More than 180 years ago, the federal government launched the largest effort of its kind in the United States to vaccinate Native Americans against the deadly disease of smallpox.

With it ravaging Native American communities in the 1830s, the disease became a widespread public health crisis and threatened to curtail the government’s massive effort to force thousands of Native Americans from their lands in the East and push them West to reservations.

In 1832, Congress passed legislation — the Indian Vaccination Act — that allowed the federal government to use about $17,000 to hire doctors to vaccinate Native Americans who were living near White frontier settlements. Many White settlers feared that Indians would spread the disease to them.

The act was intended to vaccinate Indians against smallpox but for entirely mercenary reasons, according to Regis Pecos, a member of the Pueblo de Cochiti tribe in New Mexico.

“It wasn’t in the interest of Indian people,” said Pecos, who is also co-director of the Leadership Institute at the Santa Fe Indian School. “It was a way of vaccinating them to move them so White Americans could move them into Western lands.”

Fast forward to the 21st century, when the coronavirus pandemic has swept through the more than 500 federally recognized tribes in the United States and devastated some tribal communities. Native Americans have among the worst infection rates in the country — nearly three times higher than the overall U.S. population.

Tribes across the country are racing to get vaccine doses to their members and launching messaging campaigns to try to persuade Native Americans who may be reluctant to take them. The level of reluctance to take a vaccine stems from decades of mistrust between sovereign nations and the federal government, according to Native American medical experts, including over medical and scientific studies that were conducted in unethical ways.

“Historical trauma over these past wrongs is embedded in the DNA for some of our people,” said Dakotah Lane, a doctor and member of the Lummi Nation, recently told Indian Country Today.

“We need to remember that our communities have survived TB and smallpox, and a long history of lies and wrongdoing by the federal government,” said Lane, who is also the Lummi’s health director.

Donald Warne, an Oglala Lakota doctor from the Pine Ridge Reservation, said the Indian Removal Act, the massacre at Wounded Knee and other atrocities have contributed to vaccine hesitancy. And so has the memory of the distribution of blankets infected with smallpox, which he calls “the first documented case of bioterrorism with the purpose of killing American Indians.”

When the vaccinations started to roll out to communities across the United States, Anthony S. Fauci, the nation’s top infectious-disease doctor, announced on national television, “The cavalry is coming!”

For Native Americans, the reference to the cavalry was disturbing, not reassuring.

“To Indian people, it signifies the beginning of a massacre. It references the threat of soldiers on horseback during the Indian Wars,” Pecos said.

The history of Native Americans being mistreated in scientific and medical research is lengthy.

In the 1990s, a DNA study done among the Havasupai Tribe in Arizona took blood samples from tribal members in what was supposed to be a survey on high rates of diabetes. But the samples were used in unauthorized studies that challenged the tribe’s traditional ways of teaching. Arizona State University, which helped oversee the study, eventually settled and paid the Havasupai $700,000 after the tribe filed a lawsuit.

In 1975, Government Accountability Office investigators found that medical studies and drug treatments — overseen by the Indian Health Service — had been done without parents’ consent on Native American kids who suffered from trachoma, an infectious eye disease caused by bacteria, at Indian boarding schools in the late 1960s and early 1970s.

Because the IHS oversaw boarding schools, the agency and the Proctor Foundation for Research in Ophthalmology at the University of California, which did the trachoma experiments, defended their work without consent, saying they “believed it was not necessary since IHS acts as legal guardian for the children while they attend the boarding schools.”

At one point, the researchers told investigators that because the medical studies had started and the “school year was already underway, they believed that it would confuse the parents if they began seeking informed consent at that time.”

Another case the GAO looked at from the 1970s found that more than 3,400 Native American women under 21 who suffered from mental health issues were involuntarily sterilized in parts of Arizona, Oklahoma and New Mexico.

The sterilizations, the report said, were not classified as “voluntary and therapeutic” in the IHS system.

Similarly, at the White Mountain Apache reservation in Arizona, studies for pulmonary disease were done among Native American children, but overseers later found that parents in many instances had not given full consent for testing.

That type of history in medical abuse cases resonates in what Pecos calls “generational trauma.”

“There are older members in our communities who have lived and experienced those times, or their parents, grandparents or great-grandparents did, and they remember,” Pecos said. “It is not just something in a distant past.”

At Lane’s tribe, the Lummi Nation outside Bellingham, Wash., there are still many tribal elders and other members who recall how researchers came onto the reservation in the early 1980s and asked to do research on children with problems.

The tribe gave an “informal consent” to the researcher, according to Lane. He said the researcher interviewed families and kids and eventually took pictures and used them in educational classes for others in the medical community.

But some of the families who had participated in the research were not clearly told that their child had fetal alcohol syndrome and were surprised when they saw their pictures being used in presentations and hearing that they had the disease.

“Some got up and said, ‘I didn’t know that,’ ” Lane said. “ ‘How dare you use that picture.’ ”

The tribe later formed a review board that oversees and approves any scientific research done at the reservation and to tribal members, and that group has been actively involved in reviewing the tribe’s participation in vaccinations against the coronavirus.

In the Navajo Nation, the largest tribe that occupies land stretching across New Mexico, Arizona and Utah, many members still vividly remember how researchers came to the reservation in the 1990s and wanted to look at an outbreak of the “hantavirus,” a pulmonary illness that was dubbed the “Navajo flu” by some researchers.

The disease “stigmatized the Navajo and led them to develop and tighten their response and participation in medical research,” according to Lane.

This winter, Navajo Nation President Jonathan Nez encouraged the roughly 173,000 people who live on the reservation to get vaccinated against the coronavirus, which has devastated their community. He said tribal leaders have worked hard to overcome the “distrust in Indian Country of government” and science.

But during the brutal smallpox outbreak nearly two centuries ago, politics played a role in the rollout of the vaccine for Native Americans, as officials used their positions to “selectively protect American Indian nations who were involved in treaties favorable to the U.S.,” J. Diane Pearson wrote in an article for the University of Minnesota Press called “Lewis Cass and the Politics of Disease: The Indian Vaccination Act of 1832.”

“Indian nations viewed as aggressor nations” were not vaccinated, Pearson said.

In Ohio, the Seneca and Shawnee tribes had chiefs who refused to leave their lands to head west because they had heard of the smallpox epidemic wiping out tribes west of the Mississippi River. One group of Chickasaws “who were unprotected from smallpox were moved into a country ablaze with smallpox,” Pearson wrote.

“Vaccinations,” Pearson wrote, “were used to enable Indian removal, to permit relocation of Native Americans to reservations, to consolidate and compact reservation communities, to expedite westward expansion of the United States, and to protect Indian nations viewed as friendly or economically important to the United States.”

The smallpox epidemic nearly wiped out three tribes — the Mandan, Arikara and Hidatsa. Their combined population plummeted from 10,000 to 160 in one year. They combined to stay alive and are what’s now known as the Three Affiliated Tribes in central North Dakota.

In 1838, an agent overseeing the Sioux in South Dakota reported to a government superintendent how some Native Americans in the Great Plains were being wiped out from smallpox they’d gotten from White traders. Joshua Pilcher, a 47-year-old Virginian, wrote that “half of the Hidatsa had died, as had half of the Arikara,” according to a 2005 article in the Smithsonian Magazine.

“The great band of [Assiniboine], say 10,000 strong, and the Crees numbering about 3,000 have been almost annihilated. … The disease had reached the Blackfeet of the Rocky Mountains,” Pilcher wrote. “All the Indians on the Columbia River as far as the Pacific Ocean will share the fate of those before alluded to.”

The Indians of the Great Plains, Pilcher said, were “literally depopulated and converted into one great graveyard.”

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