Most American doctors cannot determine which variant of the coronavirus a patient is carrying, a distinction that could mean the difference between life and death.
High-risk patients carrying the Delta variant may benefit greatly from two specific monoclonal antibody treatments that have been shown to reduce hospitalization and death. But those drugs most likely wouldn’t do anything for patients with Omicron, who would only respond to a third antibody treatment that is very scarce.
While US officials have agreed to use a temporary test that could identify Omicron’s genetic signature, experts say it’s not feasible for major health systems dealing with a stack of patients in each case.
That makes treating patients challenging in places like Maryland, where cases are on the rise and Omicron accounts for about 58 percent of them. The Delta variety also holds up in the Great Plains and parts of the west, including California.
While there is no approved test to determine each individual’s variant, a national network of state and other labs uses genome sequencing testing to broadly track variants in communities. Health systems then use those regional estimates or their own data to decide which antibody treatments to use in their clinics and hospitals.
Many of them concluded that a community of largely Delta patients would benefit most from the antibody drugs made by Regeneron and Eli Lilly, while communities where Omicron patients predominate would benefit from antibodies from GlaxoSmithKline and Vir Biotechnology.
Federal officials have dabbled in making the decision for the nation. On December 23, they stopped shipping antibody treatments from Eli Lilly and Regeneron after the Centers for Disease Control and Prevention said 73 percent of U.S. Covid cases were Omicron.
A indignation followed by Republican political leaders, who claimed that some people in their states were still infected with Delta. And on Tuesday, the CDC lowered its estimate of Omicron cases nationwide to 59 percent. On December 31, federal officials will resume national shipments of all antibody treatments.
In the coming weeks, as the country grapples with this unequal mix of both variants, it will be “extremely difficult” to tailor treatments to each patient,” said Dr. Alex Greninger, deputy director of the University’s clinical virology labs. of Washington Medical Center. .
dr. Greninger is credited with developing one of the first tests to detect the coronavirus in the United States. But he’s pessimistic that health systems could turn quickly to determine which patients have Delta or Omicron. And while a keyboard shortcut can detect Omicron, there’s no easy way to report the results in bulk, he said.
In addition, the genome sequencing used by public health officials takes nearly a week — too long to target the early antibody treatments that have been found to reduce the need for hospitalizations. That makes patient care especially difficult right now, said Dr. Mark Siedner, an infectious disease physician and researcher at Massachusetts General Hospital.
In Massachusetts and nearby states, an estimated 44.5 percent of cases are Omicron. dr. Siedner said his health system has stopped using the Regeneron and Eli Lilly antibodies that are ineffective against Omicron and is “waiting anxiously” for more doses of the effective treatment by GlaxoSmithKline and Vir Biotechnology.
“We’re in a set pattern and it’s a terrible time to be in that place,” he said.
