Backlog of data causes McHenry County’s positivity rate to spike

This illustration, created at the Centers for Disease Control and Prevention (CDC), reveals ultrastructural morphology exhibited by coronaviruses

The level of COVID-19 transmission in McHenry County remained high Monday, the McHenry County Department of Health reported.

The McHenry County health department reported 1,473 new cases of COVID-19 on Monday but no additional deaths. That brings the total to 64,274, including 377 deaths and 36 deaths that likely were caused by COVID-19 but have not been confirmed.

The county has recorded two COVID-19 deaths so far in 2022.

The test positivity rate for the county, as measured by a seven-day rolling average, spiked to 35.7% Friday because of a backlog of data from a lab that had not yet been included in the state’s reporting, according to the Illinois Department of Public Health.

The data was updated on Friday and Saturday, but it contained cases dating back to Dec. 23, IDPH spokeswoman Melaney Arnold said.

“IDPH is working with this lab to prevent future backlogs and apparent artificial spikes in cases,” Arnold said in an email.

The region including both Lake and McHenry counties saw its test positivity rate increase Friday to 21.3%.

McHenry County’s incidence rate fell to 1,083.47 new cases over seven days per 100,000 residents as of Wednesday, the last day for which data was reported, according to the McHenry County health department.

That is below the peak on Jan. 9, which was the highest the county had seen over the previous 250 days, the time period published by the county, but remains more than 10 times the threshold set by the Centers for Disease Control and Prevention to indicate a high level of transmission within a community.

For transmission risk to meet the less severe category “substantial,” the incidence rate would need to fall below 100 new cases over seven days per 100,000 residents, and the positivity rate would need to be below 10%, according to the McHenry County health department. Both metrics then would need to stay below those levels for a week.

COVID-19 hospitalizations fell for the eighth straight day across Lake and McHenry counties, the Illinois Department of Public Health reported Monday.

The number of people hospitalized with COVID-19 in McHenry and Lake counties decreased to 331 Sunday after a high for the pandemic of 407 on Jan. 15, the IDPH reported.

Hospitalizations, measured by a seven-day rolling average, decreased nine of the past 10 days in the two-county region, state data shows. It had been increasing every day since Dec. 26 before Jan. 14.

Hospital intensive care unit availability across McHenry and Lake counties remained at 14% Monday. It has been below the 20% threshold previously used by the state as a trigger point for imposing stricter health mitigations since Dec. 28.

In McHenry County alone, 4.8% of medical and surgical hospital beds remain available on average, according to the seven-day rolling mean reported Monday by the McHenry County health department. An average of 15.7% of ICU beds were available.

Hospitalizations for COVID-19-like illness decreased nine of the past 10 days in the county as of Monday.

Statewide, the number of hospitalizations tied to COVID-19 decreased Sunday to 5,238, the IDPH reported. Of those hospitalized, 905 patients were in the ICU and 541 were on ventilators.

An additional 2,323 COVID-19 vaccine doses were administered to McHenry County residents since Friday’s report, according to the IDPH, bringing the total number administered locally to 487,854. The state reported that 92,796 booster shots were administered in McHenry County.

A total of 193,221 county residents, or an estimated 62.62% of McHenry County’s population, now are fully vaccinated, meaning they’ve received all doses recommended for the vaccine they were given.

Statewide, 20,305,950 vaccines have been administered, according to state data.

Across Illinois, 79.5% of those age 5 and older have received at least one dose of a vaccine against COVID-19, and 69.8% are fully vaccinated, the IDPH reported Monday. Those rates are 83.7% and 74.1% for those age 12 and older, 85.2% and 75.4% for people 18 and older, and 95% and 87.1% for those 65 and older, respectively.

Statewide, the IDPH tallied 64,499 total new cases of COVID-19 on Monday. Another 310 deaths also were logged, bringing the totals to 2,837,861 cases, 30,155 confirmed deaths and 3,648 probable deaths.

Neighboring Lake County’s health department reported a total of 110,862 cases and 1,206 deaths through Friday. To the south, Kane County’s health department reported 114,402 cases and 1,000 deaths as of Friday.

Among McHenry County ZIP codes, Crystal Lake (60014) has the highest number of COVID-19 cases with a total of 10,196 confirmed, according to county data. McHenry (60050) follows with 7,428.

The McHenry County health department reports ZIP code data only for parts within McHenry County, a department spokeswoman said. Any discrepancies between county and IDPH numbers likely are because of the data’s provisional nature and because each health department finalizes its data at different times, she said.

The following is the rest of the local breakdown of cases by ZIP code: Woodstock (60098) 6,951 cases; Lake in the Hills (60156) 5,912; Huntley (60142) 4,926; Cary (60013) 4,874; Algonquin (60102) 4,471; Johnsburg and McHenry (60051) 4,150; Harvard (60033) 3,029; Marengo (60152) 2,429; Wonder Lake (60097) 2,381; Crystal Lake, Bull Valley and Prairie Grove (60012) 2,247; Spring Grove (60081) 1,358; Fox River Grove (60021) 936; Island Lake (60042) 861; Richmond (60071) 630; Hebron (60034) 361; Barrington (60010) 274; Union (60180) 254; and Ringwood and Wonder Lake (60072) 167.

Have a Question about this article?