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Volume 32, Number 7—July 2026
Dispatch
Household Transmission of Enterovirus D68, Washington and Oregon, United States, 2022–2024
, Erica Wetzler, Anna Elias-Warren, Katherine L. Hoffman, Alex Harteloo, Hyeong Geon Kim, Kevin Kong, Hong Xie, Jolene Gov, Margaret G. Mills, Collrane Frivold, Madison Hollcroft, Mark Drummond, Tara Hatchie, Erica Clark, Brenna Ehmen, Peter D. Han, Luis Gamboa, Sally Grindstaff, Jeremy Stone, Alexander L. Greninger, Lea M. Starita, Christina Lockwood, Janet A. Englund, Marco Carone, Ana A. Weil, Sacha L. Reich, Richard A. Mularski, Mark A. Schmidt, Jennifer L. Kuntz, Allison L. Naleway, and Helen Y. Chu
Table 2
Characteristics of households and household contacts in study of household transmission of enterovirus D68, Washington and Oregon, United States, 2022–2024*
| Characteristics | Potential secondary transmission† | Unlikely secondary transmission‡ | Total |
|---|---|---|---|
| No. households |
7 |
28 |
35 |
| Household density§ | |||
| 2–4 persons | 6 (85.7) | 24 (85.7) | 30 (85.7) |
| >5 persons |
1 (14.3) |
4 (14.3) |
5 (14.3) |
| Housing type | |||
| House, condo, or townhouse | 7 (100) | 27 (96.4) | 34 (97.1) |
| Missing |
0 |
1 (3.6) |
1 (2.9) |
| Household enrollment | |||
| Median no. participants (range) | 3 (2–4) | 3 (2–4) | 3 (2–4) |
| No children <5 y | 5 (71.4) | 17 (60.7) | 22 (62.9) |
| Child <5 y, but no childcare | 1 (14.3) | 2 (7.1) | 3 (8.6) |
| Child <5 y in childcare¶ |
1 (14.3) |
9 (32.1) |
10 (28.6) |
| Income >$100,000 |
3 (42.9) |
22 (78.6) |
25 (71.4) |
| Smoker in household |
1 (14.3) |
2 (7.1) |
3 (8.6) |
| Study site | |||
| Kaiser Permanente Northwest | 4 (57.1) | 12 (42.9) | 16 (44.4) |
| University of Washington |
3 (42.9) |
16 (57.1) |
19 (54.3) |
| No. household contacts |
15 |
51 |
66 |
| No. swab samples tested from symptomatic participants |
14 |
20 |
34 |
| Median age, y (range) |
42 (2–48) |
38 (3–49) |
38.5 (2–49) |
| Age range | |||
| 6 mo–1 y | 0 | 0 | 1 (1.4) |
| 2–4 y | 1 (6.7) | 1 (2.0) | 1 (1.7) |
| 5–12 y | 3 (20.0) | 17 (33.3) | 22 (31.4) |
| 13–50 y |
11 (73.3) |
33 (64.7) |
45 (64.3) |
| Female sex at birth |
9 (60.0) |
30 (58.8) |
39 (59.1) |
| Sex | |||
| F | 9 (60.0) | 29 (56.9) | 38 (57.6) |
| M | 6 (40.0) | 21 (41.2) | 27 (40.9) |
| Other |
0 |
1 (2.0) |
1 (1.5) |
| Race or ethnicity | |||
| Asian | 2 (13.3) | 2 (3.9) | 4 (6.1) |
| White | 11 (73.3) | 44 (86.3) | 55 (83.3) |
| Multiracial | 2 (13.3) | 5 (9.8) | 7 (10.6) |
| Hispanic |
0 |
4 (7.8) |
4 (6.1) |
| Any smoking |
1 (6.7) |
2 (3.9) |
3 (4.5) |
| Any underlying conditions# |
10 (66.7) |
23 (45.1) |
33 (50.0) |
| Masking in public | |||
| Any | 14 (93.3) | 48 (94.1) | 62 (93.9) |
| Never | 1 (6.1) | 3 (5.9) | 4 (6.1) |
*Values are no. (%) except as indicated. ARI, acute respiratory illness; EV, enterovirus; HPIV, human parainfluenza virus; RSV, respiratory syncytial virus. †Occurring when EV-D68 is detected in a secondary household member 1–14 days after index case. ‡Unlikely secondary transmission defined as occurring when only 1 EV-D68 case was detected in the household or when >2 EV-D68 cases were in a household but secondary case detected >14 days after index case. §Household density represents the number of household members regardless of enrollment in the study; thus, numbers might be greater than the number of participants enrolled in the study, if not all household members were enrolled. ¶Daycare or school attendance among >1 child <5 years in the household as reported at enrollment. #Underlying conditions include asthma, chronic obstructive pulmonary disease (including chronic bronchitis and emphysema), sleep apnea, heart disease, congenital heart disease, heart failure, Down syndrome, hypertension (high blood pressure), diabetes (high blood sugar), liver condition, weak or failing kidneys, cancer or malignancy, arthritis, stroke, deep vein thrombosis or pulmonary embolism, sickle cell disease or thalassemia, weakened immune system, depression, anxiety, thyroid issues, or other health diagnosis.