COVID-19 cases are once again on the rise in Los Angeles County. Data from the Centers for Disease Control and Prevention show cases and hospitalizations trending upward since early summer.

Los Angeles County tracks COVID-19 case rates over time and by community. The Department of Public Health’s map shows the neighborhoods with the highest case rates as:

  • The Saugus neighborhood of Santa Clarita
  • City of Vernon
  • Unincorporated area neighboring Whittier Narrows south of El Monte
  • City of Industry

Only those four communities designated on the county’s map are in the second-highest category for COVID case rates, according to the latest data. However, there are dozens of neighborhoods in the next-highest category. That includes large swaths of L.A. County, especially the areas around Lancaster and Palmdale; the Valley including North Hollywood, Van Nuys and Northridge; most of South and East Los Angeles; and parts of east L.A. County including Pomona and Covina.

The data on the county’s map reflects a 14-day rolling average, which can help even out swings in day-to-day reporting. The case rate are per 100,000 residents, which makes it easier to compare prevalence of the virus between highly populated areas and less dense areas.

The cases are reported on a lag, and only reflect reporting up to July 1. The data also doesn’t include the cities of Long Beach and Pasadena.

Aside from those limitations, there’s another challenge in understanding the full scope of coronavirus spread in Los Angeles County: It’s not clear how many people may be testing positive at home.

If you take a COVID-19 test at a testing site, those results are reported to the Department of Public Health. However, if you take an at-home rapid test, those results aren’t tracked anywhere — unless you take the extra steps to report it.

The Centers for Disease Control and Prevention recommends people who test positive at home report the case to their healthcare provider, who can pass that information on to the proper databases. Your doctor will also be able to recommend treatments based on your symptoms.