Meningococcal polysaccharide A + C + Typhoid Vi polysaccharide vaccine

This is a combination vaccine containing purified capsular polysaccharides from *Neisseria meningitidis* serogroups A and C (meningococcal A and C) and the Vi capsular polysaccharide from *Salmonella enterica* serovar Typhi (typhoid Vi). The vaccine is designed to provide active immunization against both invasive meningococcal disease caused by *Neisseria meningitidis* serogroups A and C, as well as typhoid fever caused by *Salmonella* Typhi. The mechanism of action involves induction of specific antibodies against the respective bacterial capsular antigens, conferring protection by preventing bacterial invasion and subsequent infection. These vaccines are typically administered intramuscularly, often in regions where both diseases are endemic or for travelers to such areas[2][5]. Sodium chloride serves as an excipient to maintain isotonicity.