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Because the mother with SARS-CoV-2 RNA detected in human milk sample is not breastfeeding, the risk of contagion from the infant to the mother is eliminated. This is first case with SARS-CoV-2 RNA detected in human milk of mother who does not breastfeed her infant.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a extremely infectious disease, and the current outbreak has been declared by WHO as a global public health threatening. Researches have showed that transmission of SARS-CoV-2 is mainly from person to person via airborne droplets .1,2 However, it can be throught skin contac, faecal-oral transmission, and oculer surface contact.3-5 Gold standard diagnostic method of SARS-CoV-2 is the virus to be detected in nasopharyngeal swabs by a reverse transcription real-time PCR (RT-qPCR). 1,2 The virus also can be detected in bronchoalveolar-lavage fluid, sputum, saliva, faces, and urine. 6,7 It is unclear whether SARS-CoV-2 can be shed into human milk and transmitted to a child via breastfeeding.
Here we investigated SARS-CoV-2 RNA in breast-milk samples of three mothers with SARS-CoV-2 and their infants. All mothers were informed about the study and gave informed consent. Necessary permission was obtained from the health authority of our country (Republic of Turkey Ministry of Health).
All mothers lives in the east of Turkey. At different times they were admitted to our hospital. For the mothers, computed tomography (CT) scan was not shown any abnormal finding. CT scans were not performed to infants.
The mother 1 with 22-day newborn (infant 1) ise a 24-year-old woman. She had brought a healthy baby through normal vaginal delivery. The newborn and mother did not have any health problems during and after delivery. She brought the infant to the emergency room due to high fever (38,3oC). The infant’s throat swab was positive for SARS-CoV-2. The mother has sore throat, fatigue, and light cough, with a body temperature of 36.6 oC. Blood tests of the mother revealed normal. Her vital signs were stable with oxygen saturation of 97% in room air. Her chest CT scan don’t showed any abnormal findings. Because the infant’s throat swab was positive for SARS-CoV-2, the test was also applied to the mother too. Also, her throat swab was positive. The mother 1 and her infant were isolated in the same room of the hospital.The mother 1 was evaluated as SARS-CoV-2 and received hydroxychloroquine (2x400mg [first day], 2x200 mg for 4 days [oral,5days in total]), azithromycin (1x500mg [first day] ,1x250 mg for 4 days [oral,5 days in total]),and Enoksaparin sodyum (2x 0,6ml,sc) according to the interim national guide. On the 5th day of hospitalization, throat swab sample of mother and baby for SARS-CoV-2 were negative. On the 6th day of hospitalization, breast milk was collected with pumps and sterod into a sterile container. On the same day, it was detected SARS-CoV-2 RNA in milk sample from mother 1. Because the nipple was sticky, the mother could not breastfeeding. Because the mother is not breastfeeding, the risk of contagion from the infant to the mother is eliminated. The mother 1 and her infant were discharged as healthy on the 7th day of hospitalization. Moreover, the mother 1 was reexamined 14 days after discharge, and no viral RNA was detected in her breastmilk.
The mother 2 with 36-day infant (infant 2) ise a 26-year-old woman. She had given birth with cesarean section. The newborn was healthy. She has a history of bipolar disorder for 6 years and has been treated with oral drugs. She did not use medicines for bipolar disorder during pregnancy. She had breastfed her newborn for 4 weeks after birth. She had used drug (Lithuril, Quetiapine, Haloperidol dekanoat) for bipolar disorder. She was not breastfeeding for the past week because of using drugs. She was admitted to the emergency room due to her psychiatric complaints on the 36th postpartum. Because of cought and sore throat, the throat swab sample for SARS-CoV-2 RNA was positive. By contrast, throat swab of infant 2 was negative. Chest CT scan and all laboratory parameters(cbc,crp,etc) were normal. Other findings of both mother 2 and infant 2 are shown in table 1. She was discharged as healthy on the 6th day of hospitalization.
The mother 3 with 120-day infant (infant 3) ise a 26-year-old woman. She had brought a healthy baby through normal vaginal delivery. The mother 3 and her infant did not have any health problems during and after delivery. She was breastfeeding. She was admitted to the emergency room due to her complaints (sore throat, cought). Chest CT scan and all laboratory parameters(cbc,crp,etc) were normal. Her throat swab sampled for SARS-CoV-2 was positive. Throat swab of infant 3 was negative. Other findings of both mother 3 and infant 3 are shown in table1. During the 14-day isolation, the mother 3 breastfeed her infant by wearing a surgical mask. During this period, no health problems developed in the infant 3. After the 14-day izolation, the throat swab of both mother 3 and infant 3 for SARS-CoV-2 were negative.
For breast milk collection, iodine was used to disinfect all patient’s breast. Breast milk was collected with pumps and sterod into a sterile container. On the day of taking the samples, SARS-CoV-2 RNA was examined in all breast milk samples. Following admission, two breast milk samples from Mother 2 and 3 tested negative. By contrast, SARS-CoV-2 RNA was detected in milk from mother 1. Additionally, throat swabs of infant 1 was positive. All test results of the SARS-CoV-2 RNA for mothers and infnats were shown in table 1.
All throat swab and breast milk samples were evaluated in our center microbiology laboratory and by the same expert team.The presence of SARS-CoV-2 RNA in the breast milk of the patient was investigated with a reverse transcription real-time PCR (RT-qPCR) method with Bio-Speedy RT-qPCR kit (Bioeksen R&D Technologies Ltd., Turkey) targeting the RNA-dependent RNA polymerase (RdRp) gene of the virus. The viral RNA was extracted with Bio-Speedy vNAT kit (Bioeksen R & D Technologies Ltd., Turkey) and amplification was performed in Rotor-Gene Q 5plex HRM device (Qiagen, Belgium).
Human milk has numerous advantages for newborns, containing inactive transmission of antibodies against several microbial diseases.8 To date, in the literature, the presence of SARS-CoV-2 RNA has only been detected in the breast milk of two mothers with SARS-CoV-2. One of these case was reported by Groß Ret al. in the lancet.9 The RT-qPCR for SARS-CoV-2 was positive in the swab of this mother’s newborn. Because this mother was breastfeeding her newborn, the virus could be contaminated to the breast through the secretions of the newborn. The other case was reported by Wu Y at al .10 The RT-qPCR for SARS-CoV-2 was not done in the swab of this mother’s newborn.10 While RT-qPCR was positive in human milk of one(mother 1) of our cases, it was found negative in the others (mother 2 and 3). RT-qPCR of SARS-CoV-2 was positive in swabs of infant 1. Other mothers except the mother 1 were breastfeeding until the diagnosis of SARS-CoV-2. Also,during the 14-day isolation, the mother 3 breastfeed her infant by wearing a surgical mask. During this period, no health problems developed in the infant 3. After the 14-day izolation, the throat swab of both mother 3 and infant 3 for SARS-CoV-2 were negative.
To the best of our knowledge, this (mother 1 ) is third case with SARS-CoV-2 RNA detected in human milk. On the other hand, this is first case with SARS-CoV-2 RNA detected in human milk of mother who does not breastfeed her infant(infant 1).
In a study by Liu W et al , ten breast milk samples from mothers were obtained after their first lactation and tested for SARS-CoV-2 RT-qPCR with negative results.11 In our study, in one of the 5 milk samples taken from the mothers, RT-q PCR for SARS-CoV-2 was positive.The existing data indicates that SARS-CoV-2 can be rare transmitted through breastmilk.
As in the example of mother 3 in our study, we think that the benefits of breastfeeding may outweigh the risk of SARS-CoV-2 infection in infants. In our cases, the mother 3 breastfeed her infant and SARS-CoV-2 was not transmitted from mother to infnat during the mother’s illness. Therefore, as recommended by the world health organization12, we recommend that mothers with SARS-CoV-2 breastfeed their infants on condition that they wear a surgical mask. Also, more studies are needed on whether SARS-CoV-2 is excreted in breast milk and whether it is transmitted to the infant through breast milk.
Acknowledgements: We would like to thank Yusuf Yakupogulları (M.D., Prof.),and Barıs Otlu (PhD.,Prof.) from the microbiology department ,and Yasar Bayındır (M.D.,Prof.) from department of infection diseases. Also, we thank all the medical staff members involved in treating those women and their infants.
Conflict of Interest. The authors have no conflict of interest to declare. This work has not been supported by grant from any funding agency in the public, commercial, or not-for-profit sectors.