The incubation period for COVID-19 is thought to be within 14 days following exposure, with most cases occurring approximately four to five days after exposure (1). The spectrum of symptomatic infection of COVID-19 ranges from mild to critical. According to a report from the Chinese Center for Disease Control and Prevention, 81% of cases were mild (no or mild pneumonia), 14% were severe (e.g., with dyspnea, hypoxia), and 5% were critical (e.g., respiratory failure, shock, or multiorgan dysfunction). Additionally, the overall case fatality was 2.3%, with no deaths reported among non-critical cases (2). While severe illness can occur in individuals of any age, it primarily occurs in adults of middle age or older or those with underlying medical comorbidities. Comorbidities associated with severe illness and mortality include cardiovascular disease, obesity, diabetes mellitus, hypertension, chronic lung disease, cancer, and kidney disease. Pneumonia seems to be the most frequent symptom of infection, primarily characterized by fever, cough, and dyspnea (shortness of breath). Other, less common symptoms include headache, sore throat, and gastrointestinal symptoms (e.g., nausea and diarrhea) (3).
The possibility of COVID-19 should be considered primarily in patients with new onset fever and/or respiratory tract symptoms. The likelihood of having COVID-19 is increased if the patient resides in or has traveled within the past 14 days to a location where there is community transmission of the virus and/or if the patient has had close contact with a confirmed or suspected case of COVID-19 in the prior 14 days, including through work in health care settings (1). Patients with suspected COVID-19 who do not need emergency care should be encouraged to call prior to presenting to a health care facility for evaluation. Many patients can be evaluated regarding the need for testing over the phone. For patients in a healthcare facility, infection control measures should be implemented as soon as the possibility of COVID-19 is suspected.
In the United States, the CDC recommends collection of a nasopharyngeal swab specimen to test for COVID-19 (4). However, the accuracy and predictive values of SARS-CoV-2 testing have not been systematically evaluated, and the sensitivity of testing likely depends on the precise test as well as the type of specimen obtained. Negative RT-PCR tests on oropharyngeal swabs despite CT findings suggestive of viral pneumonia have been reported in some patients who ultimately tested positive for SARS-CoV-2 (4). Serologic tests, as soon as generally available and adequately evaluated, should be able to identify patients who have either a current or previous infection but a negative PCR test (1).
Home management is appropriate for patients with non-severe infection who can be adequately isolated in the outpatient setting. Management of such patients should focus on prevention of transmission to others and monitoring for clinical deterioration, which should prompt hospitalization (1). On the other hand, the management of patients requiring hospitalization
consists of ensuring appropriate infection control and supportive care. Many of these patients may develop acute respiratory distress syndrome (ARDS) and warrant intubation with mechanical ventilation (1). Although glucocorticoids were widely used in management of severe acute respiratory syndrome (SARS), the WHO and CDC recommend that they should not be used in patients with COVID-19 pneumonia unless there are other indications (eg, exacerbation of chronic obstructive pulmonary disease) (5). Additionally, some clinicians have suggested the use of non-steroidal anti-inflammatory drugs (NSAIDs) early in the course of disease may have a negative impact on disease outcome and generally should be avoided. Clinical data evaluating hydroxychloroquine or chloroquine are limited, and their efficacy against SARS-CoV-2 is unknown. Nevertheless, given the lack of clearly effective interventions and the in vitro antiviral activity, some clinicians think it is reasonable to use hydroxychloroquine in hospitalized patients with severe disease or risk for severe disease who are not eligible for clinical trials. In the United States, the FDA issued an emergency use authorization to allow the use of these agents in adolescents or adults hospitalized for COVID-19 when participation in clinical trials is not feasible (6). However, if these agents are used outside of a clinical trial, the possibility of drug toxicity and drug interactions should be considered prior to use, especially in individuals who may be more susceptible to these effects, and the patients should be monitored closely for adverse effects during use.