Characterization of SARS-CoV-2 RNA, antibodies, and neutralizing capacity in milk produced by women with COVID-19
Open accessPublished version of a preprint
Abstract
Background: It is not known whether SARS-CoV-2 can be transmitted from mother to infant during breastfeeding, and if so whether the benefits of breastfeeding outweigh this risk. This study was designed to evaluate 1) if SARS-CoV-2 RNA can be detected in milk and on the breast of infected women, 2) concentrations of milk-borne anti-SARS-CoV-2 antibodies, and 3) the capacity of milk to neutralize SARS-CoV-2 infectivity. Methods: We collected 37 milk samples and 70 breast swabs (before and after breast washing) from 18 women recently diagnosed with COVID-19. Samples were analyzed for SARS-CoV-2 RNA using RT-qPCR. Milk was also analyzed for IgA and IgG specific for the nucleocapsid protein, receptor binding domain (RBD), S2 subunit of the spike protein of SARS-CoV-2, as well as 2 seasonal coronaviruses using ELISA; and for its ability to neutralize SARS-CoV-2. Results: We did not detect SARS-CoV-2 RNA in any milk sample. In contrast, SARS-CoV-2 RNA was detected on several breast swabs, although only one was considered conclusive. All milk contained SARS-CoV-2-specific IgA and IgG, and levels of anti-RBD IgA correlated with SARS-CoV-2 neutralization. Strong correlations between levels of IgA and IgG to SARS-CoV-2 and seasonal coronaviruses were noted. Conclusions: Our data do not support maternal-to-child transmission of SARS-CoV-2 via milk; however, risk of transmission via breast skin should be further evaluated. Importantly, milk produced by infected mothers is a source of anti-SARS-CoV-2 IgA and IgG and neutralizes SARS-CoV-2 activity. These results support recommendations to continue breastfeeding during mild-to-moderate maternal COVID-19 illness.
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IgA dominates breastmilk profiles in natural SARS-CoV-2 infection.
“In contrast, IgA dominates breastmilk profiles in natural SARS-CoV-2 infection 22 .”
From Coronavirus disease 2019 vaccine response in pregnant and lactating women: a cohort study (2021) · cites this paper as [22]
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Cites
Breastfeeding and the Use of Human Milk
Breastfeeding, S. O. (2005) · PEDIATRICS · doi:10.1542/peds.2004-2491 · Cited by 5,310 · see citing works
Breastfeeding and the use of human milk
BREASTFEEDING, S. O., Eidelman, A. I., Schanler, R. J., Johnston, M., Landers, S., Noble, L., Szucs, K., & Viehmann, L. (2012) · Pediatrics · doi:10.1542/peds.2011-3552 · Cited by 4,357 · see citing works
Chen, H., Guo, J., Wang, C., Luo, F., Yu, X. B., Zhang, W., Li, J., Zhao, D., Xu, D., Gong, Q., et al. (2020) · The Lancet · doi:10.1016/s0140-6736(20)30360-3 · Cited by 3,921 · see citing works
Clinical and immunological assessment of asymptomatic SARS-CoV-2 infections
Long, Q.-X., Tang, X.-J., Shi, Q.-L., Li, Q., Deng, H.-J., Yuan, J., Hu, J.-L., Xu, W., Zhang, Y., Lv, F.-J., et al. (2020) · Nature Medicine · doi:10.1038/s41591-020-0965-6 · Cited by 2,686 · see citing works
Viral dynamics in mild and severe cases of COVID-19
Liu, Y., Yan, L.-M., Wan, L., Xiang, T.-X., Le, A., Liu, J.-M., Peiris, M., Poon, L. L. M., & Zhang, W. (2020) · The Lancet Infectious Diseases · doi:10.1016/s1473-3099(20)30232-2 · Cited by 1,727 · see citing works
Enhanced isolation of SARS-CoV-2 by TMPRSS2-expressing cells
Matsuyama, S., Nao, N., Shirato, K., Kawase, M., Saito, S., Takayama, I., Nagata, N., Sekizuka, T., Katoh, H., Kato, F., et al. (2020) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.2002589117 · Cited by 1,414 · see citing works
Delayed Breastfeeding Initiation Increases Risk of Neonatal Mortality
Edmond, K. M., Zandoh, C., QUIGLEY, M. A., Amenga‐Etego, S., Owusu‐Agyei, S., & Kirkwood, B. R. (2006) · PEDIATRICS · doi:10.1542/peds.2005-1496 · Cited by 1,057 · see citing works
Rapid Decay of Anti–SARS-CoV-2 Antibodies in Persons with Mild Covid-19
Ibarrondo, F. J., Fulcher, J. A., Goodman-Meza, D., Elliott, J., Hofmann, C., Hausner, M. A., Ferbas, K. G., Tobin, N. H., Aldrovandi, G. M., & Yang, O. O. (2020) · New England Journal of Medicine · doi:10.1056/nejmc2025179 · Cited by 1,021 · see citing works
Lu, X., Wang, L., Sakthivel, S. K., Whitaker, B., Murray, J., Kamili, S., Lynch, B., Malapati, L., Burke, S. A., Harcourt, J. L., et al. (2020) · Emerging infectious diseases · doi:10.3201/eid2608.201246 · Cited by 679 · see citing works
Detection of SARS-CoV-2 in human breastmilk
Groß, R. M., Conzelmann, C., Müller, J. A., Stenger, S., Steinhart, K., Kirchhoff, F., & Münch, J. (2020) · The Lancet · doi:10.1016/s0140-6736(20)31181-8 · Cited by 376 · see citing works
Fan, C., Di, L., Fang, C., Li, C., Wang, M., Liu, Y., Bao, Y., Sun, Y., Huang, J., Guo, Y., et al. (2020) · Clinical Infectious Diseases · doi:10.1093/cid/ciaa226 · Cited by 374 · see citing works
Kirtsman, M., Diambomba, Y., Poutanen, S. M., Malinowski, A. K., Vlachodimitropoulou, E., Parks, W. T., Erdman, L. K., Morris, S. K., & Shah, P. S. (2020) · Canadian Medical Association Journal · doi:10.1503/cmaj.200821 · Cited by 334 · see citing works
† (2016) · The Lancet Global Health · doi:10.1016/s2214-109x(16)00040-1 · Cited by 316 · see citing works
The risks of not breastfeeding for mothers and infants.
Stuebe, A. M. (2009) · PubMed · Cited by 304 · see citing works
Robust and Specific Secretory IgA Against SARS-CoV-2 Detected in Human Milk
Fox, A., Marino, J. A., Amanat, F., et al. (2020) · iScience · doi:10.1016/j.isci.2020.101735 · Cited by 292 · see citing works
Evaluation for SARS-CoV-2 in Breast Milk From 18 Infected Women
Chambers, C., Krogstad, P. A., Bertrand, K. A., Contreras, D. A., Tobin, N. H., Bode, L., & Aldrovandi, G. M. (2020) · JAMA · doi:10.1001/jama.2020.15580 · Cited by 264 · see citing works
Cui, Y., Tian, M., Huang, D., Wang, X., Huang, Y., Fan, L., Wang, L., Chen, Y., Liu, W., Zhang, K., et al. (2020) · The Journal of Infectious Diseases · doi:10.1093/infdis/jiaa113 · Cited by 230 · see citing works
Nguyen-Contant, P., Embong, A. K., Kanagaiah, P., Chaves, F. A., Yang, H., Branche, A. R., Topham, D. J., & Sangster, M. Y. (2020) · mBio · doi:10.1128/mbio.01991-20 · Cited by 204 · see citing works
Self-citationSerologic Cross-Reactivity of SARS-CoV-2 with Endemic and Seasonal Betacoronaviruses
Hicks, J., Klumpp-Thomas, C. A., Kalish, H. R., Shunmugavel, A., Mehalko, J. L., Denson, J.-P., Snead, K., Drew, M. R., Corbett, K. S., Graham, B. S., et al. (2021) · Journal of Clinical Immunology · doi:10.1007/s10875-021-00997-6 · Cited by 186 · see citing works
Neonatal Late Onset Infection with Severe Acute Respiratory Syndrome Coronavirus 2
Costa, S., Buonsenso, D., Sanguinetti, M., et al. (2020) · American Journal of Perinatology · doi:10.1055/s-0040-1710541 · Cited by 176 · see citing works
Parker, L. A., Sullivan, S. E., Krueger, C., et al. (2015) · Breastfeeding Medicine · doi:10.1089/bfm.2014.0089 · Cited by 172 · see citing works
Immunologic Factors in Human Milk: The Effects of Gestational Age and Pasteurization
Köenig, Á., Diniz, E. M. D. A., Barbosa, S. F. C., et al. (2005) · Journal of Human Lactation · doi:10.1177/0890334405280652 · Cited by 171 · see citing works
SARS‐CoV‐2 and human milk: What is the evidence?
Lackey, K. A., Pace, R. M., Williams, J. E., Bode, L., Donovan, S. M., Järvinen, K. M., Seppo, A., Raiten, D. J., Meehan, C. L., McGuire, M. A., et al. (2020) · Maternal and Child Nutrition · doi:10.1111/mcn.13032 · Cited by 163 · see citing works
Self-citationAntibodies in the breast milk of a maternal woman with COVID-19
Dong, Y., Chi, X., Huang, H., et al. (2020) · Emerging Microbes & Infections · doi:10.1080/22221751.2020.1780952 · Cited by 145 · see citing works
Breastmilk RNA viral load in HIV-infected South African women
Willumsen, J. F., Filteau, S., Coutsoudis, A., et al. (2003) · AIDS · doi:10.1097/00002030-200302140-00015 · Cited by 124 · see citing works
Filteau, S., Lietz, Mulokozi, G., Bilotta, S., Henry, C. J., & Tomkins (1999) · Immunology · doi:10.1046/j.1365-2567.1999.00834.x · Cited by 113 · see citing works
Tam, P. C. K., Ly, K. M., Kernich, M. L., Spurrier, N. J., Lawrence, D., Gordon, D., & Tucker, E. C. (2020) · Clinical Infectious Diseases · doi:10.1093/cid/ciaa673 · Cited by 108 · see citing works
Fouda, G. G., Yates, N. L., Pollara, J., Shen, X., Overman, G., Mahlokozera, T., Wilks, A. B., Kang, H. H., Salazar-Gonzalez, J. F., Salazar, M. G., et al. (2011) · Journal of Virology · doi:10.1128/jvi.05174-11 · Cited by 95 · see citing works
Breastfeeding Risk from Detectable Severe Acute Respiratory Syndrome Coronavirus 2 in Breastmilk
Zhu, C., Liu, W., Su, H., et al. (2020) · Journal of Infection · doi:10.1016/j.jinf.2020.06.001 · Cited by 75 · see citing works
Goldsmith, S. J., Dickson, J. S., Barnhart, H. M., Toledo, R. T., & Eitenmiller, R. R. (1983) · Journal of Food Protection · doi:10.4315/0362-028x-46.1.4 · Cited by 74 · see citing works
Mazur, N. I., Horsley, N., Englund, J. A., Nederend, M., Magaret, A., Kumar, A., Jacobino, S. R., de Haan, C. A. M., Khatry, S. K., LeClerq, S. C., et al. (2018) · The Journal of Infectious Diseases · doi:10.1093/infdis/jiy477 · Cited by 70 · see citing works
Quataert, S. A., Rittenhouse‐Olson, K., Kirch, C. S., et al. (2004) · Clinical and Vaccine Immunology · doi:10.1128/cdli.11.6.1064-1069.2004 · Cited by 68 · see citing works
Delayed Breastfeeding Initiation Is Associated with Infant Morbidity
Smith, E. R., Locks, L. M., Manji, K. P., et al. (2017) · The Journal of Pediatrics · doi:10.1016/j.jpeds.2017.08.069 · Cited by 64 · see citing works
Pollara, J., McGuire, E., Fouda, G. G., et al. (2015) · Journal of Virology · doi:10.1128/jvi.01560-15 · Cited by 61 · see citing works
Tesini, B. L., Kanagaiah, P., Wang, J., Hahn, M. A., Halliley, J. L., Chaves, F. A., Nguyen, P. Q. T., Nogales, A., DeDiego, M. L., Anderson, C., et al. (2019) · Journal of Virology · doi:10.1128/jvi.00169-19 · Cited by 51 · see citing works
Self-citationCharacteristics of pregnant patients with COVID-19 and liver injury
Deng, G., Zeng, F., Zhang, L., Chen, H., Chen, X., & Yin, M. (2020) · Journal of Hepatology · doi:10.1016/j.jhep.2020.06.022 · Cited by 41 · see citing works
Li, C., Solomons, N. W., Scott, M. E., & Koski, K. G. (2017) · Journal of Trace Elements in Medicine and Biology · doi:10.1016/j.jtemb.2017.11.010 · Cited by 32 · see citing works
Tsutsumi, H., Honjo, T., Nagai, K., et al. (1989) · Journal of Clinical Microbiology · doi:10.1128/jcm.27.9.1949-1951.1989 · Cited by 23 · see citing works
Järvinen, K. M., Wang, J., Seppo, A., & Zand, M. S. (2018) · F1000Research · doi:10.12688/f1000research.16717.1 · Cited by 12 · see citing works
Self-citationJärvinen, K. M., Wang, J., Seppo, A., & Zand, M. S. (2019) · F1000Research · doi:10.12688/f1000research.16717.2 · Cited by 10 · see citing works
Self-citation
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Research works printed but not linked: 1
- [24]Fox A, Marino J, Amanat F, Evidence of a significant secretory-IgA-dominant SARS-CoV-2 immune response in human milk following recovery from COVID-19. medRxiv 2020; 2020.05.04.20089995. preprint.
Cited by
Sorted by citations
Coronavirus disease 2019 vaccine response in pregnant and lactating women: a cohort study
Gray, K. J., Bordt, E. A., Atyeo, C., Deriso, E., Akinwunmi, B., Young, N., Baez, A. M., Shook, L. L., Cvrk, D., James, K., et al. (2021) · American Journal of Obstetrics and Gynecology · doi:10.1016/j.ajog.2021.03.023 · Cited by 699 · see citing works
Immunogenicity of COVID-19 mRNA vaccines in pregnant and lactating women
Collier, A.-R. Y., McMahan, K., Yu, J., Tostanoski, L. H., Aguayo, R., Ansel, J., Chandrashekar, A., Patel, S., Apraku Bondzie, E., Sellers, D., et al. (2021) · JAMA · doi:10.1001/jama.2021.7563 · Cited by 397 · see citing works
SARS-CoV-2–Specific Antibodies in Breast Milk After COVID-19 Vaccination of Breastfeeding Women
Perl, S. H., Uzan-Yulzari, A., Klainer, H., Asiskovich, L., Youngster, M., Rinott, E., & Youngster, I. (2021) · JAMA · doi:10.1001/jama.2021.5782 · Cited by 285 · see citing works
Raiten, D. J., Combs, G. F., Steiber, A. L., & Bremer, A. A. (2021) · Advances in Nutrition · doi:10.1093/advances/nmab046 · Cited by 33 · see citing works
- Authors
- Pace, R. M., Williams, J. E., Järvinen, K. M., Belfort, M. B., Pace, C. D. W., Lackey, K. A., Gogel, A. C., Nguyen-Contant, P., Kanagaiah, P., Fitzgerald, T., Ferri, R., Young, B., Rosen-Carole, C., Diaz, N., Meehan, C. L., Caffé, B., Sangster, M. Y., Topham, D., McGuire, M. A., Seppo, A., & McGuire, M. K.
- Affiliations
- University of Idaho (US)
- University of Rochester Medicine (US)
- Brigham and Women's Hospital (US)
- David H. Smith Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, USA
- Washington State University (US)
- Margaret Ritchie School of Family and Consumer Sciences, University of Idaho, Moscow, Idaho, USA
- Corresponding author
- Seppo, Antti
- ORCID
- Venue
- mBio
- Publisher
- American Society for Microbiology
- Published
- 2021-02-23
- Volume
- 12
- Issue
- 1
- ISSN
- 2150-7511 (ISSN-L)
- 2161-2129
- PMC
- PMC7523143
- OpenAlex
- W3127200741
- Cited by
- 315
- References
- 40
- Citations by year
- 2026: 10 · 2025: 10 · 2024: 35 · 2023: 45 · 2022: 106 · 2021: 102 · 2020: 6 · 2014: 1
- FWCI
- 22.78
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- mBio (publishedVersion, cc-by)
- medRxiv (acceptedVersion, cc-by-nc-nd)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- PubMed Central (submittedVersion, cc-by-nc-nd)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- Washington State University Health Equity Research Center
- University of Idaho Agricultural Experiment Station
- HHS | National Institutes of Health (R01 HD092297-03, U01 AI131344-04S1)
- Bill and Melinda Gates Foundation
- Topics
- Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
- Health Sciences › Medicine › Obstetrics and Gynecology › COVID-19 Impact on Reproduction
- Health Sciences › Nursing › Nutrition and Dietetics › Infant Nutrition and Health
- Keywords
- SARS-CoV-2, COVID-19 pandemic, breast milk, mother-to-child transmission, breastfeeding, SARS-CoV-2 antibodies, IgA, IgG, neutralizing antibodies, SARS-CoV-2 RNA, maternal infection, infant immunity
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