The purpose of this observational research study is to better understand immune responses to vaccines against viruses (influenza or SARS-CoV2). The goal is to determine any differences in immune responses to vaccines in uninjured people and in people living with spinal cord injuries, who are typically at increased risk of infections.

The purpose of this research study is to measure a person's immune response to a vaccine by measuring types of circulating white blood cells (WBC) and the substances they produce in blood, including antibodies, proteins, and ribonucleic acids (the body's genetic blueprint for making proteins).

The research will study two populations: uninjured people and people living with spinal cord injury (SCI), who are often at increased risk of infections. We will measure and observe over time any differences in immune responses to vaccines between those groups or among people with SCI according to their injury severity or level.

The overall goal of this study is to increase knowledge of immune responses to vaccination against influenza virus that causes the flu, and to the SARS-CoV-2 virus that causes COVID-19. There is currently a lack of information about what influences individual responses to vaccines and why people with SCI are at typically at increased risk of infection. Results from this study may teach us how to improve vaccination strategies and other ways to fight infections in uninjured people and in people with SCI

Inclusion Criteria

SCI Participant Inclusion Criteria: To be eligible for prospective enrollment, participants are required to meet the following inclusion criteria:

• 18-89 years old with traumatic SCI
• initial traumatic SCI >/=1 year from enrollment (DOD funded study)
• initial traumatic SCI <1 year from enrollment (non-DOD funded pilot study)
• American Spinal Injury Association (ASIA) classification grade A-D
• Neurological Injury Level C1-T10
• Demonstrate capacity to provide informed consent using the "teach back" method to verify understanding and appreciation of study objectives and procedures.

Exclusion Criteria

To be eligible for prospective enrollment, SCI participants are required to not meet the following exclusion criteria:

• Stage III-IV pressure ulcers
• Cancer, chemotherapy, neutropenia
• Pregnancy or lactation
• No known SCI
• Autoimmune disease
• Pre-existing neurological disease
• History of dementia
• Any other condition that would compromise their ability to provide informed consent
• Any other condition that a study physician feels would preclude participation or be contraindicated

Uninjured Control Group:

Inclusion Criteria

Uninjured Control Participant Inclusion Criteria: To be eligible for prospective enrollment, participants are required to meet the following inclusion criteria:

• 18-89 years old without traumatic SCI
• Demonstrate capacity to provide informed consent using the "teach back" method to verify understanding and appreciation of study objectives and procedures.

Exclusion Criteria

To be eligible for prospective enrollment, uninjured control participants are required to not meet the following exclusion criteria:

• Cancer, chemotherapy, neutropenia
• Pregnancy or lactation
• Autoimmune disease
• Pre-existing neurological disease
• History of dementia
• Any other condition that would compromise their ability to provide informed consent
• Any other condition that a study physician feels would preclude participation or be contraindicated

Participants will be adults (ages 18-89 years old) with SCI or who are uninjured controls who are electing to receiving flu or COVID-19 vaccines to promote their health.