Table 1. Characteristics of study participants (n = 522)
Symptomatic patients(n = 304, 58.2%)Asymptomatic patients (n = 218, 41.8%)
Prison officers(n = 139, 26.6%)Health workers(n = 39, 7.5%)Contacts(n = 40, 7.7%)
CharateristicsMean ± SD / Prevalence % (95% CI)
Mean age, years, mean ± SD42.5 ± 15.332.7 ± 6.833.0 ± 9.037.3 ± 13.8
Women (n = 217)53.6 (48.0 to 59.2)5.8 (1.9to 9.6)76.9 (63.7 to 90.1)40.0 (24.8 to 55.2)
Current smoker (n = 149)34.8 (28.9 to 40.8)37.3 (27.5to 47.2)22.6 (6.7 to 38.5)27.5 (12.3 to 42.7)
Medications
ARBs (n = 37)9.0 (6.1 to 11.9)10.1 (0.0 to 21.6)17.0 (5.3 to 28.7)
ACE inhibitors (n = 14)4.0 (1.9 to 6.1)6.1 (0.0 to 17.0)
NSAIDs (n = 16)3.1 (1.6 to 4.5)
Oral steroids (n = 5)1.3 (0.0 to 2.6)2.6 (0.0 to 7.7)
Inhalator steroids (n = 16)4.8 (2.5to 7.0)3.7 (0.0 to 10.6)
Chronic diseases
High blood pressure (n = 76)15.4 (12.1 to 18.7)9.8 (28.8to 16.8)17.8 (5.5 to 30.1)13.7 (4.1 to 23.2)
Diabetes (n = 31)8.4 (5.6 to 11.1)5.9 (0.0 to 16.0)7.1 (0.0 to 15.8)
Asthma or COPD (n = 33)8.7 (5.6 to 11.8)1.0 (0.0 to 3.1)5.3 (0.0 to 12.4)
Cardiovascular disease (n = 9)1.7 (0.7 to 2.7)
Cancer (n = 6)1.1 (0.2 to 2.1)
Prevalence RT-PCR positive (n = 100)27.5 (22.1 to 32.8)7.9 (3.4 to 12.3)8.8 (0.0 to 18.4)7.5 (0.0 to 15.6)
Prevalence of IgM(+) or IgG (+) ever (n = 70)18.5 (14.1 to 23.0)4.4 (0.5 to 8.2)3.2 (0.0 to 9.4)7.8 (0.0 to 16.2)
IgM (+) or IgG (+) by days of initial symptomsa:
Baseline (median: 3 days; [0–21]) (n = 25)5.7 (3.1 to 8.3)3.3 (0.0 to 6.8)3.9 (0.0 to 11.3)2.7 (0.0 to 7.7)
Follow-up 1 (median: 11 days; [6–24]) (n = 7)b 1.9 (0.0 to 3.9)1.0 (0.0 to 3.1)2.5 (0.0 to 7.7)3.0 (0.0 to 8.9)
Follow-up 2 (median: 19 days [12–33]) (n = 48)c 18.0 (13.3 to 22.6)5.6 (0.0 to 13.2)
Initial symptoms profile (only symtpomatic patients)
Symptoms Prevalence % ( 95% CI ) Symptoms Prevalence % ( 95% CI )
Cephalea (n = 202)66.9 (61.7 to 72.1)Fatigue (n = 49)16.2 (12.1 to 20.4)
Dry cough (n = 141)46.7 (41.1 to 52.3)Productive cough (n = 44)14.6 (10.7 to 18.5)
Sore throat (n = 137)45.4 (39.8 to 50.9)Fever (n = 44)14.6 (10.6 to 18.5)
Myalgia (n = 128)42.4 (36.8 to 47.9)Nasal congestion (n = 42)13.9 (10.0 to 17.8)
Feverish sensation (n = 83)27.5 (22.5 to 32.5)Chest pain (n = 40)13.2 (9.4 to 17.0)
Diarrhoea (n = 57)18.9 (14.5 to 23.2)Anosmia (n = 30)9.9 (6.6 to 13.3)
Disnea (n = 53)17.5 (13.4 to 21.7)Dysgeusia (n = 22)7.3 (4.4 to 10.2)
  • aPrevalence data are adjusted by age, and sex using logistic regression. Age mean data are adjusted by sex using linear regression. bFollow-up 1: follow-up in first time period n = 381. bfollow-up 2: follow-up in second time period n = 447. ARBs = angiotensin receptor blockers; ACE = angiotensin-converting-enzyme; NSAIDs = non-steroidal anti-inflammatory drugs; COPD = chronic obstructive pulmonary disease; RT-PCR = reverse transcriptase-polymerase chain reaction; IgM = immunoglobulin M; IgG = immunoglobulin G