TABLE 1.
Clinical and epidemiological data obtained from participants.
| Variable | Level | Overall n (%) | First survey n (%) | Second survey n (%) | Third survey n (%) | p-value |
| Administrative Regions | Alterosas | 634 (19.6%) | 198 (18.4%) | 218 (20.2%) | 218 (20.2%) | 0.9584 |
| Citrolândia | 219 (6.8%) | 83 (7.7%) | 68 (6.3%) | 68 (6.3%) | ||
| Icaivera | 62 (1.9%) | 20 (1.9%) | 21 (1.9%) | 21 (1.9%) | ||
| Imbiruçu | 565 (17.4%) | 183 (17.0%) | 191 (17.7%) | 191 (17.7%) | ||
| Norte | 333 (10.3%) | 111 (10.3%) | 111 (10.3%) | 111 (10.3%) | ||
| Petrovale | 41 (1.3%) | 13 (1.2%) | 14 (1.3%) | 14 (1.3%) | ||
| PTB | 290 (9.0%) | 108 (10.0%) | 91 (8.4%) | 91 (8.4%) | ||
| Sede | 583 (18.0%) | 201 (18.6%) | 191 (17.7%) | 191 (17.7%) | ||
| Terezópolis | 319 (9.8%) | 109 (10.1%) | 105 (9.7%) | 105 (9.7%) | ||
| Vianópolis | 193 (6.0%) | 53 (4.9%) | 70 (6.5%) | 70 (6.5%) | ||
| Sex | Female | 1628 (50.3%) | 548 (50.8%) | 536 (49.6%) | 544 (50.4%) | 0.8619 |
| Age range | 0–5 | 217 (6.7%) | 71 (6.6%) | 73 (6.8%) | 73 (6.8%) | 1.0000 |
| 6–19 | 650 (20.1%) | 218 (20.2%) | 217 (20.1%) | 215 (19.9%) | ||
| 20–39 | 1067 (32.9%) | 354 (32.8%) | 355 (32.9%) | 358 (33.1%) | ||
| 40–59 | 871 (26.9%) | 291 (27.0%) | 289 (26.8%) | 291 (26.9%) | ||
| Above 60 | 434 (13.4%) | 145 (13.4%) | 146 (13.5%) | 143 (13.2%) | ||
| Pneumopathy | Yes | 30 (0.9%) | 7 (0.6%) | 13 (1.2%) | 10 (0.9%) | 0.4042 |
| Chronic neurological disease | Yes | 39 (1.2%) | 16 (1.5%) | 10 (0.9%) | 13 (1.2%) | 0.4948 |
| Pregnant | Yes | 28 (0.9%) | 10 (0.9%) | 11 (1.0%) | 7 (0.6%) | 0.6257 |
| Postpartum | Yes | 9 (0.3%) | 2 (0.2%) | 3 (0.3%) | 4 (0.4%) | 0.7165 |
| Chronic cardiovascular disease | Yes | 96 (3.0%) | 34 (3.2%) | 39 (3.6%) | 23 (2.1%) | 0.1154 |
| Chronic kidney disease | Yes | 50 (1.5%) | 24 (2.2%) | 12 (1.1%) | 14 (1.3%) | 0.0799 |
| Obesity | Yes | 105 (3.2%) | 33 (3.1%) | 37 (3.4%) | 35 (3.2%) | 0.8903 |
| Asthma | Yes | 173 (5.3%) | 65 (6.0%) | 58 (5.4%) | 50 (4.6%) | 0.3537 |
| Immunodepression | Yes | 22 (0.7%) | 9 (0.8%) | 5 (0.5%) | 8 (0.7%) | 0.5507 |
| Chronic liver disease | Yes | 15 (0.5%) | 4 (0.4%) | 7 (0.6%) | 4 (0.4%) | 0.5478 |
| Diabetes | Yes | 228 (7.0%) | 78 (7.2%) | 74 (6.9%) | 76 (7.0%) | 0.9430 |
| Hypertension | Yes | 563 (17.4%) | 190 (17.6%) | 186 (17.2%) | 187 (17.3%) | 0.9698 |
| Transplanted | Yes | 4 (0.1%) | 2 (0.2%) | 1 (0.1%) | 1 (0.1%) | 0.7780 |
| Cancer | Yes | 23 (0.7%) | 10 (0.9%) | 8 (0.7%) | 5 (0.5%) | 0.4342 |
| Any comorbidity | Yes | 955 (29.5%) | 327 (30.3%) | 320 (29.6%) | 308 (28.5%) | 0.6552 |
| Fever | Yes | 224 (6.9%) | 66 (6.1%) | 70 (6.5%) | 88 (8.1%) | 0.1398 |
| Cough | Yes | 648 (20.0%) | 185 (17.1%) | 213 (19.7%) | 250 (23.1%) | 0.0022 |
| Sore throat | Yes | 397 (12.3%) | 112 (10.4%) | 125 (11.6%) | 160 (14.8%) | 0.0051 |
| Dyspnoea | Yes | 141 (4.4%) | 49 (4.5%) | 46 (4.3%) | 46 (4.3%) | 0.9336 |
| Myalgia | Yes | 284 (8.8%) | 74 (6.9%) | 99 (9.2%) | 111 (10.3%) | 0.0165 |
| Rhinorrhea | Yes | 717 (22.1%) | 205 (19.0%) | 240 (22.2%) | 272 (25.2%) | 0.0025 |
| Respiratory discomfort | Yes | 188 (5.8%) | 63 (5.8%) | 58 (5.4%) | 67 (6.2%) | 0.7084 |
| Nausea/vomit | Yes | 120 (3.7%) | 37 (3.4%) | 39 (3.6%) | 44 (4.1%) | 0.7156 |
| Headache | Yes | 790 (24.4%) | 244 (22.6%) | 259 (24.0%) | 287 (26.6%) | 0.0936 |
| Prostration | Yes | 188 (5.8%) | 60 (5.6%) | 51 (4.7%) | 77 (7.1%) | 0.0523 |
| Diarrhea | Yes | 211 (6.5%) | 59 (5.5%) | 76 (7.0%) | 76 (7.0%) | 0.2336 |
| Conjunctivitis | Yes | 32 (1.0%) | 13 (1.2%) | 11 (1.0%) | 8 (0.7%) | 0.5478 |
| Ageusia/anosmia | Yes | 101 (3.1%) | 30 (2.8%) | 30 (2.8%) | 41 (3.8%) | 0.2914 |
| Loss of voice | Yes | 56 (1.7%) | 18 (1.7%) | 13 (1.2%) | 25 (2.3%) | 0.1381 |
| Sought health assistance | Hospital | 138 (4.3%) | 41 (3.8%) | 41 (3.8%) | 56 (5.2%) | 0.1492 |
| Basic Health Unit | 129 (4.0%) | 42 (3.9%) | 41 (3.8%) | 46 (4.3%) | ||
| Emergency Care Unit | 127 (3.9%) | 38 (3.5%) | 35 (3.2%) | 54 (5.0%) | ||
| None | 2845 (87.8%) | 958 (88.8%) | 963 (89.2%) | 924 (85.6%) | ||
| Admitted to a health institution | Yes | 38 (1.2%) | 11 (1.0%) | 12 (1.1%) | 15 (1.4%) | 0.7085 |
| International travel | Yes | 14 (0.4%) | 10 (0.9%) | 4 (0.4%) | 0 (0.0%) | 0.0043 |
| Household contact with symptomatic person | Yes | 640 (19.8%) | 157 (14.6%) | 193 (17.9%) | 290 (26.9%) | <0.0001 |
| Sorological test | Reactive | 39 (1.2%) | 3 (0.3%) | 8 (0.7%) | 28 (2.6%) | <0.0001 |
| Non-reactive | 3200 (98.8%) | 1076 (99.7%) | 1072 (99.3%) | 1052 (97.4%) | ||
| PCR test | Detected | 84 (2.6%) | 2 (0.2%) | 22 (2.0%) | 60 (5.6%) | <0.0001 |
| Undetected | 3112 (96.1%) | 1035 (95.9%) | 1057 (98.0%) | 1020 (94.4%) | ||
| Indeterminate | 42 (1.3%) | 42 (3.9%) | 0 (0.0%) | 0 (0.0%) | ||
| Prevalence | Sorological reactive and/or PCR detected | 106 (3.3%) | 5 (0.5%) | 29 (2.7%) | 72 (6.7%) | <0.0001 |
Bolded p-values indicate p < 0.05.