Lessons from an Outbreak: Smallpox in the Hudson Highlands, 1781

The War Years (1775-1783)

July 1, 2020
by Steven Elliott Also by this Author


Journal of the American Revolution is the leading source of knowledge about the American Revolution and Founding Era. We feature smart, groundbreaking research and well-written narratives from expert writers. Our work has been featured by the New York Times, TIME magazine, History Channel, Discovery Channel, Smithsonian, Mental Floss, NPR, and more. Journal of the American Revolution also produces annual hardcover volumes, a branded book series, and the podcast, Dispatches

On January 20, 1781, near New Windsor in the Hudson Highlands of New York, Dr. Samuel Adams wrote a brief entry in the diary he had kept throughout his service as a surgeon attached to the Continental Army’s artillery: “inoculated my waiter and three children of Mr. Smith for the smallpox.”[1] Adams did not seem to take any special notice of this event, for it was one of many medical procedures he recorded in his near-daily diary entries. He was not aware that he was witnessing the early stages of what would become one of the most significant health crises experienced by the Continental Army during the War of Independence. By March, hundreds of his comrades would be ill with smallpox. The army’s medical staff and supplies would be stretched to the breaking point attempting to provide care for them. The commander in chief, Gen. George Washington, would be forced to make difficult decisions regarding whom to treat for this much-feared illness. Exploring why the Continentals experienced a sharp increase of smallpox in 1781 and how they responded has much to teach us about how organizations respond to public health crises.

Smallpox, the disease caused by the variola virus, intermittently struck communities in North America throughout the eighteenth century. It was deadly, highly contagious, and often left its survivors with scarred skin. More positively, smallpox survivors also acquired immunity to the disease. Inoculation, the deliberate infection of a patient with variola, stood out as an effective means of providing this immunity to large populations in a controlled manner. Recipients of inoculations, also known as variolations, typically began to show symptoms after twelve days and then remained contagious for a further two weeks. Thus, a patient would be laid low for nearly a month, but generally experienced much milder symptoms than if he or she contracted the disease naturally. If inoculated people moved around freely before fully recovering, however, they risked infecting others in uncontrolled environments, promising deadlier results.[2]

Most studies of smallpox and inoculation in the American Revolution focus on the war’s early years. The disease spread rapidly in densely-populated cities and military camps, striking occupied Boston in 1775 and the Patriot forces invading Canada in 1776. The movement of large numbers of people over long distances also led to increased infection rates. In late 1776 and early 1777, as soldiers marched from northern New York to reinforce Washington’s troops in New Jersey and new recruits were marshalled in Virginia and Pennsylvania, they spread the infection to their comrades and civilian hosts alike. Shortly after the battle of Princeton, with much of the Patriot army billeted in northern New Jersey’s towns, Washington’s forces faced a health crisis. Uncontained, smallpox threatened his army and surrounding civilians.[3]

The Old Barracks in Trenton, New Jersey, was the site of Continental Army inoculations in 1777. (William M. Brown)

The commander in chief responded by implementing the nation’s first widespread inoculation program. Washington ordered uninfected soldiers to be inoculated near their quarters in New Jersey as well as at recruitment sites throughout the states. Although this mandate temporarily sapped Continental strength, once the soldiers recovered, Washington could effectively campaign with an army possessing immunity. Soldiers would no longer endanger their comrades or the civilian population. Nevertheless, the Continentals continued to face problems with smallpox during subsequent years. Inoculation was only effective as long as it was applied to all new recruits. This required the diligence of officers and civilian leaders overseeing the raising of new forces in the states. Congress lacked the will and authority to enforce such measures, while Washington could not micromanage recruiting officers serving far afield from his headquarters. Consequently, many fresh soldiers arriving at Valley Forge in early 1778 remained vulnerable to the disease. Henceforth, the army handled inoculations in camp rather than at recruitment sites. With the inoculation program well established, variola  presented few problems for Washington or his subordinates between 1778 and 1781. Moreover, recruitment slowed after 1778, meaning most of the soldiers serving in the 1779 and 1780 campaigns were veterans who had undergone inoculation.Regimental surgeons generally handled inoculations for the small number of new soldiers that arrived in camp during these years, requiring little oversight from the commander in chief.[4]

This situation changed in 1781. Many Continentals that had earlier enlisted for three years departed service in the new year. To refill his ranks, Washington relied upon new recruits, many of them six- or nine-month levies. Most of these soldiers arriving at camp in early 1781 lacked immunity. Consequently, regimental surgeons found themselves busy tending to vulnerable Continentals during the new year. The first signs of strain to the army’s medical resources appeared at the artillerists’ quarters near New Windsor, six miles upriver from the main Continental position at West Point. Samuel Adams’ diary revealed his heavy workload beginning in late January as he set to work amid the damp and cold weather. He awoke on January 23 to find the ground covered in sixteen inches of snow and began his morning by inoculating “about 30 soldiers.” After such a busy day he returned to his quarters “much fatigued.”[5] In addition to smallpox treatments, doctors continued to attend to other medical needs. For example, Adams spent most of January 31 assisting in the delivery of an officer’s wife’s baby.[6]

Successful inoculation required adequate care throughout the month-long recovery period. Once men received the infection, they needed warm blankets, comfortable lodging, and adequate provisions. Small luxuries, if they were available, promised to improve soldiers’ mental well-being alongside their physical health. When Adams checked on the state of provisions at the nearest storehouse, he learned to his dismay that it lay destitute of “sugar or any other stores except rice—men will not be happy.” The doctor worried that his disappointed patients might take their displeasure out on him, fearing the men would be “obliged to eat improper food and so the poor surgeon blamed.” Such potential complaints notwithstanding, Adams committed himself to his patients, concluding his entry for January 25 writing “must exert myself for their comfort and safety to the utmost of my power.”[7] The next day Adams drew the meager allotment of plain rice and any other stores he could get his hands on, what nevertheless amounted to “a scanty allowance.” At the end of the month, he was able to supplement his patients’ rice ration with beef, although he still complained that they were “too poorly provided for.”[8]

The inadequate provisions led to complications for the patients as they recovered. At the beginning of February, Adams discovered that several of the inoculated had come down with dysentery. This did not portend well for a more extensive inoculation program. Fortunately for the army in February, the number of vulnerable recruits and their families arriving in camp did not exceed the Continentals’ ability to administer care. Indeed, Dr. Adams reported that several of his patients were emerging from their bout with smallpox by the middle of the month and were nearly ready to return to duty.[9]

While the doctors at the New Windsor artillery park worked to contain to the disease, smallpox began to proliferate through the other Patriot posts in the Hudson Highlands. The army’s lodgings exacerbated the spread of the virus. Since 1778, the Continentals had constructed fortifications, barracks, huts, and storehouses in the region. This military infrastructure provided vital housing for soldiers and storage for their supplies but also increased the population density and facilitated the disease’s spread. The substantial buildings and static nature of the army’s positions along the Hudson also encouraged a large number of noncombatants, including soldiers’ families and sutlers, to congregate in and around the camps. The presence of attached civilians added to the number of inoculations doctors had to administer. For instance, in addition to thirty soldiers Adams inoculated on January 23, he also variolated several of their children. The following day, he inoculated three soldiers, one woman, and three children. Women and children continued to receive inoculations alongside soldiers throughout subsequent weeks.[10]

The movement of soldiers and civilians between posts and towns led to the disease’s spread beyond the artillery park. Maj. Gen. William Heath, the garrison commander at West Point, informed Washington on February 1 that “I am just informed that the Small Pox is in all places in this vicinity and at the Park of Artillery, as there are Some few of the Troops who have not had it, will it not be advisable for such as incline, to have it.”[11] Washington approved preparations for an expansive inoculation program the next day.[12] In his general orders of February 3, Washington ordered all regiments to submit returns of those soldiers who had not had smallpox, thereby providing a list of all men who required inoculations.[13] The returns revealed the army’s vulnerabilities in the wake of the turnover from veterans to new levies. Heath despaired of the uninoculated men, “the number is greater than I apprehended.” He remained optimistic that if the soldiers kept stationary in their Highlands cantonments they could avoid exposure, but this would be impossible come the active campaign season. For his current situation, the major general feared a lack of hospital stores and bed spaces would undermine inoculation efforts. Therefore, Heath held off from ordering variolation at West Point.[14]

Throughout the month, the Patriots clung instead to a strategy isolation to curtail the virus. Nevertheless, the comings and goings of soldiers and civilians from various Highlands cantonments propagated the disease further. Heath reported the increase in variola  infections to Washington at the end of February. He wrote “We have several soldiers taken down with the smallpox; they will be removed and all possible care taken to prevent a spread of the infection. Two or three persons who are supposed to have taken it I have permitted to be inoculated, the latter are of the Connecticut Line.”[15] Despite these efforts, the infection rate increased. Heath recorded in his memoir that by March 16 “The small pox at this time made its appearance in the vicinity of the army and several soldiers were taken down with that distemper.”[16] The next day, the major general announced to the army that “the smallpox, being at Fishkill, New Windsor, Newburgh, and other places in the vicinity of this post,” soldiers that had yet to suffer the infection were “cautioned to be very careful how they go in the way of the infection.” To protect the West Point camps, Heath banned anyone known to have come from an infected house from entering the garrison.[17]

By the end of March, it became clear that smallpox could not be contained solely through quarantine, and inoculation presented the best option for ensuring the army’s health. On March 27, Heath again addressed the illness in his garrison orders. He announced plans to establish a smallpox hospital across the river from West Point. There lay the log huts used as winter quarters by the New Hampshire Brigade. Heath ordered the New Hampshire soldiers that had already had the illness to vacate their huts, thereby opening up space in the huts to isolate and care for inoculation recipients. The vacated New Hampshire huts offered better coverings than tents and were separate from the West Point fortress complex itself, thereby ensuring a measure of isolation for the sick soldiers.[18] Heath estimated the structures could accommodate 240 patients at a time. This would force the Continentals to inoculate vulnerable men and women in stages instead of all at once.[19]

On March 28 Heath sent the healthy New Hampshiremen southwards to man the army’s forward outposts, so that those soldiers that had been on the front lines could return to West Point and receive their inoculations.[20] The remaining vulnerable New Hampshire troops as well as Rhode Islanders returning from outpost duty were to be inoculated “the moment the necessary preparations are made.” They were to be followed by uninoculated soldiers from the rest of the West Point garrison on March 31.[21]

The late March inoculation orders solicited a maximum effort from the army’s medical staff. Heath ordered “surgeons from a brigade or so many in the whole as may be necessary to inoculate and attend the patients are to go with them. The greatest care is to be taken to prevent the spread of the infection.” The general was concerned not only with keeping his army healthy, but also his civilian neighbors. Therefore, Heath enforced a strict quarantine. “All intercourse and visiting is forbidden; limits are to be assigned to the new patients beyond which they are not to pass.” Finally, Heath ordered the construction of a smokehouse that was to be used to disinfect anyone who had to go out from the huts to conduct business elsewhere in the region. Anyone departing the quarantine area was “to be first sufficiently smoked.” As Katy Turner Getty has observed, smoking smallpox patients was a common but ineffective practice in the eighteenth century.[22] More useful was Heath’s strict regulation of access to the quarantine zone. “No person is to come from the huts without the consent of the commanding officer there,” in the form of a written pass. The general viewed this measure as “the best calculated effectually to prevent the spread of the infection.”[23]

Inoculation did not entail a complete suspension of military activity. Soldiers headed to the smallpox hospital were permitted to keep their weapons, as well as “such number of cooking utensils and axes as may be necessary.” Recovering soldiers were still expected to cut wood and cook when they felt up to it. Heath ordered the patients to be “daily kept to moderate exercise at the drill,” although surgeons were to monitor the men’s conditions. With the campaign season approaching, Continental commanders could not overlook training recruits. Heath expressed confidence that the smallpox patients would soon be back to regular duty. Perhaps as a morale-building measure, he reminded their comrades serving in the West Point barracks to keep the vacated rooms clean and tidy, for “they will very soon be wanted for the accommodation of the troops.”[24]

One of the surgeons recalled to assist with the inoculations was James Thacher. Thacher served as a Continental doctor throughout the war, and his Military Journal has provided historians with a superb primary source chronicling daily life in the army. In April 1781, Thacher recorded visiting patients at the hospital across the river from West Point, as well as another to the south at Peekskill. He highlighted the expansiveness of the spring 1781 inoculation program, writing that “all the soldiers, with the women and the children, who have not had the smallpox” were undergoing treatment. In Thacher’s regiment, 187 lay sick with the disease during April. Like Adams before him, Thacher lamented the lack of provisions to keep his charges’ strength up while they recovered. Rice, sugar or molasses, and tea were reserved for those who experienced particularly bad cases, while those enjoying mild bouts subsisted on regular rations of beef and salt pork. He also pointed out that many patients were already weak or sick before receiving their inoculations and were probably not good candidates for the treatment. As he reflected, unfortunately “we were under the necessity of inoculating all, without exception, whatever might be their condition as to health.”[25]

Ultimately, the mass inoculation program proved a limited success. Heath reported to Washington on April 11 that “The small pox patients are in a pretty good way.” Like Adams and Thacher had noted all winter, care suffered due to a lack of provisions. Heath found the army lacking “some hospital stores, such as sugar or molasses, and Indian meal.” He appealed to the commander in chief for relief, inquiring if hospital stores kept in reserve in Connecticut could “possibly be spared may be ordered for the relief of inoculated patients.”[26] On April 12, Washington inspected 500 men recovering from the illness, who Heath described as “in a fine way.”[27] Thacher likewise recorded 500 men recovering in late April, with only four so far having died from the procedure. Yet he noted cryptically that “in other instances, the proportion of deaths is much more considerable.”[28] Given the ongoing shortages of hospital stores, Thacher may have feared continued inoculations would not enjoy such a high success rate. The number of recuperating men exceeded the space Heath had estimated available in the makeshift hospital at the New Hampshire huts by double. With more recruits arriving, it was unclear if the Continentals had the resources to treat them.

The army stood at a crossroads. Without adequate blankets, beds, and food, patients recovering from smallpox might find their health deteriorated even if they survived smallpox itself. Continuing mass inoculations might therefore do more harm than good. With the campaign season approaching, the Patriots could not afford to have a large portion of their rank-and-file waylaid with smallpox and complications deriving from inadequate care. Washington took charge of the situation on April 19, issuing one of his few general orders that year that discussed the disease. “Considering the scarcity of Hospital stores and the advanced season,” the commander in chief declared it “proper to order a discontinuance of inoculation in the army.” Instead, he reinstated the tried methods of quarantine and isolation. To protect newly-arrived recruits from soldiers recovering from the disease (and therefore possibly still contagious), the general commanded “the patients now at the small pox hospital and those who are employed to attend the sick may be prevented from straggling to their corps and all such as do not now belong to the hospital from going to it on any patients until the surgeons report that all danger of infection ceases.” Anyone who developed a case would henceforth be sent immediately to the smallpox hospital, but recruits would no longer undergo inoculation upon their arrival in camp.[29]

Washington’s gamble seems to have paid off. Throughout the remainder of the spring, neither the commander in chief, Heath, or Thacher mentioned smallpox in their writings. Daily orders at West Point focused on drill and camp administration rather than quarantine and inoculation. The makeshift hut hospital across the river from West Point provided a space to quarantine and care for a limited number of cases throughout the spring.[30]

The emergency inoculation and quarantine efforts of March and April 1781 slowed the spread of smallpox among soldiers and civilians in the Hudson Highlands. These measures enabled Washington’s army to take the field with a reasonable degree of health and effectiveness. But, the Patriot force continued to experience a turnover in its ranks, so smallpox remained a threat. Cases began to increase again in late 1781. Just as Heath had feared, a mobile campaign had increased men’s exposure chances. Soldiers taking part in the march to Yorktown were particularly vulnerable. Fortunately, by the winter of 1781-1782, the army enjoyed better provisions and accommodations than in previous years. The death of nine soldiers who had contracted the disease the natural way in January 1782 impelled Continental leaders to act.[31] Uninfected men who had arrived in 1781, as well as the new recruits of 1782 finally received treatment. One officer noted in his diary on January 25, “the whole army under inoculation.”[32] Heath recorded nearly 2,000 men were undergoing the procedure at the end of the month. Several men had died, “but in general it was very favorable.”[33] That the army could treat 2,000 patients with little trouble whereas it had struggled with 500 seven months earlier indicates a much improved supply situation by the start of the new year. Treatment for recruits continued through May 1782. This brought a close to the last health crisis the Patriots faced during the war.

Overall, the Continental Army’s struggles in 1781 highlight the difficulties of containing an infectious disease in wartime. The army learned that the knowledge and practice of a successful treatment was only useful to the extent that it could be administered to everyone. The sharp increase of new arrivals in early 1781 made it difficult for doctors to keep pace with the number of new cases Moreover, medical practitioners had to continue to provide care for more commonplace illnesses and issues even amid the outbreak, spreading resources thin. Food, blankets, medicine, and beds for patients were finite resources that were quickly taxed during outbreaks. Even though the majority of the infected survived inoculation, Washington nevertheless chose to limit its implementation when it became clear that he lacked adequate hospital space and stores to treat more troops. Instead, stringent quarantines helped alleviate the pressure on medical resources even though they were not completely effective in preventing the disease’s dissemination. When it became impossible to limit soldiers’ movements, as during the active campaigns of the summer and fall, infections increased. A sufficient number of doctors, beds, and supplies were available only by early 1782 to inoculate the vulnerable. It took a year-long effort to contain the outbreak, succeeding only after resources were readily available and both inoculation and quarantine measures were first enacted to limit infections.


[1]Samuel Adams Diary, January 20, 1781, New York Public Library.

[2]Anne M. Becker, “Smallpox in Washington’s Army: Strategic Implications of the Disease during the American Revolutionary War,” Journal of Military History 68 (April 2004): 385-86.

[3]Ibid., 387-422.

[4]Ibid., 427-29; Elizabeth A. Fenn, Pox Americana: The Great Smallpox Epidemic of 1775-1782 (New York: Hill and Wang, 2001), 198-202.

[5]Adams Diary, January 23, 1781.

[6]Ibid., January 31, 1781.

[7]Ibid., January 25, 1781.

[8]Ibid., January 30, 1781.

[9]Ibid., February 1-6, 1781.

[10]Ibid., January 23, 24, 30, and 31, 1781.

[11]William Heath to George Washington, February 1, 17181, Founders Online, National Archives, founders.archives.gov/documents/Washington/99-01-02-04723.

[12]Washington to Heath, February 2, 1781, Founders Online, National Archives, founders.archives.gov/documents/Washington/99-01-02-04732.

[13]General Orders, February 3, 1781, Founders Online, National Archives, founders.archives.gov/documents/Washington/99-01-02-04738.

[14]Heath to Washington, February 8, 1781, Founders Online, National Archives, founders.archives.gov/documents/Washington/99-01-02-04794.

[15]Heath to Washington, February 28, 1781, in Collections of the Massachusetts Historical Society, Seventh Series, 5: 140-41.

[16]William Heath, Memoirs of Major General William Heath (New York: William Abbatt, 1901), 257.

[17]Garrison Orders, March 17, 1781, 8th Massachusetts Regiment Orderly Book (March 12-May 17, 1781), Huntington Library.

[18]Garrison Orders, March 27, Ibid.

[19]Heath to Washington, March 25, 1781, Founders Online, National Archives, founders.archives.gov/documents/Washington/99-01-02-05201.

[20]Garrison Orders, March 28, 8th Massachusetts Orderly Book.

[21]Garrison Orders, March 27, Ibid.

[22]Katie Turner Getty, “Smoking the Smallpox Sufferers,” Journal of the American Revolution, January 9, 2020,allthingsliberty.com/2020/01/smoking-the-smallpox-sufferers/.

[23]Garrison Orders, March 29, 1781, 8th Massachusetts Orderly Book.


[25]James Thacher, A Military Journal during the American Revolutionary War, from 1775 to 1783; Describing Interesting Events and Transactions of this Period; with Numerous Historical Sketches of Several General Officers (Boston: Richardson & Lord, 1823), 309.

[26]Heath to Washington, April 11, 1781, Founders Online, National Archives, founders.archives.gov/documents/Washington/99-01-02-05362.

[27]Heath, Memoirs, 260.

[28]Thacher, Military Journal, 309.

[29]General Orders, April 19, 1781. Founders Online, National Archives, founders.archives.gov/documents/Washington/99-01-02-05453.

[30]Alexander Scammell, enclosure in Letter of John Paterson to George Washington, May 16, 1781, Founders Online, National Archives, founders.archives.gov/documents/Washington/99-01-02-05788.

[31]Heath, Memoirs, 301.

[32]Henry Sewall Diary, January 25, 1782, Massachusetts Historical Society.

[33]Heath, Memoirs, 303.

Leave a Reply

Your email address will not be published. Required fields are marked *