Characteristics and outcomes of COVID-19 patients during the BA.5 omicron wave in Tehran, Iran: a prospective observational study

BackgroundOmicron (B.1.1.529) is the fifth variant of concern of SARS-CoV-2, which has several subvariants. Clinical features of BA.1 and BA.2 infections have been described in the literature, but we have limited information about the clinical profile of BA.5, which caused the seventh wave in Iran.MethodsA prospective observational study was conducted on the BA.5 confirmed patients referred to Imam Khomeini Hospital Complex, Tehran, Iran, from 11th to 31st August 2022. The patients were divided into the two groups of outpatients and hospitalized patients, and their clinical, radiological, and laboratory data and outcomes were recorded and analyzed.ResultsWe included 193 patients with confirmed BA.5 infection, of whom 48 patients (24 center dot 8%) were hospitalized. The mean age of the patients was 45 center dot 3 +/- 16 center dot 5 years, and 113 patients (58 center dot 5%) were female. The mean number of days patients had symptoms was 6 center dot 8 +/- 2 center dot 4 days. The most common symptoms were weakness (69 center dot 9%), sore throat (67 center dot 4%), myalgia (66 center dot 3%), hoarseness (63 center dot 7%), headache (55 center dot 4%), fatigue (54 center dot 9%), and dry cough (50 center dot 3%). Fever and dyspnea were significantly more observed in the hospitalized patients (p < 0 center dot 0001). The COVID-19 vaccination rate was significantly lower in hospitalized patients than in outpatients (35/48-72 center dot 9% vs. 140/145 - 96 center dot 6%, p < 0 center dot 0001). The most common underlying diseases were hypertension (16 center dot 1%), diabetes mellitus (9 center dot 8%), and cardiovascular diseases (9 center dot 8%), all of which were significantly more common in hospitalized patients. Lung opacities were observed in 81 center dot 2% of hospitalized patients. By the end of our study, 1 center dot 5% of patients died despite receiving critical care services.ConclusionsOur findings suggested that BA.5 symptoms are more non-respiratory and usually improve within 7 days. Although the proportion of hospitalized patients is still significant, very few patients require intensive care. COVID-19 vaccination is effective in reducing the hospitalization rate.