On Jan 21, 2020, the first 5 COVID-19 pneumonia cases emerged in 4 different cities in Zhejiang province. Later, the number of new confirmed cases rapidly increased every day, and reached the top on Jan 29. Then, the new cases began to decline continuously, except Feb 3. All 11 cities have been infected with the COVID-19 in Zhejiang province, especially Wenzhou, which has accounted for nearly half of the total cases. However, the new cases in other cities almost never above 25 (Fig1. A, C and D). Until Feb 11, although there were accumulative 1143 confirmed case in Zhejiang province, the new added cases has decreased to less than 25. The outbreak has been effectively and quickly under the control (Fig1.A and B).
The earliest 3 days' confirmed patients all have Wuhan-living and travelling history. Since Jan 23, patients who have not gone to Wuhan began to emerge, indicating that the infection spread in Zhejiang. When enter February, most of the new infected cases were without Wuhan-living and travelling history (Fig2).
The patients have no gender distinction, with 544 (50.4%) male and 535 (49.6%) Female. Their age ranged from a few months to 90's years, and median age is 47 years (SD:15). The average time from initial symptoms appear to confirm is 5.9 days (SD: 4.0), and half of them spend only not longer than 5 days (Table1).
Similar as reported in other studies, most patients had fever (700, 72.2%) or cough (388, 40.0%) and weakness (112, 11.5%). 89 (9.2%) patients had expectoration. 83 (8.6%) patients had headache. 65 (6.7%) patients had muscle ache. Other symptoms included pharyngeal discomfort (102 [10.5%]), chills(52 [5.4%]), dizziness (30 [3.1%]), nasal obstruction (26 [2.7%]), diarrhoea (25 [2.6%]), chest tightness (25 [2.6%]), runny nose (25 [2.6%]), difficulty in breathing (10 [1.0%]), nausea and vomiting (7 [0.7%]), poor appetite (5 [0.5%]), abdominal pain (3 [0.3%]), chest pain (2 [0.2%]), palpitation (2 [0.2%]) and gastrointestinal discomfort (2 [0.2%]). Only one case with each following symptoms, including photophobia, redness and swelling of the eyes, soreness of waist. Besides, 13 [1.3%] patients have no clinical symptoms, but CT examination show pneumonia. 258 cases have been issued the earliest imaging examination results, in which, 242 [93.8%] patients have pathological changes, and 16 [6.2%] patients have no changes (Table2). Interestingly, We found that the earliest CT examination results related to the age. Patients with no CT changes were younger than patients with CT pathological changes (Fig3).
To find whether the symptoms related to age, we also compared the elders (older than 65 years ) and the young (younger than 65 ) with COVID-19 infection in Zhejiang province. In general, the differences between them were not significant, except that more young patients show pharyngeal discomfort, headache, and dizziness (Table3).
Among all confirmed patients, about 7% were severe (declined from more than 15% at the beginning). Since Jan 23, some patients discharged the hospital, and starting from Jan 28, the number of discharged cases increased every day. Until Feb 11, 279 patients had discharged the hospital (Table 1 and Fig4 ).