We reviewed articles that provide information about neonatal infection with COVID-19 to find the best method of approaching to these neonates. Based on this study:
Infection of newborns with COVID-19 is possible in three ways:
1) Being born to mothers diagnosed with COVID-19 (maternal-fetal or maternal-neonatal)
2) Having close contact with the family member’s infection with COVID-19
3) Living in or travelling to the pandemic area (
2,
20,
21).
There are a few data about the possibility of mother-fetal transmission in COVID-19, but there is no definite evidence for vertical transmission.
In our review, all samples (amniotic fluid, cord blood, breast milk) were negative for COVID-19, but three neonates had elevated COVID-19 IgM antibodies. The maternal-fetal transfer passage is not proven yet, because, most infants meet full protective measures.
Clinical manifestation of infected neonates might be nonspecific, such as temperature instability, apnea, respiratory distress, GI symptoms, and hypotension, the predominant symptom being mild respiratory symptoms. Term neonates are usually asymptomatic (
31).
In our review, 56.5% of neonates were asymptomatic, in other reviews, the most common symptoms were: shortness of breath, tachypnea, cough, apnea, temperature instability, and tachycardia.
The incubation period in a neonate is between 3 and 7 days on average, with one day as the shortest and 14 days the longest (
4,
15). In our review, seven neonates showed symptoms after the first week of life.
Radiographic findings in neonates may be likely to show pneumonia, and in the chest CT scan (computed tomography), we may see subpleural lesions with localized inflammatory infiltration (
15,
33). The most common findings on chest radiographs and chest CT in our review were: thickened lung texture, mild pulmonary infection, ground glass (respiratory distress syndrome), high density modular, and patchy shadow under pleura.
In our review, one neonate had leukopenia, and three neonates had lymphopenia. Three neonates had thrombocytopenia. Five neonates had elevated CPK (creatine phosphokinase). One neonate had elevated CRP, and two had elevated procalcitonin. Other studies emphasized that in infants and children, unlike adults, elevated inflammatory markers are less common, CRP does not increase in neonates, and leukopenia and lymphopenia are less common (
3,
5,
9,
15). In Iran, leukopenia, and lymphopenia (infant < 3000 and children < 2000) are reported just in 30% of children suffering COVID-19 (
32). However, our data about neonates are minimal.
Symptomatic and supportive care and treatment of complications are the primary therapeutic measures for COVID-19. These include oxygen therapy, maintenance of water-electrolytes, acid-base balance, inhalations, and nutritional support. For a newborn with severe acute respiratory distress syndrome, high-dose surfactant, NO (nitric oxide), high-frequency oscillatory ventilation, and ECMO (extracorporeal membrane lung) is implemented. Experts do not recommend antiviral drugs. Antibiotics are suggested just for cases with clinical or paraclinical signs of bacterial superinfection. One study in Iran recommended corticosteroids and interferon-alpha 2b nebulization for critically ill neonates; intravenous immunoglobulin is also suggested although there is no evidence supporting the effectiveness of gamma globulin, interferon, or hormone therapy (
9,
32).
In our review, one neonate in the USA received hydroxychloroquine, and in one case in Iran, oseltamivir was prescribed. In four neonates antibiotics were prescribed because of the possibility of superinfection. In one study in China IVIG (intravenous immunoglobulin) and a corticosteroid was prescribed for an ill neonate.
Three neonates underwent mechanical ventilation, and in the others, noninvasive ventilation and oxygen therapy were initiated. According to studies, preferred ventilation mode in the neonate with COVID-19 is high-frequency oscillatory ventilation.
Some local protocols recommend cesarean section, but there is no clear benefit of delivery via cesarean in women with COVID-19 infection (
17). 66.6% of neonates were born via cesarean section because of routine indications in our review.
Strict prevention strategies in neonates born to suspected or confirmed COVID-19 mothers decrease infection in neonates. We have to maintain contact and droplet precaution in mother and neonate, and separate them for 14 days after birth (
3,
17,
21). In our review, in all but for five neonates protective care was taken at birth.
Although protective care was utilized in most infants in our study, it should be noticed that this study only regarded infected neonates and has not reviewed the vertical transmission rate. Numerous studies have reviewed mother-neonate transmission of COVID-19 and have shown the effect of protecting care in the prevention of neonatal infection. Therefore, it is reasonable that protective measures should be provided in all deliveries in which the mother is infected with COVID-19. In three neonates, the father was also affected. Therefore, the isolation of the newborn should be eligible for all family members.
All neonates born to suspected/confirmed COVID-19 mothers get first nasopharyngeal swab collected within 24 hours after birth or as soon as mother’s test is reported positive, the second swab has to differentiate between surface contamination and persistent viral shedding. Anyway, the nasopharyngeal swab’s “positive detection rate” is less than 50% (
9,
20,
21). Since the incubation period in newborns is unknown, one concern is that testing a single sample may not be sufficient, and a negative result does not rule out infection, so additional tests are required (
26).
In our review, the primary test for COVID-19 was positive in 15 neonates. In 3 neonates, the second test was positive, although the initial test was negative. This confirms that a single test may not suffice, and a negative result does not rule out infection, so it is necessary to perform a second test in neonates with high suspicion.
Despite low morbidity and mortality rate in neonates with COVID-19, the transmission of the disease from them to other family members is very likely. Therefore, to reduce transmission rate, we have to pay close attention to this age group.