Immunocompromised Children, Young Adults at Greater Risk for Prolonged COVID-19 Infection

Although prolonged COVID-19 infections are rare, even in children or young adults with compromised immunity, it could have public health implications.

Children and young adults with compromised immune systems may experience a more prolonged infection with COVID-19, and this extended infection may increase the incidence of mutations, according to researchers from Children’s Hospital Los Angeles.

Most patients with COVID-19 are infectious for approximately 10 days after first showing symptoms, according to the researchers. In the new study, investigators described 2 children and a young adult with acute lymphoblastic leukemia who tested positive for SARS-CoV-2 for months. According to the study, this represents the first report of prolonged infection in a pediatric or young adult population.

“It’s significant that these patients continued to have active symptoms and active infections for such a long time,” said lead author Jennifer Dien Bard, PhD, director of the Clinical Microbiology and Virology Laboratory at Children’s Hospital Los Angeles, in the press release. “The large number of pediatric and adult patients receiving cancer therapy and being actively screened for the virus leads us to conclude that this is a rare occurrence but one that could have public health implications.”

In addition to the risk of prolonged infection, the researchers suggested that longer infections could result in the development of viral mutations. SARS-CoV-2 mutates about once or twice a month, according to Dien Bard. When it replicates, it copies its genetic code, although the viruses sometimes mutate. According to the study, most of these mutations have no effect on how the virus behaves or on the disease it causes, but some may result in the virus acting differently.

For example, the B.1.1.7 SARS-CoV-2 variant has 17 mutations and is believed to be more infectious than other virus variants. Dien Bard noted that there is some evidence to suggest the B.1.1.7 variant may have originated in a person who was immunocompromised and consistently infected with SARS-CoV-2. It is still important to note, however, that months-long infections are rare even in immunocompromised patients.

“We have had many other immunocompromised patients who have not experienced these prolonged infections, but it’s something to be aware of, and hospitals may want to consider changing infection control policies to address this particular special population,” Dien Bard concluded in the press release.


Virus that Causes COVID-19 May Result in Prolonged Infection for Children and Young Adults with Compromised Immune Systems [news release]. Children’s Hospital Los Angeles; April 28, 2021. Accessed May 4, 2021.