Federal, state and local health authorities across the United States are using dozens of algorithms — some automated systems and others simple prioritization lists — to help determine where vaccines are sent and who can get them.
The formulas generally follow guidelines from the Centers for Disease Control and Prevention to prioritize frontline health care workers, nursing home residents, senior citizens and those with major health risks — and yet public health agencies and medical centers at every level have developed different allocation formulas, based on a variety of ethical and political considerations.
The result: Americans are experiencing wide disparities in vaccine access.
Oregon, for instance, has prioritized teachers over the elderly for Covid shots, an approach that could help schools and businesses reopen. New Jersey has put smokers ahead of educators, which could save lives.
Some prioritization formulas also conflict with one another or impose such prescriptive rules that they hinder immunizations, public health experts say.
Ellen P. Goodman, a professor at Rutgers Law School who studies how governments use automated decision-making systems, said algorithms were needed to efficiently allocate the vaccines. But public agencies and health centers should be transparent about the prioritization formulas, she added.
“We want to know who is using them, what they are trying to do, who owns the proprietary algorithms, whether they are audited,” she said.
A multiagency federal effort — originally called Operation Warp Speed and created by the Trump administration — has managed nationwide vaccine distribution through Tiberius, an online portal developed by Palantir, the data-mining giant. Now the Biden administration, which has retired the program’s name, has taken over and is continuing the effort.
To divvy up doses, federal administrators use a simple algorithm that divides the total amount of vaccine available each week among the 50 states — as well as U.S. territories and a few big cities like New York — based on the number of people over 18 in each place.
Even so, states began warning last fall about Tiberius’s potential drawbacks. In interim vaccine plans filed with the C.D.C., some state health administrators complained that the platform seemed overly cumbersome and that the algorithm’s week-by-week allotments would make it difficult to plan monthslong vaccination campaigns.
Indeed, some health officials and researchers have described the Tiberius algorithm as a black box.
“Why can’t they make public the methods that they use to make these estimations?” said Dr. Rebecca Weintraub, an assistant professor of medicine at Harvard Medical School who was a co-author of a recent study on state vaccination plans. “Why are the states receiving a different number of doses than they expected per week?”
— Natasha Singer