Do not be skeptical of COVID-19 threat

With the COVID-19 pandemic firmly established in the United States and taking hold in Minnesota, there are several things that can and should be done now to prepare for events in the coming weeks and months and to reduce their impact on the physical, mental and financial health of the state and the nation.

As of 11 a.m. Central time on March 16, there were at least 3,823 confirmed cases and 67 deaths in the United States. In Minnesota, as of Monday afternoon, there were 54 active cases and fortunately no deaths.

Most early models suggest the COVID-19 pandemic will get much worse before it gets better. Early projections from the Centers for Disease Control and Prevention (CDC) regarding the potential toll of COVID-19 in terms of total number of infections, hospitalizations and deaths are striking in the worst-case scenarios where little is done at the population level to slow disease transmission. Between 160 million and 240 million people could be infected and between 200,000 and 1.7 million could die (a really bad year of seasonal flu kills approximately 60,000 and the 2009 H1N1 pandemic flu killed about 13,000).

The good news is that quick action and preparedness can dramatically slow the spread of COVID-19 and reduce the number of infections. Strong evidence already exists showing well-prepared countries that act quickly to control spread see far fewer cases of COVID-19 and correspondingly realize far fewer deaths. Singapore and Hong Kong are model examples of how comprehensive public health measures save lives. Even in China, where the pandemic began, comprehensive public health measures in all non-Hubei provinces produced a stark difference in the number of infections (67,790 in Hubei province vs. 13,186 in the rest of China). More important, because transmission was controlled in non-Hubei provinces, the early evidence is that COVID-19 mortality rates will be far lower outside of Hubei. As of Sunday, there were 3,193 COVID-19 deaths in China, and 3,075 of those were in Hubei province, which accounts for 4% of China's population — that is, 95% of deaths so far in China have occurred among 4% of the population, and this is almost entirely due to public health efforts to slow transmission outside of Hubei.

The concept of slowing transmission is frequently described as "flattening the curve," which refers to minimizing the upper limit of infections that develop and spreading them out over time, as nicely described in a recent article.

Despite clear evidence that COVID-19 is here to stay for the foreseeable future, and strong evidence that quick public health action centered around COVID-19 testing and social distancing can dramatically reduce the impact of COVID-19, skepticism remains among some members of our communities as to the seriousness of the threat. Some question the value of social distancing and worry that the toll on the economy is of greater concern than the toll on human health and loss of life. This opinion is often based on early data suggesting that about 80% of cases are mild and that children appear to be minimally affected.

While these data offer optimism, the numbers should not lead to complacency, for at least two key reasons. First, broad transmission will result in significant premature loss of life among people with pre-existing conditions (e.g., diabetes, cardiovascular disease and otherwise compromised immune systems) and the elderly, because infected individuals with mild symptoms will propagate transmission despite low risk to themselves. Second, the threat of COVID-19 is not just the infection itself but the indirect threat it poses even to vulnerable populations who never get infected. This is because of the potential for this pandemic to overwhelm the health care system. We now turn our focus to this threat, what is being done to prepare and how communities can aid in the effort.

Reducing the burden of COVID-19 on the health care system is of paramount importance. This plays out via many possible scenarios, but the most obvious is the threat of overwhelming hospitals, which not only will reduce our ability to contain COVID-19 but also will greatly impact the delivery of essential clinical care for non-COVID-19 conditions — particularly, chronic conditions including coronary heart disease, heart failure, stroke and diabetes.

Consider the example of heart attacks. In the U.S., a heart attack occurs every 40 seconds, culminating in 805,000 heart attacks annually. These events will not stop during the COVID-19 pandemic, and there is good reason to believe they may actually accelerate, since several studies have shown that infections similar to COVID-19 can trigger cardiovascular events. In an overwhelmed system, treating these emergency medical conditions becomes challenging. As alluded to above, the best approach to minimizing burden on the health care system is to slow the spread of disease ("flattening the curve"). The goal is not only to reduce the number of total infections but, as important, to reduce the number of active infections at any moment. When large numbers of infections begin to occur on a daily basis and this is sustained, clinics and hospitals quickly become overwhelmed and the system grinds to a halt.

In a hospital, the mission is to care for the sickest patients with life-threatening illnesses or debilitating injuries that will only worsen at home. The coronavirus doesn't change that mission, but it does change the way that we have to think about delivering care.

Fortunately, this change in thinking about the way health care professionals do their work is something that we're prepared for in Minnesota. Facilities across the entire health care system have had detailed pandemic plans in place for years. As you read this, health care leaders from all over the country continue to work off these plans and adapt them to plan for the coronavirus. Consider some of the following potential problems for which we have contingency plans:

If a suspected COVID-19 case is seen in standard clinical examination room, that room, in most hospitals, could require one hour of isolation to allow for disinfection as well as adequate air circulation to clear any airborne virus. The same concept holds for computed tomography machines used to diagnose pneumonia — a life-threatening sequelae of COVID-19. Whenever a COVID-19 patient receives a CT scan, the machine is unavailable for an hour, rendering it unavailable to a patient with a stroke who would urgently require a CT to inform the diagnosis and make lifesaving treatment decisions. To address this, plans are underway to enable drive-through testing that does not require individuals to get out of their car, thereby keeping examination rooms available for patients without suspected COVID-19, while also minimizing exposure to other patients and health care professionals. Additionally, many doctors across the state can perform virtual visits, which are conducted via a smartphone or tablet from your home, minimizing the burden on hospitals.

This eventuality will reduce capacity to treat patients. The ultimate goal is prevention, and we have established protocols, guided by the CDC and Minnesota Department of Health, regarding personal protective equipment (PPE), including when to use gloves, surgical gowns, surgical masks, face shields and respirators. In preparation for infection of health care workers, some hospitals are trying to identify temporary housing for these individuals while they recover, to reduce family transmission. Following recovery, we expect them to become incredibly valuable, since they will likely have immunity going forward.

A small percentage of COVID-19 patients require mechanical ventilation to support recovery. If hospitals run out of their usual supply of ventilators, many will have additional supply in operating rooms, and one contingency plan for a typical hospital would be to reserve one for emergency surgeries and use the others to care for more patients than we usually could.

We have isolation plans to keep COVID-19 patients separate from uninfected patients. Many hospitals have negative-pressure ventilation systems designed to prevent airborne transmission of disease. Additionally, hospital use of PPE describe above will also help to minimize spread of infection within the hospital setting.

It is critically important to realize that these preparations for COVID-19 will only have success if we flatten the curve so the system is only mildly stressed, rather than completely overwhelmed. If we assume that 10% of COVID-19 cases are hospitalized (in China it was about 15%) and we limit infections to only 10 million, that would require 1 million hospital beds for COVID-19 patients during the course of the pandemic; if these cases accrue slowly over many months, the system has a better chance to manage this high demand using the approximately 925,000 hospital beds in the United States. Alternatively, if cases develop rapidly or the total number of cases surges to 60 million (the number infected with pandemic H1N1 influenza in 2009), that translates into 6 million hospitalizations and likely overwhelms the system, causing a breakdown in health care provision with significant ripple effects. Imagine patients with heart attacks or severe trauma from car accidents or falls who cannot receive lifesaving medical care because there aren't enough ventilators, hospital beds or health care workers to meet the demand. Unintended consequences of this nature are already reported to be occurring in Italy due to an overwhelmed system.

1. Minimize social contact if you're healthy — rapid efforts for social distancing will be important for slowing the spread and "flattening the curve."

2. Wash your hands. Soap and water are sufficient or hand sanitizers with at least 60% alcohol.

3. Ensure supplies of necessary items to have at home, including prescription medicines (check your refill dates) and nonprescription medications such as fever-reducing medications. The goal is to be prepared, but don't hoard.

4. Stay home if you are sick and don't go to the doctor's office with mild symptoms (after all, most people with COVID-19 have mild symptoms and recover). Call first to receive advice about how and if to see a health care professional.

5. Don't demand a test. Health professionals are working to determine best testing practices until testing is scaled up nationally. In most situations, the test result won't change the treatment if symptoms are mild.

6 For up-to-date, science and practical advice on the pandemic, use the following resources:

• Center for Infectious Disease Research and Policy at the University of Minnesota's School of Public Health (www.cidrap.umn.edu).

• The Minnesota Department of Health: (www.health.state.mn.us/#coronavirus).

• The U.S. Centers for Disease Control and Prevention: (www.cdc.gov/coronavirus/2019-ncov/index.html).

In summary, the message is not to be fearful but to be proactive and vigilant. Our public health and medical professionals have been planning for an event of this nature, but in order for plans to be effective, it is the responsibility of everyone to be good citizens, heed advice from public health officials and do our best to slow the initial spread of the virus. The time is now.

Dr. Ryan Demmer is an associate professor of epidemiology in the University of Minnesota's School of Public Health. Dr. Bob Mullaney is a family medicine physician and is a member of a COVID-19 preparedness team.