, the incidence of smallpox began to rise in the decades before the Civil War.

Smallpox and Vaccination During the Civil War

From May 1861 to June 1866, there were 12,236 reported cases of smallpox among white troops in the Union Army, or 5.5 per thousand men annually.  In addition, there were 6,716 cases among the U.S. Colored Troops, or 36.6 per thousand men annually.  The death rates from the disease were approximately 23 percent for the white troops and 35 percent for the colored troops.  Quarantine, vaccination, and the destruction of infected clothes and bedding were the primary tools used to control the spread of smallpox in the armies.  Most hospitals had a separate ward, or even a separate hospital, in which to isolate smallpox patients since the disease was known to be contagious.

Both Union and Confederate regulations required the vaccination, and re-vaccination if necessary, of all troops.  Often this objective was not met since most regiments were raised by the individual states and the regulation was disregarded in the rush to send large numbers of men into battle.  Since there had been no systemic vaccination of the civilian populations, many of the recruits had never been vaccinated or exposed to smallpox.  Re-vaccination was recommended after seven years had elapsed from the last vaccination, or when men were directly exposed to the disease.

The best and purest source for vaccine was from cows or calves.  The crust from the cowpox pustules were used as the source of the virus.  The pressing demands of war often led authorities to institute programs that obtained the scabs from vaccinated humans.  The Union medical dispensaries of the northern cities supplied vaccine virus in the form of crusts taken from vaccinated infants, each with a certificate listing the dispensary and the child’s name.  Crusts were also supplied from cows, in at least one instance from calves infected with the “humanized” virus, not naturally occurring cowpox.

In the Confederacy, many programs were set up to assure an adequate supply of vaccine scabs for the army.  Every hospital had a medical officer whose job was to search the surrounding populace for children on whom they could propagate the virus.  Ads were taken out in local papers offering free vaccination to children if the crusts were then allowed to be harvested.  Both white and African American children were used to supply scabs, and in at least one instance a small group of African American children were kept vaccinated to provide usable material.  The children were vaccinated in six places in each arm.  In two weeks the crusts were removed, wrapped in tin foil, and shipped to army surgeons.  Late in the war, a shortage of virus material led to an authorization to pay private physicians five dollars per usable scab.

Children and cows were the safest sources for crusts, but there were many documented instances where other methods were used.  Surgeons often used the scabs from recently vaccinated men to vaccinate other soldiers.  Soldiers did the same among themselves, sharing the crusts and using knives to make the incisions in their arms.  Some men even sent scabs home for the use of their families.  In most of these cases, the appearance of the scab and the proper number of days from the initial vaccination were not taken into account.

Spurious Vaccine

Unfavorable results from vaccination were all too common.  Even pure vaccine, obtained from official Army dispensaries, had instances of complications.  Possible reasons were that faulty preservation of the crusts made them lose effectiveness, or that they had been contaminated in some way.  Occasionally, the vaccine did not “take” and did not produce the major reaction at the vaccination site that was expected from a successful vaccine.  In other cases the site of the vaccination became overly sore and swollen, and abnormal pustules developed.  These uncharacteristic developments made the surgeons question whether the vaccine had been effective.

Complications from using a scab from a recently vaccinated adult were even more deleterious.  Since many vaccinations took place in the hospitals, crusts from men who were sick with other conditions were occasionally used, spreading disease rather than preventing it.  The surgeons also noted that vaccinating men who were in poor condition due to other illnesses led to a higher number of patients suffering constitutional effects, some even fatal.  Many times, vaccination was not done until smallpox appeared in a hospital or prison.  Vaccinating at this time was effective, but increased the chance of spreading disease in already indisposed populations.

Perhaps the worst, and unfortunately common, form of spurious vaccination was the use of scabs that were syphilitic in nature.  This occurred both in the hospitals and among the soldiers who self-vaccinated.  Misdiagnosing a scab or harvesting crusts from the arm of a soldier who had syphilis, would spread this disease to everyone vaccinated from that source.  In one notable case,  two brigades were affected by a vaccination infection that was thought to be syphilitic in nature.  The men were so sick that the brigades were unfit for military service.  The epidemic was traced to a single soldier who had obtained vaccination material from a young lady of possibly questionable character.

The Confederate Medical department attempted to prohibit soldier-to-soldier vaccination in order to limit these deleterious effects.  Harmful results were much less likely with crusts harvested from children or cows.  Even civilians were discouraged from self-vaccination, as the consequences of spurious vaccine had spread to the general population as well, leading to a mistrust of the vaccination process.

Conclusion

Research into the history of smallpox vaccinations led to the discovery that the actual virus used in vaccinations was the vaccinia virus, of the same family as the smallpox (variola) and cowpox viruses, but genetically distinct.  The origins of the vaccinia virus are unknown, but it is believed to have originated in the nineteenth century.

The preventive measures of vaccination and isolation taken by the Union and Confederate Medical Departments curbed the occurrence of smallpox during the war and averted any major outbreaks.  The success of the vaccination of soldiers during the Civil War led to widespread vaccination of the civilian population after the war, further helping to control this serious disease.

About the Author

Terry Reimer is presently the Director of Research the National Museum of Civil War Medicine in Frederick, Maryland. Previous work includes over twenty years of experience in historical archaeology and research, specializing in 17th, 18th and 19th century American sites.  She holds a B.A. in Anthropology from the University of Maryland and did graduate work in anthropology and folklore studies at George Washington University. She is the author of two books, One Vast Hospital: the Civil War Hospital Sites in Frederick, Maryland after Antietam and Divided by Conflict, United by Compassion: The National Museum of Civil War Medicine, and the co-author of two other books, Bad Doctors: Military Justice Proceedings Against 622 Civil War Surgeons and Caleb Dorsey Baer: Frederick, Maryland’s Confederate Surgeon.