Table 2.

RNA analysis of SARS-CoV-2 in human breastmilk.

Ref.	Year	Type of Study	Sample	Results	Conclusions
[54]	2020	Observational, prospective study	7	Of the seven breastmilk samples collected from infected mothers, all were negative for SARS-CoV-2 by RT-PCR.	Breastmilk was not a source of SARS-CoV-2 transmission. Expressing breastmilk manually, when direct breastfeeding is not possible, appears to be a safe way to feed newborns of mothers who are infected with COVID-19.
[55]	2020	Observational, prospective study	10	Of the ten breastmilk samples collected from infected mothers, all were negative for SARS-CoV-2 by RT-PCR.	Breastmilk was not a source of SARS-CoV-2 transmission. The most important strategies in preventing neonatal SARS-CoV-2 infection are to prevent maternal infection and reduce the possibility of neonatal exposure to the virus.
[56]	2020	Observational study	6	Of the six breastmilk samples collected from infected mothers, all were negative for SARS-CoV-2 by RT-PCR.	SARS-CoV-2 was not found in breastmilk.
[57]	2020	A case report	2	Of the two breastmilk samples collected from infected mothers, all were negative for SARS-CoV-2 by RT-PCR.	Health workers must protect, motivate and encourage breastfeeding. The most likely mother-child transmission is through respiratory droplets.
[58]	2020	A case report	2	Of the 11 breastmilk samples that were collected from two infected mothers (four samples from Mother 1, seven samples from Mother 2), the four samples from Mother 1 were negative and the first four samples from Mother 2 were positive while the last three were negative for SARS-CoV-2 by RT-PCR.	Whether the neonate was infected through breastmilk or other modes of transmission is unknown. Further studies are needed.
[59]	2020	A case report	5	Of the 11 breastmilk samples that were collected from five infected mothers (one sample from Mother 1, two samples from Mother 2, two samples from Mother 3, two samples from Mother 4, one sample from Mother 5), only two samples from Mother 3 were positive for SARS-CoV-2 by RT-PCR.	Conclusions are limited due to the small sample size.
[60]	2020	A case report	1	The neonate was fed breastmilk in the mother’s room and did not become infected.	Encourage breastfeeding and safe room sharing.
[61]	2020	A retrospective case series	22	The neonates were fed breastmilk (20/22) and infant formula (2/22). Nine of the 11 symptomatic mothers were isolated. No infants were infected.	Breastfeed with precautions, after maternal isolation: donor human breastmilk or infant formula until breastfeeding is resumed.
[62]	2020	A case report	1	The breastmilk sample collected from the infected mother was negative for SARS-CoV-2 by RT-PCR. The neonate was fed breastmilk after isolation from the mother.	Breastfeeding after isolation and negative test. Feed the neonate pumped breastmilk during isolation.
[63]	2020	A case report	1	The breastmilk sample collected from the infected mother was positive for SARS-CoV-2 by RT-PCR. Breastfeeding was discontinued after detection of the virus in breastmilk.	Decision of whether to breastfeed should be taken by parents and doctor.
[64]	2020	A case report	1	The breastmilk sample collected from the infected mother was negative for SARS-CoV-2 by RT-PCR. The neonate was breastfed breastmilk pumped from the mother and separated from their mother. The neonate was not infected.	SARS-CoV-2 is rarely transmitted through breastmilk. In addition, there may be an induction of passive immunity from IgG.
[65]	2020	A case report	1	Breastfeeding was discontinued after the mother’s diagnosis and the infant was separated. The neonate was not infected.	Temporarily stop breastfeeding.
[66]	2020	A case report	1	The breastmilk sample collected from the infected mother was negative for SARS-CoV-2 by RT-PCR. The neonate was fed pumped breastmilk directly after isolation from the mother.	Breastfeed cautiously when virus is not found in breastmilk.
[67]	2020	A case report	1	The breastmilk sample collected from the infected mother was negative for SARS-CoV-2 by RT-PCR.	Transmission of the infection from mother to child is very unlikely.
[68]	2020	A case report	1	The breastmilk sample collected from the infected mother was negative for SARS-CoV-2 by RT-PCR. The neonate was breastfed.	Breastfeeding is safe.
[69]	2020	A case report	1	The breastmilk sample collected from the infected mother was positive for SARS-CoV-2 by RT-PCR. Direct breastfeeding was stopped and pumped breastmilk was given when it was confirmed that the infant had been infected with COVID-19.	Breastfeeding should be continued in infected nursing babies. There were no adverse effects. Finding SARS-CoV-2 RNA in the breastmilk sample does not indicate a viable virus.
[70]	2020	A case report	1	Infant formula was given to the neonate and direct breastfeeding was resumed after the baby tested positive.	Encourage breastfeeding and safe room sharing when both mother and infant are infected.
[71]	2020	A case report	1	The breastmilk sample collected from the infected mother was positive for SARS-CoV-2 by RT-PCR. The neonate was breastfed as they were also infected.	More studies are needed to identify transmission routes.
[72]	2020	A case report	1	The breastmilk sample collected from the infected mother was positive for SARS-CoV-2 by RT-PCR. The neonate was fed infant formula.	Breastfeeding can have a protective effect on the infant.
[73]	2020	A case report	1	The breastmilk sample collected from the infected mother was negative for SARS-CoV-2 by RT-PCR. The neonate was breastfed pumped breastmilk from the mother and separated from their mother.	Do not breastfeed when both mother and infant are infected.
[74]	2020	A case series	2	The two breastmilk samples collected from infected mothers were negative for SARS-CoV-2 by RT-PCR. The neonates were fed infant formula. One of the two neonates was separated from their mother.	There is a low risk of vertical transmission through breastmilk. Furthermore, it plays a potentially protective role for passive antibodies.
[75]	2020	Observational, retrospective study	36	Thirty-two of the 36 neonates were breastfed, both directly and pumped. Nine of the 36 neonates were separated from their mother. Thirty-four of 36 neonates tested negative for SARS-CoV-2 and two tested positive.	Support of direct breastfeeding or fed with pumped breastmilk with precautions.
[76]	2020	Prospective, multicentre study	61	Forty-five of 62 neonates were directly breastfed, 13 were directly breastfed and fed infant formula, three were fed infant formula, and one was directly breastfed and fed pumped breastmilk. Eleven of 62 neonates were separated from their mother. No neonate was positive for SARS-CoV-2 at birth and two from 62 were positive at seven and 20 days of life, respectively.	Encourage breastfeeding and room sharing with good conditions when mothers are infected.
[77]	2020	Transversal, retrospective study	45	Thirty-one of 33 neonates were breastfed. Thirty-three of 45 neonates were not separated from the mother. Forty-two of 45 neonates tested negative for SARS-CoV-2.	Encourage breastfeeding and appropriate safe room sharing.
[78]	2020	Collaborative, observational, prospective study	14	Of the 14 breastmilk samples collected from 14 infected mothers, 13 were negative for SARS-CoV-2 by RT-PCR. Eleven of 12 neonates were exclusively breastfed. Neonates were not separated from mothers. Four of 12 neonates tested positive for SARS-CoV-2.	Encourage breastfeeding or feeding with pumped breastmilk (when in isolation) regardless of results with appropriate precautions.
[79]	2020	A case report	One (not infected)	The neonate tested positive for SARS-CoV-2. They were exclusively breastfed and not separated from the mother	More studies are needed to identify transmission routes.