Science and Technology · Biotechnology and Health

With reference to recent developments in vaccine technologies and antimicrobial resistance (AMR), consider the following statements: I. Self-amplifying mRNA vaccines are designed to replicate antigen-encoding genetic material within host cells, thereby potentially requiring lower doses compared to conventional mRNA vaccines. II. Recombinant chimeric vaccines necessarily use attenuated whole pathogens and cannot employ genetic material derived from multiple strains or species. III. Antimicrobial resistance may emerge naturally in microorganisms, but irrational antibiotic use and environmental contamination can accelerate the process. IV. Gram-negative bacteria are generally considered less capable of developing multidrug resistance because of the presence of an additional outer membrane. How many of the statements given above are correct?