The race to figure out just how dangerous the Omicron variant is will likely be a global effort, but some experts are skeptical that the U.S. will play a dominant role.

Why it matters: The CDC has repeatedly come under fire for inadequate data collection throughout the pandemic — and figuring out how to respond to Omicron requires a lot of data that doesn't currently exist.

Where it stands: There are way more questions than answers when it comes to Omicron.

• We don't know whether it can outcompete the Delta variant, which is currently dominant around the world.
• We don't know whether it makes people sicker than Delta does.
• And we don't know how well vaccines or prior infections protect a person against it, or how well current treatments work against it.

What we're watching: "What matters is whether you see over time a significant fraction of U.S. infections become Omicron rather than Delta in areas where there's a head-to-head competition," said Cornell virologist John Moore.

• That would suggest Omicron will replace Delta as the most common COVID variant.
• The other huge data point to look for, Moore said, is how many vaccinated people are hospitalized with Omicron. If there's "a significant number of infected Omicron people in hospital, that would be a significant grounds for concern."

The intrigue: The CDC has been under fire for months for its lackluster tracking of breakthrough infections, and the U.S. was reliant on other countries for real-time data on waning vaccine effectiveness as Delta became dominant over the summer.

• The U.S. may once again be reliant on data from other countries when it comes to understanding Omicron, although that's at least in part because more cases have been detected elsewhere so far.
• The Biden administration talks to South Africa regularly, but doesn't expect basic neutralization data until the end of next week at the earliest. That will give us a much better idea how well vaccines protect against Omicron.

What they're saying: "To the extent we’re constantly relying on Israel, Britain and now South Africa ... that is the definition of flying blind," said Zeke Emanuel, vice provost for global initiatives at the University of Pennsylvania.

• "We're not going to be the first to determine whether vaccine works, what the breakthrough rate is, et cetera, and that's not because we don’t have [Omicron] here," he added.
• Some experts also say that the U.S. still isn't doing enough genomic sequencing, and Emanuel said it's "geographically unrepresentative."

Yes, but: The CDC has drastically improved its genomic sequencing capabilities this year, and is now sequencing one of every seven positive cases found by a PCR test, CDC director Rochelle Walensky said this week.

• The agency is sequencing ten times as many samples each week as it was earlier this year, Walensky said.

The other side: Where data comes from may not matter very much, as long as it's reliable, Moore said.

• "If something is seen in a major European country or Israel or wherever it is, it's going to be the same in the United States ... you've got the global aspect of this to fall back on," Moore said.

The bottom line: We won't understand Omicron until it spreads more, providing more data, and until enough time passes for current infections to translate into hospitalizations.

• In the longer term, the U.S. may need to improve its data collection methods.
• "I think with every passing month, we see more and more glaringly the data deficiencies," Emmanuel said. Congress or the administration "need[s] to set a very clear standard for the data infrastructure we're going to create, and make sure it's real-time data and not modeling."