First Mildly Ill, Nonhospitalized Case of Coronavirus Disease 2019 (COVID-19) Without Viral Transmission in the United States—Maricopa County, Arizona, 2020

Abstract

Background Coronavirus disease 2019 (COVID-19) causes a range of illness severity. Mild illness has been reported, but whether illness severity correlates with infectivity is unknown. We describe the public health investigation of a mildly ill, nonhospitalized COVID-19 case who traveled to China. Methods The case was a Maricopa County resident with multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)–positive specimens collected on 22 January 2020. Contacts were persons exposed to the case on or after the day before case diagnostic specimen collection. Contacts were monitored for 14 days after last known exposure. High-risk contacts had close, prolonged case contact (≥ 10 minutes within 2 m). Medium-risk contacts wore all US Centers for Disease Control and Prevention–recommended personal protective equipment during interactions. Nasopharyngeal and oropharyngeal (NP/OP) specimens were collected from the case and high-risk contacts and tested for SARS-CoV-2. Results Paired case NP/OP specimens were collected for SARS-CoV-2 testing at 11 time points. In 8 pairs (73%), ≥ 1 specimen tested positive or indeterminate, and in 3 pairs (27%) both tested negative. Specimens collected 18 days after diagnosis tested positive. Sixteen contacts were identified; 11 (69%) had high-risk exposure, including 1 intimate contact, and 5 (31%) had medium-risk exposure. In total, 35 high-risk contact NP/OP specimens were collected for SARS-CoV-2 testing; all 35 pairs (100%) tested negative. Conclusions This report demonstrates that SARS-CoV-2 infection can cause mild illness and result in positive tests for up to 18 days after diagnosis, without evidence of transmission to close contacts. These data might inform public health strategies to manage individuals with asymptomatic infection or mild illness.

An Early Pandemic Analysis of SARS-CoV-2 Population Structure and Dynamics in Arizona

“…This substitution was, however, shared with 12 other genomes included in our analysis, all of which were sampled in China or Japan. This is consistent with infection of AZ1 occurring during documented travel to China (5).…”

“…Arizona's first confirmed case of COVID-19, the disease caused by SARS-CoV-2, was detected in late January 2020 in a student attending Arizona State University who had traveled to China (5). Extensive contact tracing and isolation led to zero additional reported cases stemming from this original case (AZ1).…”

Clinical and virologic characteristics of the first 12 patients with coronavirus disease 2019 (COVID-19) in the United States

“…All hospitalized patients were managed using standard, contact and airborne precautions, including eye protection. Median duration of fever was 9 d (range: [2][3][4][5][6][7][8][9][10][11]. Peak body temperature during hospitalization (range: 99.1-102.9 °F) occurred at a median of illness day 9 (range: 4-10) (Fig.…”

Features of Pathogens, Epidemiology, and Diagnosis of COVID-19 and Reliable Suggestion: Aiming to Solve the Confusion in Clinical Practice

“…Furthermore, some researchers compared the viral load of nasal mucosa in patients with symptomatic diagnosis and asymptomatic patients, and found it make no significant difference, thus this founding also corroborates the identity of the source of infection in asymptomatic or latent patients [75]. However, it is still unclear whether there is still potential ability for spreading infection after the symptoms disappear [76]. Scott, S. E. launch a community experiment reported a positive outcome up to 18 days of patients after the diagnosis of COVID-19, but mild or asymptomatic patients after non-intimate contact or using protective measures recommended by CDC will not be infected.…”