How COVID-19 is Affecting Neonates in the United States

Three years ago in late 2019, the first case of what we now call COVID-19 was diagnosed.  Several months later, a global pandemic was declared, with the Novel Coronavirus disease 2019 (COVID-19) spreading quickly across the planet¹.  From the scarcity of knowledge and more questions than answers, our collective understanding of how COVID-19 affects different populations slowly grows.  But information about the effect of COVID-19 in neonates has been slower to trickle in, partly due to the (thankfully) lower overall incidence in this population².  A recent study published in Pediatrics helps to close that gap. 

The study published in Pediatrics (October 2022) was a cross-sectional study, retrospectively reviewing medical records to provide insight into the effect of COVID-19 on neonates in the United States².  In this case, neonates were defined as babies less than 28 days of age. Their findings support what those of us working with neonatal patients anecdotally experience, that neonatal COVID-19 is uncommon (relative to other age brackets) and that severe illness is rare.

How often do neonates get COVID-19?

The study used a population database containing medical information from more than 100 health systems (the Cerner Real-Word Database) to determine that out of over a million neonatal health encounters, 918 were diagnosed with COVID-192.   Of these neonates, 71 (7.7%) had a severe illness, and the remainder were mild or asymptomatic. 

Most babies were not diagnosed in the immediate post-natal period².  The median time to diagnosis was 14.5 days, with only one baby diagnosed less than 12 hours from birth.  It is widely thought that vertical transmission (from mother to baby during pregnancy, labour, or delivery) is rare, a notion supported by this study.    

Asymptomatic or mild COVID-19

Most neonates were asymptomatic or had mild signs of infection (tachypnea and fever being the most common symptoms)².  The median length of stay for these babies was only one day.  About 7% of these babies received antibiotics and, less commonly, received analgesia or antivirals.  

Severe COVID-19 illness

Neonates were determined to have severe COVID-19 if they had signs in at least 2 out of these three categories²:

• Clinical symptoms (fever, apnea, cough, tachypnea, respiratory distress, oxygen requirements, vomiting, diarrhea)
• Abnormal laboratory findings (low white blood cells, low lymphocytes or raised CRP)
• Abnormal chest x-ray (such as findings consistent with pneumonia).

Babies with severe COVID-19 not surprisingly required more support during their illness².  Treatment included respiratory support (mostly non-invasive), analgesia, antibiotics and uncommonly anticoagulants, corticosteroids and antiarrhythmics.  Other therapies also included Remdesivir (RNA polymerase inhibitor which stops replication of the virus³) in 2.8% of those with severe COVID-19 and less commonly COVID-19 convalescent plasma (CCP) (plasma collected from a previously positive patient to provide antibodies⁴)in 1.4% of cases.

Prematurity and other congenital issues matter.

Not surprisingly, those neonates at most risk of severe disease were:

• Premature infants and low birth weight infants
• Infants with congenital abnormalities
• Infants with congenital heart defects

This remains consistent with what we know about other respiratory illnesses, such as respiratory syncytial virus (RSV).  Whereas any baby can get RSV, it is the smallest or those with congenital heart defects or other anomalies are at the most significant risk for morbidity⁵. 

Does race, ethnicity or geography make a difference?

A majority of the neonates with COVID-19 were Hispanic/Latinx (36.7%) or non-Hispanic white (27%), followed by non-Hispanic Black or African American (7.5%), non-Hispanic American Indian or Alaskan Native (1.7%0 and the smallest group, non-Hispanic Asian American (1%)².

The highest incidence of neonates with COVID-19 was identified in Massachusetts, Maine, New Hampshire, New Jersey, Rhode Island, and Vermont (8.1% of total cases), while the lowest rate was in New York and Pennsylvania².  The region with the most severe COVID-19 cases correlated with the region reporting the lowest cumulative vaccination rates (Alabama, Florida, Georgia, Mississippi, and Tennessee).   That being said, the study demonstrates that no area is immune, with cases reported across the country.  

Most neonates were better in a matter of days.

In general, the length of stay for neonates with COVID-19 was relatively short compared to those with the highest COVID-19-related morbidity and mortality (I.e. elderly, immunocompromised⁶).  Most neonates identified had mild or asymptomatic COVID-19 and were home within a day or two (median one day)².  Even those with severe illness had a median stay of only five days.  The study reported 93.6% being discharged home, 1% being transferred to another hospital, one death and the remainder (5.2%) as “unknown.” 

Bottom line

COVID-19 illness in neonates remains rare, and most babies diagnosed with COVID-19 in the first month of life will have mild disease or no symptoms at all.  Some babies with severe COVID-19 needed respiratory support and other interventions, illustrating that no age group is entirely unaffected by significant COVID-19-related illness.   Neonatal and pediatric care teams need to remain alert for signs of COVID-19 and be cautious not to presume that those diagnosed will sail through.  This study can support a reassuring message to parents that severe illness and poor outcomes are exceedingly rare in infants, and most infants will have mild, if any, illness.  Education about preventing disease transmission for this respiratory virus and others should remain forefront in discharge education for newborns.

References:

1 World Health Organization: Coronavirus disease (COVID-19): pandemic

2 Epidemiology of Neonatal COVID-19 in the United States, Pediatrics, October 2022

3 NIH, COVID-19 Treatment Guidelines: Remdesivr

4 NIH, COVID-10 Treatment Guidelines: COVID-19 convalescent plasma

5 Center for Disease Control and Prevention: Respiratory Syncytial Virus

6 Center for Disease Control and Prevention: Excess deaths associated with COVID-19