A retrospective review of young infants with community-acquired SARS-CoV-2 hospitalized in neonatal intensive care

Research background: describing SARS-CoV-2 in neonates

The community spread of the novel coronavirus 2019 (SARS-CoV-2, the virus that causes COVID-19) and how it impacts adults has been well researched, and more is being discovered about the virus’ impact during the perinatal period and on older children. There is very limited research describing how SARS-CoV-2 impacts neonates, a population with unique immunity considerations.

Researchers in the Department of Neonatology at Children’s Hospital Colorado sought to the describe the demographic, epidemiologic and clinical features of a cohort of neonates with SARS-CoV-2.

Research methods: identifying cases of SARS-CoV-2 in neonatal patients

The early retrospective study identified patients who were admitted to the Neonatal Intensive Care Unit (NICU) at Children’s Colorado and tested positive for SARS-CoV-2. Study information came from the hospital’s medical record system. The SARS-CoV-2 diagnosis was confirmed by real-time polymerase chain reaction (RT-PCR) assay of nasopharyngeal swabs, and patients were tested for other viruses and bacteria by RT-PCR in the collected specimens.

Research results: demographic, epidemiological and clinical features of three neonates with SARS-CoV-2

Three neonates were identified with confirmed SARS-CoV-2 from March 28 to April 1, 2020. Of the infants identified:

• All were tested for SARS-CoV-2 when presented to the emergency department, and weren’t tested again
• Two were male
• All were healthy, born between 39 and 40 weeks’ gestation
• Two were exclusively receiving breastmilk
• Symptoms began between 16 and 31 days old
• Two had known ill contacts with upper respiratory infections
• One had no known ill contacts, but recently visited the pediatrician

All infants presented to the Emergency Department at Children’s Colorado with the following symptoms:

• Fever
• Rhinorrhea
• Mild hypoxia with desaturations on room air to 80 to 90%

Before being admitted to the NICU, the youngest infant experienced tachycardia, systemic vasodilation and bilateral conjunctivitis, and required saline fluid resuscitation in the emergency department.

While in the NICU, all infants:

• Required supplemental oxygen via nasal cannula to maintain >90% oxygen saturation
• Experienced neutropenia (one was admitted with neutropenia; two became neutropenic)
• Showed low lung volumes with hazy opacities without areas of focal consolidation in chest radiographs
• Tested within normal limits for hematocrit, platelet count, liver function test, lactate and blood gas
• Tested negative for bacterial cultures and discontinued antimicrobials within 24 to 36 hours
• Experienced no serious complications from infection

Upon admission to the NICU, the youngest infant had lymphopenia and a mildly elevated C-reactive protein, but both resolved by the time of discharge.

The length of stay for all infants ranged from 77 to 81 hours, and all were discharged after being fever-free for at least 24 hours.

Research discussion: learning from young infants diagnosed with SARS-CoV-2

The study describes three of the youngest patients to be diagnosed with SARS-CoV-2 in the United States. Little is known about SARS-CoV-2 in older neonates, and as the outbreak extends, additional understanding will become even more important.

Historically, human coronaviruses were first identified in the 1960s, and account for 5% to 7% of all hospitalizations of U.S. children. While most children experience a very mild or asymptomatic illness, it is different in neonates.

Neonates may experience two different modes of disease, similar to other RNA viruses:

• Virus may be transmitted around delivery, often presents with pneumonia or sepsis-like syndrome in up to 10% of neonates
  • Early onset, severe symptoms in first week of life were likely due to lack of serotype-specific neutralizing antibody (mothers did not have immunity)
• Infants in late neonatal period may be more vulnerable
  • They may develop moderate illness likely due to immature B-cells and biased Th2 responses

The patients featured in the study met previously published diagnosis requirements for SARS-CoV-2. They were healthy, full-term infants prior to the infection and presented with fever and underwent protocols to rule out sepsis. Their disease course was mild to moderate with short hospital stays, which is consistent with previous literature.

While more is being learned about this population, study authors recommend:

• Caregivers should wear masks and wash their hands before coming into contact with neonates to limit community spread of SARS-CoV-2 to this potentially vulnerable population
• Healthy babies should be isolated from positive family member cases