COVID-19 was initially diagnosed in Wuhan China in December 2019, with several cases traced to the Huanan Seafood Market. Patients initially presented with unexplained cases of pneumonia for which the Chinese government took extra measures to control. Documented cases estimated an average incubation period of 5.2 days, and time to symptom manifestation of 2-14 days. The median time from symptom presentation to death is approximately 14 days. Studies suggest that disease may progress faster in the elderly, and those with chronic health conditions including Diabetes, Hypertension, and Cardiovascular disease have a high risk of contracting COVID-19. In China, COVID-19 disproportionately affects men more than women with a ratio of 3:1 (Sun, et al., 2020). This difference in male to female rates can be further understood by the virus’ mechanism of virulence.
According to Sun, et al., 2020, Angiotensin-Converting Enzyme 2 (ACE2) is the receptor for COVID-19. ACE2 is expressed on Type I and II alveolar cells in the normal lungs, and men have a higher number of ACE2 receptors than women. In the general population, Asian males have a higher number of ACE2 receptors than Asian females, and more so than Caucasians and African Americans. This explains the increased susceptibility of Asian males to COVID -19. The binding of COVID-19 to ACE2 receptors results in increased expression of ACE2 in the lungs, causing significant alveolar damage and subsequent respiratory insufficiency and failure.
Signs and symptoms of COVID-19 includes fever, runny nose, sore throat, cough, dyspnea (shortness of breath), fatigue, muscle aches, respiratory distress (difficulty breathing seen in severe cases), expectoration of sputum, hemoptysis (bloody sputum) seen in 5% of cases, and diarrhea in 3% of cases .
Affected patients are often hospitalized with initial laboratory results notable for leukopenia (low white blood cell count), lymphocytopenia (low lymphocyte count; subset of total white blood cell). Approximately 37% of patients may have abnormal liver enzymes, and 12% of patients may be diagnosed with Myocarditis (inflammation of the heart muscles) which may present with positive troponin on laboratory studies. Imaging studies preferably a chest Computed Tomography (CT) of affected individuals will reveal ground-glass opacities (GGO), interlobar septal thickening, and consolidations in bilateral lung fields. These CT findings are seen in > 95% of cases, and the severity of lung inflammation correlates with the severity clinical symptoms in affected patients (wu et al., 2020).
There is no confirmed treatment or vaccine for COVID-19. Therefore, the focus of treatment is symptomatic management of respiratory distress with supplemental oxygenation including mechanical ventilation when indicated, empiric antibiotics and antifungals to cover possible secondary infections, and appropriate infection control measures to prevent disease spread. Early identification, diagnosis, and supportive treatment can reduce morbidity and mortality from corona virus infection (Sun, et al., 2020).
Prevention measures include timely reporting of newly identified cases to appropriate health institutions and government agencies; Isolating affected individuals to avoid disease spread, avoiding interactions with affected populations, and if necessary, utilizing proper protective gear including mask, gloves, eye shield, and ensuring proper hand and environmental hygiene. In addition, it is necessary to administer supportive treatments to manage disease symptoms and decrease the risk of complications (CDC, 2020).
Most patients diagnosed with corona virus will recover from the disease, but some will have severe long-term complications particularly pulmonary fibrosis after recovery (Sun, et al., 2020). Therefore, measures to prevent deterioration of lung function, reduce lung inflammation and permanent damage should be implemented early, with ongoing research to improve long-term treatment options and outcomes.
Written by Dr. Idongesit Bassey
References
Sun, P., Lu, X., Xu, C., Sun, W., & Pan, B. (2020). Understanding of COVID-19 based on current evidence. Journal of Medical Virology, doi: 10.1002/jmv.25722 Wu, J., Wu, X., Zeng, W., Guo, D., Fang, Z., Chen, L., … Li., C. (2020). Chest CT findings in patients with corona virus disease 2019 and its relationship with clinical features. Investigative Radiology, doi: 10.1097/RLI.00000000000000670