4th COVID-19 Vaccine Now Available For At-Risk U.S. Citizens

COVID-19 news^[1] now sees the availability of an additional primary dose of an mRNA COVID-19 vaccine for immunocompromised individuals with moderately or severely compromised immune systems. 

As the 4th COVID shot^[2], this additional primary dose is not to be confused with the booster shot. Rather, is intended to improve the individual’s response to their vaccine primary series. 

As available data^[3] suggests, COVID-19 vaccines may be less effective in immunocompromised populations, who are then at increased risk of severe COVID-19. 

Apart from this, recent reflection on the pandemic reveals a weakening of immunity response in general, even in non-immunocompromised individuals. 

New variants continue to bring new challenges in building immunity and reducing infection rates, which currently are seeing a surge in the Omicron variant. With this, global measures and health officials have and will continue to provide recommendations to help address rising needs.

Who Is At-Risk And Eligible To Recieve The 4th Shot? 

According to the Centers For Disease Control And Prevention^[2] (CDC), at-risk patients are those who are severely or moderately immunocompromised. Patients who match the following criteria are at risk and now are eligible for their fourth primary shot:

• Active treatment for solid tumor and hematologic malignancies and have been receiving active cancer treatment for cancers of the blood. Low-response rates within this group of cancer patients range from 2% to 36%^[3]. Low-responsive rates for those with hematological malignancy ranges from 14 to 61%^[3]. 
• Have received a solid-organ transplant or, taking immunosuppressive therapy or immunosuppressive medicine. Recent literature reviews^[3] show that immunosuppressive therapies associated with dialysis patients show a non-responder, a lower response status, or lower antibody levels.
• Have received a Chimeric antigen receptor or hematopoietic stem cell transplant within two years, and or taking immunosuppression medicine or undergoing immunosuppression therapy
• Have moderate or severe primary immunodeficiency, for example, DiGeorge syndrome or Wiskott-Aldrich syndrome
• Have advanced or untreated HIV infection
• Are undergoing active treatment with high-dose corticosteroids (i.e., ≥20mg prednisone or equivalent per day), alkylating agents, antimetabolites, transplant-related immunosuppressive drugs, cancer chemotherapeutic agents classified as severely immunosuppressive, tumor-necrosis factor (TNF) blockers, and other biologic agents that are immunosuppressive or immunomodulatory.

These key identifiers, and other criteria^[3], follow numerous academic studies, group studies, literature reviews, and research performed within the immunosuppressed populations: 

• Cancer
• Hematological malignancy 
• Solid Organ transplantation
• Allogeneic stem cell transplantation
• Autoimmune systemic disease
• Autoimmune organ-specific disease
• Inflammatory bowel disease
• Sarcoidosis
• Autoinflammatory disease
• Multiple sclerosis
• Neuromyelitis Optica spectrum disease
• Chronic Kidney Disease
• HIV Infection 
• Congenital Immunodeficiency 

Adding to this, those who have undergone a kidney transplant are considered eligible. A published medical review^[4] notes that a high percentage of transplant recipients who are exposed to the virus will become infected. This fact is combined with the possibility of a donor-derived infection influenced by exposure of the donor, the infectivity of individuals during the incubation period, and infection by asymptomatic people. 

Also affecting the risk of donor transmission is the extent and duration of viremia and the viability of the virus within specific blood or organ compartments. 

Consult Your Health Practitioner Should Uncertainty Of Eligibility Arise

As recommended by CDC^[2] the level of risk associated with immune suppression should factor in medical conditions, COVID-19 community transmission, personal risk of infection, and potential response to the vaccine.  Those with suppressed immunity should consult their health practitioner should they be concerned about their eligibility. 

New Guidelines For Vaccine Efficacy Must Be Followed

As expressed by numerous news sites^[5], all immunocompromised patients should receive this fourth shot. To avoid prolonged illness, should one become infected, due to the inability to make antibodies^[3], receiving the 4th primary shot is recommended giving the improved capacity to clear the virus. 

While no confirmed timeline to receive this additional shot after the primary series is known yet, eligible patients can expect to receive this 4th shot between five and 12 months after their third shot. 

For now, it is reported that people without antibodies are the ones at the highest risk^[6], and health officials and authorities should push health and safety measures for those who have low or non-detectable immune responses.

---