ANCHORAGE, Alaska >> After a middle-aged woman tested positive for COVID-19 in January at her workplace in Fairbanks, public health workers sought answers to questions vital to understanding how the virus was spreading in Alaska’s rugged interior. The woman, they learned, had existing conditions and had not been vaccinated. She had been hospitalized but had recovered. Alaska and many other states have routinely collected that kind of information about people who test positive for the virus. Part of the goal is to paint a detailed picture of how one of the worst scourges in American history evolves and continues to kill hundreds of people daily, despite determined efforts to stop it.

But most of the information about the Fairbanks woman — and tens of millions more infected Americans — remains effectively lost to state and federal public health researchers. Decades of underinvestment in public health information systems has crippled efforts to understand the pandemic, stranding crucial data in incompatible data systems so outmoded that information often must be repeatedly typed in by hand. The data failure, a salient lesson of a pandemic that has killed more than 1 million Americans, will be expensive and time-consuming to fix.

The precise cost in needless illness and death cannot be quantified. The nation’s comparatively low vaccination rate is clearly a major factor in why the United States has recorded the highest COVID death rate among large, wealthy nations. But federal experts are certain that the lack of comprehensive, timely data has also exacted a heavy toll.

“It has been very harmful to our response,” said Dr. Ashish K. Jha, who leads the White House effort to control the pandemic. “It’s made it much harder to respond quickly.”

Details of the Fairbanks woman’s case were scattered among multiple state databases, none of which connect easily to the others, much less to the Centers for Disease Control and Prevention, the federal agency in charge of tracking the virus. Nine months after she fell ill, her information was largely useless to public health researchers because it was impossible to synthesize most of it with data on the roughly 300,000 other Alaskans and the 95 million-plus other Americans who have gotten COVID. Those same antiquated data systems are now hampering the response to the monkeypox outbreak. Once again, state and federal officials are losing time trying to retrieve information from a digital pipeline riddled with huge holes and obstacles.

“We can’t be in a position where we have to do this for every disease and every outbreak,” Dr. Rochelle P. Walensky, the CDC director, said in an interview. “If we have to reinvent the wheel every time we have an outbreak, we will always be months behind.”

The federal government invested heavily over the past decade to modernize the data systems of private hospitals and health care providers, doling out more than $38 billion in incentives to shift to electronic health records. That has enabled doctors and health care systems to share information about patients much more efficiently.

But while the private sector was modernizing its data operations, state and local health departments were largely left with the same fax machines, spreadsheets, emails and phone calls to communicate.

States and localities need $7.84 billion for data modernization over the next five years, according to an estimate by the Council of State and Territorial Epidemiologists and other nonprofit groups. The pandemic has laid bare the consequences of neglect. Countries with national health systems like Israel and, to a lesser extent, Britain were able to get solid, timely answers to questions such as who is being hospitalized with COVID-19 and how well vaccines are working. American health officials, in contrast, have been forced to make do with extrapolations and educated guesses based on a mishmash of data. Facing the wildfirelike spread of the highly contagious omicron variant last December, for example, federal officials urgently needed to know whether omicron was more deadly than the delta variant that had preceded it and whether hospitals would soon be flooded with patients. But they could not get the answer from testing, hospitalization or death data, Walensky said, because it failed to sufficiently distinguish cases by variant.

Instead, the CDC asked Kaiser Permanente of Southern California, a large private health system, to analyze its COVID-19 patients. A preliminary study showed patients hospitalized with omicron were less likely to be hospitalized, need intensive care or die than those infected with delta.