Global health expert answers questions about the record number of COVID-19 cases in South Carolina

Melissa Varner
June 16, 2020
Illustration of a crowd wearing masks

Six weeks after lifting stay-at-home orders, South Carolina is seeing a record number of new coronavirus cases. As of Sunday, the South Carolina Department of Health and Environmental Control (DHEC) announced 799 new COVID-19 cases – a new record for the number of COVID-19 cases reported in a single day. This brings the total number of people confirmed to have COVID-19 in South Carolina to 18,795 and those who have died to 600.

Michael Sweat, Ph.D. director of the Center for Global Health at the Medical University of South Carolina, studies these numbers as the leader of the MUSC COVID-19 Epidemiology Intelligence Project team. The project was developed to analyze trends, provide timely and accurate information to government and business leaders, and to help hospitals and clinics get ready for COVID-19 patients.

Sweat recently answered questions about the rapid growth of new cases in South Carolina and shared his perspective on some confusing COVID headlines, such as the World Health Organization(WHO) clarifying its comments on how the virus spreads.

Why are COVID-19 cases rising in South Carolina?

The primary reason there has been a recent increase in COVID-19 cases is that people are now interacting with others more. In the middle of March, we saw extremely high growth of confirmed COVID-19 infections occurring. Several weeks later, state-wide business closures and stay-at-home orders were implemented, and within weeks the rate of new infections rapidly decreased. These lockdowns were profoundly effective. The lockdown orders started to be lifted in early May, and now that several weeks have passed, we are seeing the reverse effect of lockdowns, with increasing rates of infection. But society has not gone back to the same lifestyle as prior to the introduction of COVID-19. Many people, but not all, continue to work at home, socially distance, wear masks, and practice enhanced hand hygiene. Thus, the big questions now are how large an increase in infections will we see in the weeks ahead, and how much behavioral risk reduction is enough to keep the epidemic manageable?

How do we know the rise in cases isn’t because of an increase in testing?

It can be hard at times to differentiate between actual increases in the number of new COVID-19 cases, versus there being more people getting tested. However, this would be most likely to happen when there are significant numbers of people who cannot access testing and then testing becomes more available. Access to testing in South Carolina has improved substantially over time, and over the past six to eight weeks has been quite good. Moreover, based on reports from DHEC the number of tests conducted in the state has been very stable over the past six weeks. All these factors strongly suggest that the increases being seen are not from increased testing, but rather from increased transmission.

Have we reached the second anticipated peak of coronavirus cases in South Carolina?

It’s probably useful to think of what is happening with the COVID-19 epidemic in the state as a series of micro-epidemics. In many geographic areas there is definitely a second peak developing. For example, in Charleston in early April there was a peak number of approximately 380 active COVID-19 cases, and over a period of several weeks that declined. In late May the number of active cases began to increase again, and this past week exceeded the peak we saw in April with 420 active infections. Looking forward, we may see a series of waves, with loosening of restrictions followed by a wave, followed by increased restrictions. This is what many of the leading epidemiologists and mathematical modelers have predicted would happen.

How do we “re-flatten” the curve?

“Flattening of the curve” has referred primarily to keeping the number of infections suppressed to a level that does not overwhelm the health system. So, in that regard it has been successful as there has not been a shortage of medical care for COVID-19 in the state. But more broadly it also refers to a goal of keeping transmission low through behavioral techniques like distancing, hand hygiene, and wearing masks. One problem with these behavioral risk reduction techniques is that they are being inconsistently applied. That is partially because some people do not believe that COVID-19 is a serious illness, or that is not likely to affect them as individuals. In addition, there are beliefs held by many that masks are not effective. Some of these erroneous beliefs are being driven by non-evidenced-based social media reports. So, first and foremost we need to keep encouraging or mandating mask use, social distancing, and hand hygiene. Concerted efforts need to be made to promote science-based recommendations, and debunking false, non-evidence-based information that undermines prevention. There is a role for leaders also to consistently reinforce prevention practices, including modeling them in their own behaviors.

What do you think of reports that two Italian doctors have suggested the virus is weakening as it spreads?

It’s most likely that the clinical improvements that are being seen in Italy are being driven by there being less virus in circulation now, and thus people are less likely to get high doses of virus. High dose exposure of virus likely leads to more severe illness. There is also good scientific evidence that the COVID-19 virus (SARS CoV-2) mutates slowly, and the mutations that have been identified are not consequential. Typically, when viruses attenuate due to mutation that takes years, and it is unlikely that a meaningful change in the genetics of the virus that would lead to a less severe disease could happen so fast.

Greenville, South Carolina, has been designated as a COVID-19 hotspot. A state health department spokeswoman has said that’s because infected individuals are infecting the people they live with. How do we keep our families safe?

The problem of inter-household viral transmission with COVID-19 is substantial. The virus is very contagious, and it can be extremely difficult to isolate a sick household member effectively, especially if they are quite ill and need care by others. This gets amplified when the residence is crowded, poorly ventilated, and does not have a separate restroom for the infected person to use. Others in the household also frequently do not have access to, or know how to use, required personal protective equipment (PPE) like N-95 masks. As well, while stay-at-home orders are highly effective at reducing community-level transmission, they do not have much effect on transmission that occurs in the household. Some municipalities in other states have provided hotel rooms to infected individuals to allow them to avoid infecting family members. Making sure that care takers have access to proper PPE, and are educated on how to use it, would be helpful as well.

Last week, a World Health Organization (WHO) expert clarified that the coronavirus can be spread by people who show no symptoms, a day after saying that the asymptomatic spread of COVID-19 was "very rare." How concerned should we be about the asymptomatic spread of the coronavirus?

As the WHO clarified, there is ample evidence that infected people without significant symptoms can spread the virus. Many epidemiologists and mathematical modelers believe that transmission from asymptomatic infected persons is a driving force behind the rapid transmission we have seen around the world. In most viral respiratory illnesses, patients are minimally infectious in the absence of symptoms. But there are multiple well-documented cases of people without COVID-19 symptoms transmitting infection to multiple other people. These events are often considered “super-spreader” events. Some modelling analyses have also suggested that a large proportion of infections are being transmitted by pre-symptomatic/asymptomatic persons, even if they are less infectious before having symptoms. This is because when symptoms develop people typically reduce their exposure to others, especially now with knowledge of COVID-19. There is also a lesson here about protecting yourself, as you cannot trust that because someone looks healthy and has no apparent symptoms that they cannot infect you. 

What do you wish the public knew about COVID-19?

The main thing I wish everyone knew is that we can as a society control the COVID-19 epidemic to a manageable level that allows our economy to operate – but only if we have solidarity, a shared evidence-based set of risk reduction strategies that we all adhere to, and we support the public health and medical efforts needed to adequately test, treat, and contact trace infections. I would also like to see the public take a more long-term view of the epidemic. I truly appreciate the optimism that people exhibit in facing the epidemic, but I worry that the public are not always realizing that in lieu of a widely available efficacious vaccine we will be living with COVID-19 for some time to come.

What do you see as our biggest challenge in returning to normal?

Probably the biggest challenge in returning to normal is to have global distribution of an efficacious vaccine. The vaccine needs to be safe, have a high degree of efficacy, and equitably available to all groups – both domestic and globally. It’s a big challenge, but the human species can accomplish amazing things if we work together. 

About the Author

Melissa Varner

Keywords: COVID-19