Tier roller-coaster continues in San Diego County

The roller-coaster continues in San Diego County with the latest set of coronavirus numbers showing that the region’s closely-watched case rate is once again over the state-specified limit that governs the region’s ability to keep restaurants and other organizations open at their present capacities.

According to the data available Monday, there were 1,704 confirmed coronavirus cases recorded from Sept. 13 through Sept. 19, the period the state will use to calculate the region’s case rate per 100,000 residents in a statewide report published every Tuesday.

The total number of cases recorded in the seven-day window is about 50 greater than the limit necessary to stay at or under seven cases per 100,000 residents. Anything higher than 7 qualifies the region for the more restrictive “purple” tier of the state system, but only if scores are over the threshold for two consecutive weeks, meaning that San Diego County would need another over 7 score in next week’s report to fall a tier.

If that happened, as it almost did last week, restaurants, churches, gyms and other organizations now allowed to use some of their indoor operating spaces, would be mandated to move back outdoors. Whether that would actually happen is anyone’s guess.

Some members of county boards of supervisors, backed by a large number of business owners fed up with the up-and-down nature of the system’s COVID-19 risk reduction strategy, have said they simply won’t comply with any effort to move back outdoors again.

The issue is virtually guaranteed to come up once again during the local public health department’s biweekly report to the San Diego County Board of Supervisors Tuesday.

Meanwhile, the latest daily coronavirus numbers looked under control Monday with 124 new cases announced. One COVID-related death was announced.

It is not certain whether San Diego County will post a case rate in Tuesday’s report that points toward the purple zone.

While the raw case rate, based on 1,704 cases in the state’s calculation window and a local population of more than 3.3 million, yields a rate of 7.2 — 0.2 cases over the limit — that is not necessarily the number that will appear in Tuesday’s report.

The state adjusts raw case rate scores based on whether health providers in each county cumulatively performed more or less testing during the seven-day window than the median rate statewide.

Last week, San Diego County saw its raw rate of 6.8 cases per 100,000 adjusted upward to 6.9 based on a score of 210.5 tests performed per 100,000 residents during the previous seven-day window. That’s slightly less than the state median of 216.3. County officials said that the state’s last-minute exclusion of more than 1,000 tests of San Diego State University students caused the upward adjustment.

County supervisors directed local public health officials to work over the last week to make sure that all tests performed in the region were included in the upcoming report. Given that UC San Diego has recently begun testing thousands of students returning to campus, and SDSU has continued testing its own students, faculty and staff regularly, it is possible that the local testing rate is now over the state median, putting the region in line to see its raw case adjusted downward, rather than upward.

According to the state’s reopening blueprint, the number of tests per 100,000 performed locally from Sept. 13 through Sept. 19 would need to be less than 25 percent greater than the state median of 216.3 in order to reduce the case rate to 7 or less.

Tests fall inside or outside the seven-day window based on their “sample collection dates” — the day that each test subject turned up to have her or his nose swabbed. Neither the state nor the county publish the number of tests by sample-collection date, so it is difficult for the public to do the math before Tuesday’s report appears.

A county official said in a very brief email Monday that an adjustment is expected, but declined to specify whether the direction will be up or down.