An observational retrospective cohort study published in “PLoS One” demonstrated that the symptoms of coronavirus-infected patients in high altitude areas are mild. Furthermore, about one-third were asymptomatic. Numerous independent risk factors were identified for the symptomatic cases of COVID-19.

Investigators undertook this study to explore the differences in the clinical manifestation and treatment of SARS-CoV-2 between high altitude and low altitude areas. Also, the risk factors for symptomatic cases of coronavirus were evaluated.

Extraction of the clinical characteristics, and laboratory and radiological features of 67 patients infected with coronavirus were done. Notably, 6% (n=4) patients were categorized as severe cases; 58.2% (n=39) were non-severe cases, and 35.8% (n=24) patients were asymptomatic cases. As found, 68.7% (n=46) patients were linked with cluster infection events. Dyspnea, cough, myalgia, sputum production, headache, and fatigue were the most commonly noted symptoms.

Leucopenia and lymphopenia were witnessed in 10.4% (n=7) and 29.9% (n=20) patients respectively. The neutrophil-to-lymphocyte ratio and lymphocyte counts were found to be distinct between the three groups. Overall, 20.9% (n=14) patients had thrombocytopenia, and prothrombin times and fibrinogen levels differed between the groups. Substantial differences were reported in the levels of sodium, chloride, and calcium between the three arms.

The antiviral treatment did not cause side effects or minimized the duration from initial positive to subsequently negative nuclei acid tests. For the symptomatic cases of SARS-CoV-2, hypertension, advanced age, neutrophil-to-lymphocyte ratio, elevated neutrophil count, levels of fibrinogen and lactate dehydrogenase were recognized as independent risk factors.