In the current case series study, 10 neonates with documented COVID-19, using the positive PCR for the virus, are described. Besides, their concurrent symptoms, such as fever and respiratory symptoms (as the most common symptoms (50%)) are reported. Consistent with the results of the present study, there are studies that mentioned fever as one of the most common symptoms of the disease in children and neonates (
10). However, in the present study, in all of the investigated cases, the duration of fever was short. Severe respiratory distress was detected just in one patient, which led to the death of the patient. This finding is in agreement with other published reports on children infected with COVID-19, such as the study by De Rose et al. (
4), who reported that acute and severe respiratory symptoms related to coronavirus presented a children-sparing pattern. Neurological symptoms, such as seizure, loss of consciousness, GI problems, and other symptoms, which were reported in adult or children cases, were not observed in most of our patients. In a report by De Bernardo et al. (
13), the clinical presentations of neonates with COVID-19 in 25 different published case reports are compared.
Similar to our cases, De Bernardo et al. (
13) reported problems related to the GI, such as vomiting, in 4 (out of 25) cases. Although in the mentioned report 6 neonates were asymptomatic, in the present study, we did not find asymptomatic patients, and all were susceptible neonates born to mothers with a positive PCR test and all of our patients had symptoms of the disease even the mild manifestations, besides the positive nasopharyngeal or nasal PCR test, which confirmed the COVID-19.
Regarding the low probability of false-positive PCR results for COVID-19, it seems that the less severity of disease in our patients confirmed the results of other case reports of neonatal COVID-19 with mild signs and symptoms of the disease.
Having a family history of the disease was detected just in one of our patients, in which confirmed COVID-19 led to the death of the mother, and in another case, the mother was suspected of the disease. This finding confirmed the disease transmission from asymptomatic patients to our neonates or horizontal spread of the disease during labor at the hospital with the presentation of symptoms in neonates after some days of incubation periods. Contrary to our case series, in a report by De Bernardo et al. (
13), of 25 neonatal COVID-19 cases, just one case had no positive history of the disease in mother or father and family.
In a case report by Mirahmadizadeh et al. (
14), an 11-day- old neonate with severe watery diarrhea and vomiting, leukocytosis, and positive PCR for COVID-19 is presented. The patient was discharged six days after diagnosis with good condition. None of our patients had GI symptoms, such as diarrhea or vomiting. In another case report by Dumpa et al. (
15) a 22-day-old neonate is presented with fever and poor feeding and positive PCR result for COVID-19 with no abnormal laboratory and radiologic finding, which are similar to most of our patients. This patient had a full recovery and was discharged two days after admission (
15).
The most common findings of chest X-ray or lung CT scan in COVID-19 are ground-glass appearance alone or in combination with pulmonary consolidations (
16). Although all of our patients were subjected to chest X-ray, just one preterm infant with a history of respiratory distress syndrome had an abnormal chest X-ray in accordance with HMD at the first time and opacity and ground-glass appearance in the right lung after 4 days (patient number 5), and another patient (case 8) with abnormal radiology according to ground-glass appearance, due to COVID-19, had the abnormal findings in the chest X-ray. In a case report performed in China by Wang et al. (
17), a term neonate with vertical transmission of COVID-19 is reported. Despite the lack of respiratory symptoms, three lung CT scans of the patient showed abnormalities, such as high-density nodular shadow under the pleura and patchy density of the right lungs. Fortunately, the neonate was discharged in good condition (
17).
In children with COVID-19, lymphopenia is reported in 75% of patients, but in some Iranian reports, lymphopenia was detected in 35% of patients (
11). Lymphopenia, as an early biomarker of COVID-19 that also indicates its severity, was not detected in our patients. A recent report indicated the poor outcome of patients with COVID-19 and lymphopenia as well as the increased mortality rate in these patients (
18). In a case report by Farsi et al., in a triplet premature pregnancy-related to a mother with symptomatic COVID-19 and positive PCR result, one twin had positive PCR for COVID-19, and the other babies, despite the negative PCR result, had symptoms of the disease. They also had a white lung with a ground-glass appearance in the chest X-ray; the lymphopenia was not detected in the complete blood cell (CBC) of all patients (
19).
The cardiac involvement by COVID-19 is reported in some published case reports, such as the report by Amiraskari et al. (
20), which presented a neonate with myocarditis and respiratory distress initiated at birth from a mother with COVID-19 infection and labor at 36 weeks of gestation. Treatment with mechanical ventilation, endotracheal surfactant, milrinone, and dobutamine saved the patient. However, unfortunately, the mother of the patient died by COVID-19 on the fourth day of delivery (
20). In our case series study, there was no cardiac involvement in all 9 patients. Just one neonate had a cardiac murmur in physical examination (case number 8). As echocardiography was not available, we could not confirm cardiac involvement by echocardiography.
Fortunately, the overall outcome of our patients was good with full recovery and early discharge for continuing quarantine at home, except for one patient who died (patient number 8). Despite providing supportive care and mechanical ventilation, he died on the fourth day of admission. As our sample size is small, judgment about the exact outcome of COVID1-9 in the neonatal period is not possible. Besides, as few case series studies have investigated COVID-19 in neonates, our case series adds new information about this new infection in neonatal periods. The current study had limitations, including the lack of chest CTS of nine patients as well as the absence of PCR results of parents of patients.
3.1. Conclusions
According to our cases, clinical manifestations, as well as laboratory and radiologic findings of neonates infected with COVID-19, are mild. Since having a family history of COVID-19 was not obvious in most of our patients, it seems that, during the COVID-19 pandemic, asymptomatic parents, siblings, or caregivers can be a main source of infection for neonates.