Can Antibodies from COVID-19 Be Transmitted Through Saliva?

The question of whether antibodies from the novel coronavirus (SARS-CoV-2) can be transmitted through saliva has been a subject of considerable discussion and speculation. Understanding the dynamics of antibody transmission is crucial for public health strategies and personal protective measures.

Understanding the Nature of Antigens and Antibodies

Antibodies and antigens play fundamental roles in the immune response to pathogens. Antigens are foreign substances that trigger the immune system to produce antibodies. Typically, when the immune system encounters an antigen, it responds by producing antibodies that can neutralize or destroy the antigen. Conversely, antibodies are proteins produced by the immune system to specifically bind to and neutralize antigens.

However, the role of saliva in transmitting these antibodies is a complex issue. In this article, we explore the current scientific understanding of whether antibodies can indeed be transmitted through saliva and what implications this might have for public health.

Current Evidence and Scientific Consensus

According to the current scientific consensus, the physiological process does not support the transmission of antibodies through saliva in a clinically significant manner.

Firstly, saliva contains trace amounts of antibodies, but these antibodies, while present, are not likely to provide meaningful protection to another individual. The immune system views these antibodies as foreign and may neutralize or ignore them. This is a common mechanism to protect the body from self-reactivity, ensuring that the immune response does not turn against the body’s own tissues.

Secondly, while breast milk may contain antibodies beneficial for the development of an infant's immune system, transmitting these antibodies through saliva is not a reliable method of conferring immunity to an individual. Although saliva can transmit trace viral loads, these amounts may be insufficient to initiate an infection or provide immunity. Moreover, the presence of a viral load does not guarantee transmission, and the benefits of breastfeeding should be weighed against potential risks.

Current recommendations from public health agencies advise against suspending breastfeeding due to the recognized benefits, despite the potential risk of viral transmission. At the same time, it is important to acknowledge that simply being in close proximity to an infected individual or engaging in activities like kissing can increase the risk of infection.

Individual Variation and Inconsistency

It is also worth noting that the presence of antibodies in the saliva varies among individuals. Some people produce antibodies in their saliva, while others do not. This variability complicates attempts to make broad statements about the potential transmission of antibodies through this route.

Moreover, some research suggests that the mechanism for antibody transmission through saliva might be inconsistent and inefficient. For certain pathogens, such as the herpes simplex virus, saliva has been shown to contain antibodies. However, the evidence for such transmission is not strong for the novel coronavirus (SARS-CoV-2). The amount of virus in saliva, even from an infected individual, is generally low and not likely to result in significant transmission.

Conclusion

The transmission of antibodies from the novel coronavirus through saliva is not supported by current scientific evidence. Saliva may contain trace amounts of antibodies, but these are not likely to provide meaningful protection or confer immunity to others. Breastfeeding remains a critical aspect of infant nutrition and development, and the potential risk of viral transmission should be weighed against the substantial benefits of continued breastfeeding.

Public health measures should continue to focus on mitigating the risk of viral transmission through other routes, such as close contact, kissing, and sharing personal items. The variability in individual antibody presence in saliva also underscores the need for a comprehensive approach to managing the risk of viral transmission.