Volume 28, Number 3—March 2022
Research Letter
Serial Intervals and Household Transmission of SARS-CoV-2 Omicron Variant, South Korea, 2021
Table
Characteristics of SARS-CoV-2 Omicron (B.1.1.529) variant of concern of index case-patients and household members, South Korea, 2021*
| Household | Index case-patient |
Household members† |
|||||
|---|---|---|---|---|---|---|---|
| Age, y/sex | Transmission route | Signs/symptoms at diagnosis | COVID-19 vaccination status (vaccine)‡ | No. members, n = 36 | No. confirmed cases, n = 18 | ||
| 1 |
44/M |
Imported case |
Cough, sputum, sore throat |
Fully (mRNA-1273) |
2 |
1 |
|
| 2 |
38/M |
Contact with a confirmed case at the airport |
Fever, cough, myalgia |
Unvaccinated |
2 |
1 |
|
| 3 |
33/M |
Contact at church and restaurant |
Fever, cough, myalgia, headache |
Unvaccinated |
1 |
1 |
|
| 4 |
39/F |
Contact at church |
Fever, myalgia |
Partially (BNT162b) |
1 |
0 |
|
| 5 |
31/F |
Contact at church |
Myalgia |
Unvaccinated |
0 |
0 |
|
| 6 |
27/F |
Contact at church |
Fever, sore throat |
Unvaccinated |
1 |
1 |
|
| 7 |
33/F |
Contact at church |
Fever, chill, cough, myalgia, headache |
Unvaccinated |
2 |
2 |
|
| 8 |
34/F |
Contact at church |
Sore throat |
Unvaccinated |
2 |
1 |
|
| 9 |
50/F |
Contact at church |
Cough, sore throat, headache |
Fully (Ad26.COV2.S) |
1 |
1 |
|
| 10 |
56/F |
Contact with a friend |
Cough, fatigue |
Fully (Ad26.COV2.S) |
0 |
0 |
|
| 11 |
46/M |
Contact at church |
Asymptomatic |
Fully (mRNA-1273) |
0 |
0 |
|
| 12 |
39/F |
Contact at a restaurant |
Sore throat |
Unvaccinated |
2 |
2 |
|
| 13 |
77/F |
Contact at church |
Cough, sore throat |
Fully (BNT162b) |
2 |
0 |
|
| 14 |
44/F |
Contact at church |
Sputum, sore throat |
Fully (mRNA-1273) |
1 |
1 |
|
| 15 |
6/M |
Contact at a childcare center |
Asymptomatic |
Unvaccinated |
2 |
0 |
|
| 16 |
31/F |
Contact at church |
Fever, sputum, sore throat |
Unvaccinated |
1 |
0 |
|
| 17 |
23/F |
Contact with a friend |
Fever, chill, cough, sputum, sore throat, myalgia, headache |
Fully (mRNA-1273) |
1 |
0 |
|
| 18 |
4/M |
Contact at street |
Asymptomatic |
Unvaccinated |
3 |
0 |
|
| 19 |
64/F |
Contact at church |
Asymptomatic |
Fully (mRNA-1273) |
0 |
0 |
|
| 20 |
67/F |
Contact at church |
Asymptomatic |
Unvaccinated |
1 |
1 |
|
| 21 |
34/F |
Contact at church |
Fever, myalgia |
Unvaccinated |
1 |
1 |
|
| 22 |
33/F |
Contact at church |
Sore throat, rhinorrhea |
Fully (BNT162b) |
2 |
0 |
|
| 23 |
45/F |
Contact with a family member |
Asymptomatic |
Fully (Ad26.COV2.S) |
2 |
1 |
|
| 24 |
2/F |
Contact at playground |
Fever, rhinorrhea |
Unvaccinated |
4 |
3 |
|
| 25 |
3/M |
Contact at a childcare center |
Asymptomatic |
Unvaccinated |
2 |
1 |
|
| Total |
NA |
NA |
NA |
36 |
18 |
||
| Attack rate | NA | NA | NA | NA | 0.50 | ||
*COVID-19, coronavirus disease; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2. †Household members who participated in church service on November 28, 2021, were excluded. ‡An unvaccinated person had received no COVID-19 vaccine. A partially vaccinated person had received a COVID-19 vaccine but had not completed the primary series >14 d before illness onset. A fully vaccinated person had completed the primary series of COVID-19 vaccine >14 d before illness onset; vaccinated index case-patients received BNT162b, n = 3; mRNA-1273, n = 5; or Ad26.COV2.S, n = 3.
1These authors contributed equally to this article.