The Centers for Disease Control reported Monday, October 5, 2020 that there is increasing evidence that children and adolescents can efficiently transmit SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19). During July–August 2020, four state health departments and the CDC investigated a COVID-19 outbreak that occurred during a 3-week duration family gathering of five households in which an adolescent female aged 13 years was the index and suspected primary patient; 11 subsequent cases occurred. All 11 individuals recovered, and only two sought hospital care.
The 13 year-old girl was tested by a rapid antigen test because of a known exposure to a prior large COVID-19 outbreak in June 2020, but the test, which was administered 4 days after the exposure and when she had no symptoms, was negative.
Following the family gathering outbreak, both heads of each household were interviewed to assess demographic characteristics, exposures, symptoms, close contacts, and outcomes. Parents provided data for all children, adolescents, and young adults. Thirteen of the 13 year-old index patient’s relatives sought viral testing; test results were reported by respondents, and all test results that were reported to be positive were verified in state reporting systems.
For three children and adolescents who were not tested while symptomatic, a chemiluminescent immunoassay detecting total antibody to SARS-CoV-2 was performed 28–46 days after symptom onset. The results were positive for all three children and adolescents, including the index patient and her two brothers, indicating earlier infection. Likely exposure periods and infectious periods were estimated from symptom onset dates. This activity was reviewed by the CDC and was conducted consistent with applicable federal law and CDC policy.
Background
While away from home, the 13 year-old female index patient was exposed during a large COVID-19 outbreak in June 2020. Because of her exposure, she sought testing for SARS-CoV-2 after returning home. A rapid antigen test performed 4 days after exposure, when she was asymptomatic, was negative). She experienced nasal congestion 2 days later, which was her only symptom. That same day, she, her parents, and two brothers traveled to meet 15 other relatives at the gathering, which began the following day. Attendees belonged to five households in four states and ranged in age from 9 to 72 years. Fourteen relatives, including the index patient, stayed in a five-bedroom, two-bathroom house for 8–25 days. These relatives did not wear face masks or practice physical distancing. An additional six relatives (an aunt, an uncle, and four cousins) visited for 10 hours on day 3 and 3 hours on day 10, when six overnight attendees were potentially infectious. These six relatives maintained physical distance and remained outdoors; none wore face masks.
Among the 14 persons who stayed in the same house, 12 experienced symptoms and were subsequently found to have COVID-19 based on Council of State and Territorial Epidemiologists definitions. Six cases were confirmed by reverse transcription–polymerase chain reaction (RT-PCR) testing, four persons were classified as having probable COVID-19 based on positive antigen testing or clinical and epidemiologic criteria, and two persons were classified as having suspected COVID-19 based on positive antibody testing, including the 13 year-old index patient. The other two overnight attendees never experienced symptoms, including one who received a negative SARS-CoV-2 RT-PCR test result 4 days after the last exposure. One person with COVID-19 was hospitalized and another sought emergency department care for respiratory symptoms; both recovered.
None of the six relatives who remained outdoors and maintained physical distance developed symptoms; four had negative RT-PCR test results 4 days after the last exposure, and two were not tested. Relatives with COVID-19 were advised by state investigators to self-isolate, and contacts were advised to self-quarantine.
Eight relatives reported activities outside the gathering during their exposure periods that might have increased their risks for exposure. However, only the index patient reported exposure to a person with confirmed COVID-19 or compatible symptoms outside the family. The 13 year-old index patient’s high-risk exposure and symptom onset 3–19 days before that of any other person at the family gathering support the hypothesis that this adolescent’s infection was the source of the family outbreak. The adolescent’s initial antigen test result was likely a false negative because it was performed before symptom onset; the only antigen test that had Food and Drug Administration Emergency Use Authorization at the time was intended for use within the first 5 days of symptoms.
This outbreak highlights five important issues
First, children and adolescents can serve as the source for COVID-19 outbreaks within families, even when their symptoms are mild. Better understanding of transmission by children and adolescents in different settings is needed to refine public health guidance.
Second, this investigation provides evidence of the benefit of physical distancing as a mitigation strategy to prevent SARS-CoV-2 transmission. None of the six family members who maintained outdoor physical distance without face masks during two visits to the family gathering developed symptoms; the four who were tested for SARS-CoV-2 had negative test results.
Third, rapid antigen tests generally have lower sensitivity (84.0%–97.6%) compared with RT-PCR testing; negative results should be confirmed with RT-PCR if used for persons with high pretest probability of infection, such as those with a known exposure.
Fourth, regardless of negative test results, persons should self-quarantine for 14 days after a known exposure (5) or after travel when mandated by state, territorial, tribal, or local authorities.
Fifth, SARS-CoV-2 can spread efficiently during gatherings, especially with prolonged, close contact. Physical distancing, face mask use, and hand hygiene reduce transmission; and gatherings should be avoided when physical distancing and face mask use are not possible.
Acknowledgments
The family described in this report; Alyjah Benton, Julia Brida, Lydia Brown, Rhiannon Cappetta, Peter Pleskunas, Elier Reyes, Theodore Marak, Tara Cooper, Susan Soliva, Rachel Rubin, Alicia Fry, Robert Slaughter, Ramika Archibald, Elizabeth Dietrich, Anupama Shankar, Emilio Dirlikov, Julie Villanueva, Margaret Honein, Dale Rose, Leah Graziano, Mark Johnson, Kathy Fowler, Prabasaj Paul, Rachel Slayton, Lili Punkova, Joe Sexton, Hannah Browne, Amy Schuh, Holly Hughes, Marla Petway, Leslie Dauphin, Brandi Limbago, CDC COVID-19 Response Team.
Authors
Noah G. Schwartz, MD; Anne C. Moorman, MPH; Anna Makaretz, ScM; Karen T. Chang, PhD; Victoria T. Chu, MD; Christine M. Szablewski, DVM; Anna R. Yousaf, MD; Marie M. Brown, MPH4; Ailis Clyne, MD; Amanda DellaGrotta, MPH; Jan Drobeniuc, MD, PhD; Jacqueline Korpics, MD; Adam Muir, MSc; Cherie Drenzek, DVM; Utpala Bandy, MD; Hannah L. Kirking, MD; Jacqueline E. Tate, PhD; Aron J. Hall, DVM; Tatiana M. Lanzieri, MD; Rebekah J. Stewart, MSN, MPH
Corresponding author: Noah G. Schwartz
Get updates from The Cardinal ALL NEWS FEEDS on Facebook. Just ‘LIKE’ the ‘Arlington Cardinal Page (become a fan of our page). The updates cover all posts and sub-category posts from The Cardinal — Arlingtoncardinal.com. You can also limit feeds to specific categories. See all of The Cardinal Facebook fan pages at Arlingtoncardinal.com/about/facebook …
Help fund The Cardinal Arlingtoncardinal.com/sponsor