If worse comes to worst, Knox County's pandemic response calls for school bus drivers to take over as ambulance personnel gets sick, cites a likely sharp increase in need for hospital ventilators and emphasizes social distancing measures would save lives.

The plan, obtained through an open records request, is based on a pandemic as severe as the 1918 Spanish flu outbreak. A Knox County Health Department spokesperson said the plan was undergoing updates in response to specific threats from COVID-19.  

The department's director, Dr. Martha Buchanan, stressed Tuesday the risk to most people in East Tennessee is low. 

"Right now, that positive number is one. One isolated case," Buchanan said emphatically. "I anticipate that will change, but right now we stand at one and I want to give that context to our community."

After Buchanan's comments Tuesday, the state Health Department reported a second case of COVID-19 for a person with a Knox County address. 

The person, however, does not actually live in Knox County, according to Buchanan. They live outside the United States and took the test in a different state, a place with "ongoing community transmission." 

The state tracks and reports cases based on a person's address, Buchanan said.

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The established response plan is for a severe pandemic, but similarities to the coronavirus are clear. The response plans for a novel influenza virus that circumvents normal immune defenses, spreads through respiratory droplets, is more deadly than seasonal flu and hits elderly populations the hardest. 

In such a scenario, hospitals may be overwhelmed, demand for ventilators may increase by 25 percent or more and medical staff may face up to 40 percent absenteeism due to the illness, the document said. 

"During a pandemic, demand will greatly exceed supply of certain medical resources such as hospital beds, mechanical ventilators, vaccines and antivirals," the plan reads. "It will be necessary to allocate scarce resources in ways that can save as many lives as possible.'

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In the event AMR, the county's primary ambulance provider, cannot meet staffing needs, "The Knox County School Bus Drivers Association has agreed to assist, by supplying drivers who are familiar with Knox County, since schools will be closed," the plan states. 

In such a scenario, drivers will report to AMR headquarters for orientation. 

County health leaders are already asking neighbors to practice "social distancing," a method of slowing virus spread by limiting contact with others with the goal of reducing sharp spikes in daily cases.

The plan outlines how important such strategies are in Knox County. 

"Social distancing measures will play a central role in minimizing illness and deaths in Tennessee," the plan states. "Sharply increasing case counts exacerbate the strain on the healthcare system, further reducing the resources available to seriously ill patients and increasing the likelihood of poor outcomes." 

"I do anticipate us getting to the level of community spread," Buchanan said Tuesday, referring to a wider infection rate than currently confirmed, "but we can slow that down doing some social distancing."

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The county plan notes that the effectiveness of social distancing is not known with certainty -- in part because leaders are not sure the public will comply enough to make distancing successful. 

"Implementation of social distancing strategies in Knox County may create social disruption and significant, long-term economic impacts," the plan said. "It is unknown how the public will respond to these measures." 

The county's response plans for possible waves of virus, with deadly outbreaks occurring for years. 

"There will be two to three 'waves' (local epidemics) of pandemic disease in most communities," one point marked "assumptions" reads. "The entire pandemic period (all waves) will last about two years before the virus becomes a routine seasonal influenza strain." 

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At a press briefing Tuesday, Buchanan said it is currently unclear whether COVID-19 will follow a similar pattern. 

"Right now what we know is that the cases in China are going down, are they going to go back up again? We don't know until we see that," she said.