A California emergency department research collaboration

310 EDs. One statewide goal.

A growing amount of all care in California is being provided in our state’s emergency departments. This includes HIV testing. But no data source shows how many HIV tests each ED performs, or how many of those tests find HIV. Help us build the first statewide, ED-based dataset on HIV testing.

1of 310 California EDs contributing · 1 of 58 counties
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California’s emergency departments

310 emergency departments across 55 of the state’s 58 counties, shaded by how many each county has.

San Benito County: 1 EDShasta County: 3 EDsSierra County: 0 EDsFresno County: 6 EDsAmador County: 1 EDEl Dorado County: 2 EDsMonterey County: 4 EDsSan Bernardino County: 18 EDsTehama County: 1 EDNevada County: 2 EDsTuolumne County: 1 EDSanta Barbara County: 5 EDsTrinity County: 1 EDStanislaus County: 4 EDsColusa County: 1 EDAlpine County: 0 EDsSiskiyou County: 2 EDsDel Norte County: 1 EDInyo County: 2 EDsSan Joaquin County: 7 EDsImperial County: 2 EDsCalaveras County: 1 EDButte County: 3 EDsMadera County: 1 EDVentura County: 7 EDsOrange County: 24 EDsKern County: 8 EDsContra Costa County: 7 EDsKings County: 1 EDMendocino County: 3 EDsSonoma County: 6 EDsYuba County: 1 EDMerced County: 2 EDsTulare County: 3 EDsSacramento County: 8 EDsSolano County: 4 EDsSan Francisco County: 9 EDsMariposa County: 1 EDMarin County: 3 EDsSutter County: 0 EDsLassen County: 1 EDRiverside County: 16 EDsPlumas County: 3 EDsPlacer County: 3 EDsSan Luis Obispo County: 4 EDsSan Mateo County: 6 EDsMono County: 1 EDSan Diego County: 15 EDsNapa County: 2 EDsAlameda County: 12 EDsYolo County: 2 EDsLake County: 2 EDsLos Angeles County: 70 EDsGlenn County: 1 EDSanta Cruz County: 2 EDsHumboldt County: 4 EDsModoc County: 1 EDSanta Clara County: 9 EDsLos Angeles
EDs per county:None12–34–910–2470

California’s EDs are spread unevenly across the state: Los Angeles County alone has 70, while three counties have none. Many of these EDs serve as the front, and often only, door to care for Californians without insurance or stable housing. The state has begun to invest in ED screening; in 2023, California funded 28 EDs to screen for HIV, syphilis, and hepatitis C, and it has set aside $60 million more under SB 164.

Collaborating institutions include:

Stanford Medicine

This work is supported by the National Institute of Allergy and Infectious Diseases (NIAID) K08AI181642. Work and opinions here are those of the study team. They should not be construed to represent views of either the NIH or NIAID.