Oral vaccine via dental bacteria and emitted peptides to prevent COVID-19 infection

A pharmaceutical composition to prevent transmission of a pathogen, the pharmaceutical composition comprising:

• a) genetically modified commensal bacteria capable of colonizing an oral and/or nasal mucosa of a subject;
• and
• b) pharmaceutical excipients,
• wherein the genetically modified commensal bacteria are from mouth and/or nose commensal bacteria modified by transgenic technology to comprise genes encoding small peptides, such that the bacteria transcribe, translate, produce, and secrete the small peptides expressed in situ at the oral and/or nasal mucosa of the subject and which neutralize the pathogen,
• wherein the small peptides are selected from the group consisting of SEQ ID NO:
• 1, SEQ ID NO:
• 2, SEQ ID NO:
• 3, SEQ ID NO:
• 4, SEQ ID NO:
• 5, SEQ ID NO:
• 6, SEQ ID NO:
• 7, SEQ ID NO:
• 8, SEQ ID NO:
• 9, and SEQ ID NO:
• 10,
• wherein the transgenic technology is used to modify commensal bacteria to produce transgenic bacteria to obtain the genetically modified commensal bacteria by introducing a recombinant vector into the commensal bacteria, the recombinant vector comprising genes encoding the small peptides inserted into a vector to add said genes that are transcribed and translated for recombinant expression in the genetically modified commensal bacteria to produce and secrete the small peptides from the genetically modified commensal bacteria in situ at the oral and/or nasal mucosa,
• wherein the genetically modified commensal bacteria deliver the small peptides in situ at the oral and/or nasal mucosa of the subject,
• wherein the subject is a mammal,
• wherein the pathogen is a coronavirus,
• wherein the coronavirus comprises severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2),
• wherein the pharmaceutical excipients comprise stabilizers, buffers, cryoprotectants, or other agents formulated to aid the oral and/or nasal administration of the pharmaceutical composition, and
• wherein the genetically modified commensal bacteria carrying the added genes encoding the small peptides provide an effective and easy administration by means of an easy-to-administer pharmaceutical composition for neutralization of the pathogen to prevent transmission of the pathogen in situ at the oral and/or nasal mucosa of the subject.