Table. Characteristics of measles cases by case classification, Porto, Portugal, 11 February−22 April 2018 (n = 211).
| Confirmed cases | Probable cases | Total number of notified cases | ||||
|---|---|---|---|---|---|---|
| n | % | n | % | n | % | |
| Total | 96 | 45.5 | 82 | 38.9 | 211 | 100.0 |
| Diagnostic site | ||||||
| CHP | 85 | 88.5 | 80 | 97.6 | 196 | 92.9 |
| Other | 11 | 11.5 | 2 | 2.4 | 15 | 7.1 |
| Sex | ||||||
| Female | 60 | 62.5 | 52 | 63.4 | 135 | 64.0 |
| Male | 36 | 37.5 | 30 | 36.6 | 76 | 36.0 |
| Age group (years) | ||||||
| 0–17 | 1 | 1.0 | 3 | 3.7 | 5 | 2.4 |
| 18–29 | 50 | 52.1 | 20 | 24.4 | 79 | 37.4 |
| 30–39 | 39 | 40.6 | 32 | 39.0 | 85 | 40.3 |
| 40–49 | 5 | 5.2 | 11 | 13.4 | 22 | 10.4 |
| 50–59 | 1 | 1.0 | 7 | 8.5 | 10 | 4.7 |
| 60–69 | 0 | 0.0 | 3 | 3.7 | 4 | 1.9 |
| 70–79 | 0 | 0.0 | 5 | 6.1 | 5 | 2.4 |
| 80–89 | 0 | 0.0 | 1 | 1.2 | 1 | 0.5 |
| Symptoms | ||||||
| Maculopapular rash | 84 | 87.5 | 63 | 76.8 | 147 | 69.7 |
| Fever and any of cough, coryza, conjunctivitis | 35 | 36.5 | 33 | 40.2 | 68 | 32.2 |
| Laboratory results | ||||||
| Confirmed in first analysis | 80 | 83.3 | 0 | 0.0 | 80 | 37.9 |
| Confirmed in second analysis a | 16 | 16.7 | 0 | 0.0 | 16 | 7.6 |
| Vaccination/immune status | ||||||
| No vaccination or measles history | 5 | 5.2 | 12 | 14.6 | 21 | 10.0 |
| One dose of measles vaccine | 11 | 11.5 | 14 | 17.1 | 29 | 13.7 |
| Two or more doses of measles vaccine | 67 | 69.8 | 44 | 53.7 | 126 | 59.7 |
| Presumptive immunity due to disease c | 2 | 2.1 | 2 | 2.4 | 5 | 2.4 |
| Unknown | 11 | 11.5 | 10 | 12.2 | 30 | 14.2 |
| Epidemiologic link | ||||||
| Without epidemiologic link b | 1 | 1.0 | 0 | 0.0 | 0 | 0.0 |
| Non-HCW | 9 | 9.4 | 23 | 28.0 | 38 | 18.0 |
| HCW | 86 | 89.6 | 59 | 72.0 | 173 | 82.0 |
| Physicians | 31 | 36.0 | 13 | 22.0 | 49 | 28.3 |
| Nurses | 20 | 23.3 | 27 | 45.8 | 60 | 34.7 |
| Health technicians | 6 | 7.0 | 3 | 5.1 | 11 | 6.4 |
| Medical students | 12 | 14.0 | 5 | 8.5 | 19 | 11.0 |
| Nursing students | 5 | 5.8 | 0 | 0.0 | 5 | 2.9 |
| Support staff | 12 | 14.0 | 11 | 18.6 | 29 | 16.8 |
CHP: Centro Hospitalar do Porto; HCW: healthcare workers;
a For cases where the first laboratory confirmation samples were negative or not conclusive, second samples were necessary to exclude any false negatives or to exclude IgM false positive results in unvaccinated individuals through evidence of posterior seroconversion at about 10 days after the first laboratory analysis.
b Probably the primary case of the outbreak.
c Presumptive immunity due to disease: auto reported or documented previous measles infection.