Preliminary findings in a report published this month reveal that Asian Americans accounted for 52 percent of COVID-19 deaths in San Francisco.
The research, published by the Asian American Research Center on Health, pulled data from May 5 from the City and County of San Francisco's COVID-19 demographics report. The municipalities at the time had recorded a total of 1,754 cases and 31 deaths. Of those deaths, 16 were of Asian Americans.
Researchers said Asian Americans constituted 13.7 percent of all cases of infections in San Francisco but had the highest proportion of deaths to cases across all racial groups. The group's proportion of deaths to cases also exceeded that of California as a whole.
A co-author of the study, Dr. Tung Nguyen, a professor of medicine at the University of California, San Francisco, said the recorded number of deaths was not large enough to draw statistically significant conclusions from. But in a county where Asian Americans account for about 35 percent of the population, the group's mortality rates associated with the coronavirus are concerning, he added.
"We're not claiming there is an actual significant mortality disparity," Nguyen told NBC Asian America. "The purpose of the research brief is to say something might be going on and we need more data."
Full coverage of the coronavirus outbreak
Since the report was first published, the COVID-19 mortality rate for Asian Americans in San Francisco has dipped slightly, to about 49 percent.
The findings raise questions about the scale of testing in San Francisco, Nguyen said. The numbers showing a low infection rate among Asian Americans — which contribute to the figures showing a higher mortality rate — may be driven by disparities in testing and diagnosis, he said.
"The findings in this report shed light on the underlying health disparities and other social inequities Asian American communities have faced for decades, which are further exacerbated amid the COVID-19 pandemic," Jeffrey B. Caballero, executive director of the nonprofit Association of Asian Pacific Community Health Organizations, said in an email.
Nguyen said part of the reason researchers pushed to publish the data despite the small numbers is to challenge the idea that Asian Americans are healthier than the general population.
"In some health metrics it's true," he said. "But we don't want people to think when it comes to COVID, Asian Americans are any more protected, because then of course they won't do the right thing to keep themselves from getting infected and dying from it."
Researchers wrote that medical or social vulnerabilities, such as underlying medical conditions or employment in essential services, could raise Asian Americans' risk of death from COVID-19. Disparities in health care access and quality could also be contributing factors because of lower English proficiency rates and income, they added.
Nguyen said researchers are working on gathering data to more closely analyze whether the numbers indicate a problem.
He said data collection for Asian Americans tends to be weak. The group is sometimes lumped in with Pacific Islanders and other groups — which makes it difficult to uncover specific trends — while some states do not report Asian American COVID-19 data.
Download the NBC News app for full coverage and alerts about the coronavirus outbreak
Data compiled by the American Public Research Lab from 39 states and Washington, D.C., show that as of May 11, COVID-19 deaths among Asian Americans were generally proportional to their share of the population. However, a number of states count Asians in the "other" category, and it is unknown whether certain states that have reported zero Asian deaths also count them as "other."
The San Francisco researchers wrote that disaggregated data collection, better transparency and more research are needed to determine Asian Americans' risks and to help policymakers create a safe and phased-in reopening strategy.
"Understanding the reasons for disparities in COVID-19 incidence and mortality is critical for protecting all vulnerable communities through policies to address health disparities," they wrote.