The Four Ws of the Fourth Dose COVID-19 Vaccines: Why, Who, When and What

Autor: Ka-Wa Khong, Ruiqi Zhang, Ivan Fan-Ngai Hung
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Vaccines, Vol 10, Iss 11, p 1924 (2022)
Druh dokumentu: article
ISSN: 2076-393X
47922311
DOI: 10.3390/vaccines10111924
Popis: With the emergence of SARS-CoV-2 variants, vaccine breakthrough is a major public health concern. With evidence of reduced neutralizing antibody activity against Omicron variants and fading antibody level after the third-dose booster vaccine, there are suggestions of a fourth-dose booster vaccine. In this review, the benefits of a fourth-dose booster is evaluated from four perspectives, including the effectiveness of the booster dose against virus variants (Why), susceptible groups of individuals who may benefit from additional booster dose (Who), selection of vaccine platforms to better enhance immunity (What) and appropriate intervals between the third and fourth booster dose (When). In summary, a fourth dose can temporarily boost the immune response against SARS-CoV-2 variants and can be considered for specific groups of individuals. A heterologous vaccine strategy using mRNA vaccine in individuals primed with inactivated vaccine may boost immunity against variants. The timing of the fourth dose should be individualized but an interval of 4 months after the third-dose booster is appropriate. A universal fourth booster dose is not necessary.
Databáze: Directory of Open Access Journals