Table 2.
Severe acute respiratory syndrome coronavirus 2 infection rates in pregnancy in Washington State
| ACH region | Washington State COVID-19 in Pregnancy Collaborative |
Washington State: 20–39 y |
RR |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cases in pregnancy |
Deliveries during the study period |
SARS-CoV-2 infection rate per 1000 deliveries |
Casesa |
Populationb n |
SARS-CoV-2 infection rate per 1000 |
||||||||
| n | (%) | n | (%) | Rate | (95% CI) | n | (%) | Rate | (95% CI) | RR | (95% CI) | ||
| Better Health Together or North Central | 14 | (5.8) | 1318 | (7.6) | 10.6 | (6.3–17.9) | 1746 | (11.5) | 214,300 | 8.1 | (7.8–8.5) | 1.3 | (0.7–2.2) |
| Greater Columbia | 88 | (36.7) | 2653 | (15.4) | 33.2 | (26.9–40.9) | 5459 | (35.8) | 193,851 | 28.2 | (27.4–28.9) | 1.2 | (0.9–1.4) |
| King | 94 | (39.2) | 7283 | (42.3) | 12.9 | (10.5–15.8) | 4274 | (28.0) | 744,386 | 5.7 | (5.6–5.9) | 2.2 | (1.8–2.8) |
| North Sound | 16 | (6.7) | 2506 | (14.5) | 6.4 | (3.9–10.4) | 1752 | (11.5) | 325,671 | 5.4 | (5.1–5.6) | 1.2 | (0.7–1.9) |
| Pierce | 17 | (7.1) | 1696 | (9.8) | 10.0 | (6.2–16.1) | 1173 | (7.7) | 239,814 | 4.9 | (4.6–5.2) | 2.0 | (1.2–3.3) |
| SW Washington State Regional Health, Olympic, or Cascade Pacific Action Alliance | 11 | (4.6) | 1777 | (10.3) | 6.2 | (3.4–11.2) | 834 | (5.5) | 358,226 | 2.3 | (2.2–2.5) | 2.7 | (1.3–4.8) |
| Washington State total | 240 | 17,233 | 13.9 | (8.3–23.2)c | 15,238d | 2,076,248 | 7.3 | (7.2–7.4) | 1.7 | (1.3–2.3)e | |||
Adapted from the Washington State Department of Health and the Washington State Office of Financial Management.21,22
ACH, Accountable Community of Health; CI, confidence interval; COVID-19, coronavirus disease 2019; RR, rate ratio; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.
Lokken et al. Severe acute respiratory syndrome coronavirus 2 infection rate in pregnancy. Am J Obstet Gynecol 2021.
Case data were calculated from March 1, 2020, to June 28, 2020 (closest available date to June 30, 2020) using the “COVID-19 in Washington State: Confirmed Cases, Hospitalizations and Deaths by Week of Illness Onset, County, and Age” data set available from the Washington State Department of Health at https://www.doh.wa.gov/Emergencies/COVID19/DataDashboard. Counts include females and males
Population estimate calculated using the 2019 postcensal population estimates from the Washington State Office of Financial Management
Infection rates were calculated with Poisson regression with additional clustering by ACH for the statewide estimate
The overall number of SARS-CoV-2 cases through June 28, 2020 was 15,238, but 20 cases were not assigned to an ACH region
The statewide rate ratio is an ACH-weighted state estimate.