With a mask mandate now in effect, we looked at why the CDC and California have different COVID-19 data – KSBW Monterey

On Friday, all Monterey County residents will be under a face-covering ordinance after the Centers for Disease Control and Prevention (CDC) listed the county as having a substantial level of COVID-19 community spread. In September, the Monterey County Board of Supervisors voted 3-2 to approve a final version of an indoor mask ordinance. The mask mandate was only triggered when the county’s COVID-19 transmission rate was considered high or substantial according to the CDC. Read the full ordinance here: Completed Board Order and Ordinance Item No. 19Read an FAQ provided from the county, here: What You Need to Know: Monterey County’s Face Covering OrdinanceThe ordinance requires everyone in the county to wear facial coverings indoors, regardless of vaccination status, with few exceptions.Since the ordinance was first passed, questions have been raised about the validity of the CDC data. When compared to the Monterey County Health Department’s and the California Department of Public Health’s (CDPH) data, the numbers were never lining up. COVID-19 Data Discrepancies On Friday morning, at the time of publication, CDPH reported Monterey County had 42 cases per 100,000 over the past week while the CDC reported 66 cases per 100,000. The CDPH would place the county in a lower CDC tier. In early September, the CDC reported that Monterey County had one of the lowest COVID-19 case rates in the country. The CDC’s website reported that over a seven-day period Monterey County had zero new cases and just a 3.81% positivity rate. It was later determined that the CDPH had a data error and had been reporting wrong data to the CDC causing the bad reporting. Once that reporting error was cleared up the data still didn’t match when looking at the CDC numbers versus the state and local data. On Wednesday, Nov. 4, two days before the mask ordinance was to be enforced, Monterey County held one of their weekly briefings with the press. The Zoom meeting has been held almost every Wednesday since the start of the pandemic. It’s a place where the press can have access to local officials and is regularly attended by Monterey County Health Officer, Dr. Edward Moreno. At the Nov. 4 meeting, the data discrepancy was a hot topic with a handful of questions focusing on the numbers. Moreno was asked if the CDC data, which shows a more grim situation, or the state’s data more accurately reflected the reality in Monterey County. Moreno explained that the CDC reports a weekly average with a three-day lag, while the state gives a daily average over a week with a seven-day lag. The lag in reporting partially explained the data differences. When asked about why there was a discrepancy between the state data and the CDC data Dr. Moreno said he couldn’t explain it. “Yeah, we don’t know how the CDC calculates their case rates for Monterey County,” said Moreno. Understanding the DataKSBW 8 reached out to the CDC to get an explanation for the difference in the numbers. “We were able to confirm that our numbers are accurate,” said Jade Fulce, Public Affairs Specialist with the CDC. Fulce went on to talk about their specific algorithm. A key part of their explanation was the fact that the CDC calculates the case rate using new cases by report date. The report date data means if there was a backlog and Monterey County was to report a thousand new cases in a day, the CDC would use that number in the calculations. This would not accurately portray the 7-day average since that data could be weeks or months old. “Report date is subject to variations in reporting,” explained the California Department of Public Health, Office of Communications, in response to a similar inquiry from KSBW 8. The CDPH responses added additional context to the CDC data. According to the CDPH, the CDC’s case count includes both confirmed and probable cases of COVID-19, while the state only includes confirmed cases.“A probable case or death is defined as any one of the following: Meets clinical criteria AND epidemiologic linkage with no confirmatory laboratory testing performed,” the CDC reports on their website. The added amount of probable cases is not easily broken down on the CDC’s website. In addition, a look at the data released by all three agencies shows that they are all using different population sizes when calculating their case rate per 100,000 people. The CDC estimates the county has 14,000 fewer people than what the county health department says. Using report date data, adding probable cases, and estimating a smaller population size are all factors into why the CDC data does not match up with local and state reporting and why the CDC is reporting a higher rate of COVID-19 spread than both agencies. Monterey County Supervisors The Monterey County Board of Supervisors was split on their support for the mask ordinance. With cases relatively low compared to several peaks of the pandemic and the county reporting 84% of residents 12 and older being vaccinated, the new rule seemed unnecessary to some. “As a Supervisor I have vowed to trust the data and science, our County has a team of Public Health Professionals, which include Dr’s and epidemiologists, that help us make these decisions. In this case Dr. Moreno and his team were not recommending the action the Board was considering,” wrote Supervisor Chris Lopez on Facebook after voting against the ordinance. Initially, the board attempted to pass the measure as an emergency order, which would have required four supervisors to support it. Only three voted in favor. “I look forward to bringing it back, again, for consideration when our rates inevitably rise,” said Supervisor Wendy Root Askew at a September Board of Supervisors meeting when the first attempt failed. A week later, the ordinance was brought to vote again, this time not as an urgency ordinance, meaning that the three supervisors in favor of the new rules would be able to pass it. KSBW 8 reached out to the Monterey County Supervisors who voted in favor of the mask ordinance to ask them about the data discrepancy. Questions emailed to their office asked them to explain the differences in the county and CDC data and if they knew how the CDC arrived at their numbers. “Our ordinance follows what the Bay Area health officers relied on for their indoor mask orders and that is the CDC’s transmission rate tiers,” wrote Supervisor Alejo. On the data, Alejo wrote, “I can’t speak for why the CDC data is different than the counties, only the CDC can do that. But public health officials across the country do rely on their transmission data for similar indoor mask orders.”Supervisor Askew did not respond for comment. Supervisor Adams was traveling and unable to be reached.

On Friday, all Monterey County residents will be under a face-covering ordinance after the Centers for Disease Control and Prevention (CDC) listed the county as having a substantial level of COVID-19 community spread.

In September, the Monterey County Board of Supervisors voted 3-2 to approve a final version of an indoor mask ordinance. The mask mandate was only triggered when the county’s COVID-19 transmission rate was considered high or substantial according to the CDC.

The ordinance requires everyone in the county to wear facial coverings indoors, regardless of vaccination status, with few exceptions.

Since the ordinance was first passed, questions have been raised about the validity of the CDC data. When compared to the Monterey County Health Department’s and the California Department of Public Health’s (CDPH) data, the numbers were never lining up.

COVID-19 Data Discrepancies

On Friday morning, at the time of publication, CDPH reported Monterey County had 42 cases per 100,000 over the past week while the CDC reported 66 cases per 100,000. The CDPH would place the county in a lower CDC tier.

In early September, the CDC reported that Monterey County had one of the lowest COVID-19 case rates in the country. The CDC’s website reported that over a seven-day period Monterey County had zero new cases and just a 3.81% positivity rate. It was later determined that the CDPH had a data error and had been reporting wrong data to the CDC causing the bad reporting.

Once that reporting error was cleared up the data still didn’t match when looking at the CDC numbers versus the state and local data.

On Wednesday, Nov. 4, two days before the mask ordinance was to be enforced, Monterey County held one of their weekly briefings with the press. The Zoom meeting has been held almost every Wednesday since the start of the pandemic. It’s a place where the press can have access to local officials and is regularly attended by Monterey County Health Officer, Dr. Edward Moreno.

At the Nov. 4 meeting, the data discrepancy was a hot topic with a handful of questions focusing on the numbers. Moreno was asked if the CDC data, which shows a more grim situation, or the state’s data more accurately reflected the reality in Monterey County. Moreno explained that the CDC reports a weekly average with a three-day lag, while the state gives a daily average over a week with a seven-day lag.

The lag in reporting partially explained the data differences.

When asked about why there was a discrepancy between the state data and the CDC data Dr. Moreno said he couldn’t explain it.

“Yeah, we don’t know how the CDC calculates their case rates for Monterey County,” said Moreno.

Understanding the Data

KSBW 8 reached out to the CDC to get an explanation for the difference in the numbers.

“We were able to confirm that our numbers are accurate,” said Jade Fulce, Public Affairs Specialist with the CDC.

Fulce went on to talk about their specific algorithm. A key part of their explanation was the fact that the CDC calculates the case rate using new cases by report date. The report date data means if there was a backlog and Monterey County was to report a thousand new cases in a day, the CDC would use that number in the calculations. This would not accurately portray the 7-day average since that data could be weeks or months old.

“Report date is subject to variations in reporting,” explained the California Department of Public Health, Office of Communications, in response to a similar inquiry from KSBW 8.

The CDPH responses added additional context to the CDC data.

According to the CDPH, the CDC’s case count includes both confirmed and probable cases of COVID-19, while the state only includes confirmed cases.

“A probable case or death is defined as any one of the following: Meets clinical criteria AND epidemiologic linkage with no confirmatory laboratory testing performed,” the CDC reports on their website. The added amount of probable cases is not easily broken down on the CDC’s website.

In addition, a look at the data released by all three agencies shows that they are all using different population sizes when calculating their case rate per 100,000 people. The CDC estimates the county has 14,000 fewer people than what the county health department says.

Using report date data, adding probable cases, and estimating a smaller population size are all factors into why the CDC data does not match up with local and state reporting and why the CDC is reporting a higher rate of COVID-19 spread than both agencies.

Monterey County Supervisors

The Monterey County Board of Supervisors was split on their support for the mask ordinance. With cases relatively low compared to several peaks of the pandemic and the county reporting 84% of residents 12 and older being vaccinated, the new rule seemed unnecessary to some.

“As a Supervisor I have vowed to trust the data and science, our County has a team of Public Health Professionals, which include Dr’s and epidemiologists, that help us make these decisions. In this case Dr. Moreno and his team were not recommending the action the Board was considering,” wrote Supervisor Chris Lopez on Facebook after voting against the ordinance.

Initially, the board attempted to pass the measure as an emergency order, which would have required four supervisors to support it. Only three voted in favor.

“I look forward to bringing it back, again, for consideration when our rates inevitably rise,” said Supervisor Wendy Root Askew at a September Board of Supervisors meeting when the first attempt failed.

A week later, the ordinance was brought to vote again, this time not as an urgency ordinance, meaning that the three supervisors in favor of the new rules would be able to pass it.

KSBW 8 reached out to the Monterey County Supervisors who voted in favor of the mask ordinance to ask them about the data discrepancy. Questions emailed to their office asked them to explain the differences in the county and CDC data and if they knew how the CDC arrived at their numbers.

“Our ordinance follows what the Bay Area health officers relied on for their indoor mask orders and that is the CDC’s transmission rate tiers,” wrote Supervisor Alejo.

On the data, Alejo wrote, “I can’t speak for why the CDC data is different than the counties, only the CDC can do that. But public health officials across the country do rely on their transmission data for similar indoor mask orders.”

Supervisor Askew did not respond for comment. Supervisor Adams was traveling and unable to be reached.