ARIZONA — Arizona’s COVID-19 cases have continued to rise, but we won’t know for several weeks how last week’s partial reopening will affect the trend.
Charts showing a steady rise in both deaths and confirmed cases have stoked skepticism by health experts and the public alike as host of businesses have moved cautiously to reopen and weekend crowds have again thronged Arizona’s high country.
One team of epidemiologists from the state’s universities working with the state developed models of future infections, with models suggesting any major reopening before the end of May would likely result in a big surge in infections. Prior to making the decision to start a phased reopening on May 15, the state told the scientists to stop working on the models and cut off access to state tracking data. The state has since somewhat modified that decision, according to articles in the Arizona Republic.
The state is instead relying on a model approved by the Federal Emergency Management Agency (FEMA), although it has declined to release the results of that model.
Some 23 researchers from the University of Arizona and Arizona State University developed the model that predicted another two-week delay in reopening would reduce the odds a fresh surge in cases.
Recent testing shows that people of all ages get infected at about the same rate, but the death rate is far higher among those over 55 and those with health risks like heart disease, diabetes, obesity and lung disease. Some 80 percent of the deaths in Arizona are among people older than 65.
Studies suggest that the infection rate is only about 11 percent for people actually living together – although in some cases whole families have gotten infected. Most studies suggest a relatively low rate of infection in the outdoors or through casual contact, although the existence of “super spreaders” remains poorly understood.
The statistics regularly updated on the state health departments’ website offer mixed signals. The state’s hospitals still have plenty of empty beds, although the number of hospitalized COVID-19 patients remains steady. Moreover, the percentage of swab tests coming back positive has declined from about 10 percent to about 5 percent. In “cool spots” like Gila County only about 2 percent of the tests are coming back positive. However, in “hot spots” like Navajo and Apache counties some 20 percent of the swab tests have come back positive.
Those encouraging signs could mostly reflect the big increase in testing – especially in lower-risk groups without symptoms.
On the other hand, overall cases increased 25 percent and deaths by 39 percent in the week prior to lifting the stay-at-home order. On May 8, the state had reported 426 deaths. This Monday, the total stood at 686. Deaths are considered a more reliable way to track the course of the pandemic, given the big variations in testing.
Arizona had the lowest per-capita testing rate in the nation prior to the launch of weekend testing blitz two weeks ago. The blitz aimed to perform 10,000 to 20,000 tests, with nine test centers throughout the country – including one at Summit Healthcare in Show Low.
In Gila County, the MHA Foundation joined forces with the Gila County Health Department and the CERT emergency response teams to set up a testing site on their own.
However, Navajo and Apache Counties remain among the most hard hit areas in the country, with still-rising per capita infection and death rates – many concentrated on the Navajo Reservation. Another cluster of cases has started to emerge on the White Mountain Apache reservation.
The effect of the opening won’t show up for several weeks, given the time between infection and the onset of symptoms. Even then, studies suggest half the people infected will show few or no symptoms – although they can still spread the disease. Nationally, most of the cases have emerged in nursing homes or in family clusters.
Overall, Arizona has lagged somewhat behind the national trends when it comes to bending the curve downward, with total cases and deaths very slowly declining. The US has the worst outbreak in the world, with more than 1.4 million confirmed cases and 90,000 deaths. Nationally, the rolling, seven-day average of new cases has been declining very slowly since peaking in mid-April. The death toll has also declined steadily, although it remains above 1,000 daily.
However, instead of slowly declining, Arizona cases and deaths continue to slowly increase, with more than 14,000 cases and 700 deaths. The Arizona statistics have been confused by long lags in reporting deaths. The state’s website adds deaths to the statistics when they’re reported, not when they took place. That has made it harder to determine the trend over time. Deaths may have peaked in early May with a one-day spike of 67, but that’s unclear due to the lag in reporting. State officials say the one-day spike included many deaths that took place earlier. The true one-day spike prior to that anomaly was 22 on both April 19 and April 20. However, on May 7 the state reported 19 deaths and on May 8 another 21, suggesting the trend in deaths remains on a plateau rather than declining.
The toll remains overwhelmingly concentrated among the elderly, with 80 percent of the deaths so far among those over 65 and another 11 percent among those between 55 and 65. Native Americans have three times the death rate as whites. A dismaying one third of the deaths have taken place among nursing home residents, with other clusters of cases in prisons and jails.
Statewide, 1 in 522 people have become infected and 1 in 10,704 have died. But in Navajo County, 1 in 85 have been infected and 1 in 2,265 have died. In Apache County, 1 in 73 have gotten infected and 1 in 3,576 have died. The only county that’s close to that grim toll is Coconino County, with 1 in 162 infected and 1 in 2,191 dying.
The computer models of infections have generated a wide range of predictions throughout the pandemic, both nationally and locally. The success of social distancing has a big impact on the predictions – which is a constantly moving target.
The state has mostly relied on a FEMA approved model developed by Johns Hopkins University, although state officials have not released the detailed projections.
A University of Texas model has generated an 80 percent chance that the state has already passed the peak of infections.
A second IHME model also suggest the state has passed the peak of infections.
On the other hand University of Arizona professor Joe Gerald said infections have continued to rise based on cases contracted prior to any easing in the social isolation guidelines.
A model developed by researchers from MIT suggests Arizona’s cases will continue to rise for the next month.
The situation remains equally murky nationally, although new cases and deaths have more clearly begun to decline – albeit slowly. Some of the worst hit areas hit a deadly peak and have now reported steep declines in new cases – like New York City. Some states quick to reopen like Georgia have yet to show any uptick in cases. Others like Texas have seen a surge – although many of those cases may have come before the reopening.
A national database published by the New York Times lists 19 states with a clear decrease in new cases, mostly East Coast states that had a much more severe, early outbreak than Arizona. Three states are still experiencing a clear increase.
Arizona falls into the middle group of 29 states where cases have may have declined from the peak, but now remain on a plateau.
In the past week, the nation has averaged 20,000 new confirmed cases and 1,000 deaths daily.
Even the experts aren’t sure how those numbers will change in the next several weeks, now that two-thirds of the states have at least partially reopened their economies. One study based on cell phone data found that in late April 44 percent of the nation’s residents did not leave their homes for the week. The infections now showing up in the official figures reflect new infections in roughly that period. The deaths probably reflect infections contracted in early April – since the average patient who dies got infected a four to six weeks before their death, according to studies.