A novel coronavirus, the causative agent of the current pandemic of viral respiratory illness and pneumonia, was first identified in Wuhan, Hubei, China. The disease has been given the name, coronavirus disease 2019 (COVID-19). The virus at last report has spread to more than 100 countries. Much of what we suspect about this virus comes from work on other severe coronavirus respiratory disease outbreaks – Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS). MERS-CoV was a viral respiratory disease, first reported in Saudi Arabia, that was identified in more than 27 additional countries. The disease was characterized by severe acute respiratory illness, including fever, cough, and shortness of breath. Among 2,499 cases, only two patients tested positive for MERS-CoV in the United States. SARS-CoV also caused a severe viral respiratory illness. SARS was first recognized in Asia in 2003 and was subsequently reported in approximately 25 countries. The last case reported was in 2004.
As of March 13, there are 137,066 cases worldwide of COVID-19 and 1,701 in the United States, according to the John Hopkins University Coronavirus COVID-19 resource center.
What about children?
The remarkable observation is how few seriously ill children have been identified in the face of global spread. Unlike the H1N1 influenza epidemic of 2009, where older adults were relatively spared and children were a major target population, COVID-19 appears to be relatively infrequent in children or too mild to come to diagnosis, to date. Specifically, among China’s first approximately 44,000 cases, less than 2% were identified in children less than 20 years of age, and severe disease was uncommon with no deaths in children less than 10 years of age reported. One child, 13 months of age, with acute respiratory distress syndrome and septic shock was reported in China. According to the Centers for Disease Control and Prevention webcast , children present with fever in about 50% of cases, cough, fatigue, and subsequently some (3%-30%) progress to shortness of breath. Some children and adults have presented with gastrointestinal disease initially. Viral RNA has been detected in respiratory secretions, blood, and stool of affected children; however, the samples were not cultured for virus so whether stool is a potential source for transmission is unclear. In adults, the disease appears to be most severe – with development of pneumonia – in the second week of illness. In both children and adults, the chest x-ray findings are an interstitial pneumonitis, ground glass appearance, and/or patchy infiltrates.
Are some children at greater risk? Are children the source of community transmission? Will children become a greater part of the disease pattern as further cases are identified and further testing is available? We cannot answer many of these questions about COVID-19 in children as yet, but as you are aware, data are accumulating daily, and the Centers for Disease Control and Prevention and the National Institutes of Health are providing regular updates.
A report from China gave us some idea about community transmission and infection risk for children. The Shenzhen CDC identified 391 COVID-19 cases and 1,286 close contacts. Household contacts and those persons traveling with a case of the virus were at highest risk of acquisition. The secondary attack rates within households was 15%; children were as likely to become infected as adults (medRxiv preprint. 2020. doi: 10.1101/2020.03.03.20028423).