Immune Response of Neonates Born to Mothers Infected With SARS-CoV-2

IMPORTANCE

Although several studies have provided information on short-term clinical outcomes in children with perinatal exposure to SARS-CoV-2, data on the immune response in the first months of life among newborns exposed to the virus in utero are lacking.

OBJECTIVE

To characterize systemic and mucosal antibody production during the first 2 months of life among infants who were born to mothers infected with SARS-CoV-2.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study enrolled 28 pregnant women who tested positive for SARS-CoV-2 infection and who gave birth at Policlinico Umberto I in Rome, Italy, from November 2020 to May 2021, and their newborns. Maternal and neonatal systemic immune responses were investigated by detecting spike-specific antibodies in serum, and the mucosal immune response was assessed by measuring specific antibodies in maternal breastmilk and infant saliva 48 hours after delivery and 2 months later.

EXPOSURES

Maternal infection with SARS-CoV-2 in late pregnancy.

MAIN OUTCOMES AND MEASURES

The systemic immune response was evaluated by the detection of SARS-CoV-2 IgG and IgA antibodies and receptor binding domain-specific IgM antibodies in maternal and neonatal serum. The mucosal immune response was assessed by measuring spike-specific antibodies in breastmilk and in infant saliva, and the presence of antigen-antibody spike IgA immune complexes was investigated in breastmilk samples. All antibodies were detected using an enzyme-linked immunosorbent assay.

RESULTS

In total, 28 mother-infant dyads (mean [SD] maternal age, 31.8 [6.4] years; mean [SD] gestational age, 38.1 [2.3] weeks; 18 [60%] male infants) were enrolled at delivery, and 21 dyads completed the study at 2 months' follow-up. Because maternal infection was recent in all cases, transplacental transfer of virus spike-specific IgG antibodies occurred in only 1 infant. One case of potential vertical transmission and 1 case of horizontal infection were observed. Virus spike protein-specific salivary IgA antibodies were significantly increased (P = .01) in infants fed breastmilk (0.99 arbitrary units [AU]; IQR, 0.39-1.68 AU) vs infants fed an exclusive formula diet (0.16 AU; IQR, 0.02-0.83 AU). Maternal milk contained IgA spike immune complexes at 48 hours (0.53 AU; IQR, 0.25-0.39 AU) and at 2 months (0.09 AU; IQR, 0.03-0.17 AU) and may have functioned as specific stimuli for the infant mucosal immune response.

CONCLUSIONS AND RELEVANCE

In this cohort study, SARS-CoV-2 spike-specific IgA antibodies were detected in infant saliva, which may partly explain why newborns are resistant to SARS-CoV-2 infection. Mothers infected in the peripartum period appear to not only passively protect the newborn via breastmilk secretory IgA but also actively stimulate and train the neonatal immune system via breastmilk immune complexes.

Reproductive patterns and energy management strategies of females of the fiddler crab Leptuca uruguayensis with short reproductive seasons

Reproduction is a costly process that depends on the management of available resources. Here, we aimed to understand the energetic strategies of females of the fiddler crab Leptuca uruguayensis (Nobili, 1901) in a population with short reproductive seasons. For this, we developed an integrated approach to recognize the brooding time, spawning pattern modulated by female size, number of spawns per female, and content of reserves in the ovary and hepatopancreas. Based on the condition of the ovary and hepatopancreas, the reproductive season was divided into three periods. In each of these periods, it was possible to record a spawning event, which was mainly represented by large females. Most of the females had one spawn during the breeding season, and only large females had two spawns, with an interval of approximately 2 months. We propose that L. uruguayensis presents a mixed capital–income breeding strategy associated with the female size and period of the reproductive season. We conclude that large females make the greatest reproductive effort for the population because they can have two spawns, whereas medium-sized and small females make a low contribution because they are still investing energy in somatic growth to increase fecundity in the next reproductive season.

Liver Involvement in SARS-CoV-2 Vertically Infected Newborn: A Case Report

Neonatal SARS-CoV-2 infection can occur antenatally, peripartum, or postnatally. In the newborn, clinical manifestations may vary including fever and respiratory, gastrointestinal and neurological symptoms. Most commonly, they are subclinical. We herein present a case of vertical transmission of SARS-CoV-2 presenting with liver injury, characterized by an increase in serum transaminases.

Gait analysis in bladder exstrophy patients with and without pelvic osteotomy: a controlled experimental study

BACKGROUND

The role of bony pelvic anomalies in bladder exstrophy is long established and has generated many papers addressing walking problems. Biomechanical studies and kinematic gait analysis were performed on very young children.

AIM

A direct kinetic gait evaluation has never been performed, nor has the effect of pelvis dimorphism on the upper body been studied.

DESIGN

Controlled experimental study.

SETTING

Outpatients were studied at the time of periodic follow up.

POPULATION

Nineteen patients with bladder exstrophy, age 14±8 years, and twenty-five healthy control participants, age 15±8 years, were enrolled in the present gait analysis study.

METHODS

Clinical evaluation and standard gait analysis were performed.

RESULTS

Gait analysis deviations between exstrophy patients and controls and between patients that received pelvic osteotomy (OT--6 patients) and those that did not (no-OT--13 patients) were analyzed. Bladder exstrophy significantly affects kinematics and kinetics of trunk, spine, pelvis, knee and foot; in particular: in OT, trunk retroversion, pelvic retroversion and rotation, hip adduction angle and moment, knee flexion and its maximum power during loading response increased, whereas in no-OT, spine angle, pelvic posterior tilt, hip extension, and the external rotation of the foot progression angle increased. All the kinetics parameters analyzed in the study showed lower values in the patient group than in controls.

CONCLUSION

. Walking in patients with bladder exstrophy is accomplished by retroversion of the pelvis and deviations mainly in the spine angle in no-OT and in knee flexion in OT.

CLINICAL REHABILITATION IMPACT

Gait analysis was shown to be an effective tool for the detection of walking deviations that should be identified early, prompting rehabilitative treatment in order to prevent spine and knee diseases.

Cow's milk and the emergence of group B streptococcal disease in newborn babies

BACKGROUND

Group B streptococcus (GBS), the most significant cause of neonatal bacterial sepsis, is thought to have emerged in the 1960s. GBS also causes mastitis in cows, and there is indirect evidence that human GBS is derived from a bovine ancestor.

OBJECTIVE

A major change in the collection of milk from farms, using bulk tanks rather than churns, occurred in the 1960s. We sought to define the temporal relationship between this change in farming and the emergence of GBS neonatal disease.

METHODS

We searched PubMed for reports of GBS disease from 1930 until 1980 to more exactly determine the time of emergence of neonatal infection and supported this data with UK hospital admission statistics for GBS infections. We identified the dates of the change from churns to bulk tanks by searching the internet and books for information on the history of milk transportation, farming and milk collection in the UK.

RESULTS

There are no PubMed reports of neonatal GBS disease between 1930 and 1950, and reports from the UK only emerged in the mid-1960s, confirming the notion that GBS neonatal infection was a newly emergent disease in the 1960s. No national data on hospital admissions are available around this time, but the Oxford Record Linkage Study, with admission data available for Oxford from 1968, showed no cases of neonatal disease until 1974. Cow's milk collection in the UK switched to bulk tank between 1960 and 1979, and publications relating to GBS disease emerged soon after.

CONCLUSIONS

There is a temporal relationship between the emergence of neonatal GBS disease reports in the UK in the 1960s and a change in cow's milk collection. This finding may be a temporal coincidence or may add support to the notion that human GBS was historically derived from a bovine ancestor.

Comparison between rectal and infrared skin temperature in the newborn

The reliability of measurement of body temperature using a new infrared skin thermometer was evaluated in 107 newborns. The use of the device was associated with low operator-related variability and acceptable limits of agreement with the temperature measured with a rectal mercury thermometer. Use of the infrared skin thermometer is a comfortable and reliable way of measurement of body temperature in newborns.