Neisseria meningitidis
The most commonly used conjugate vaccine is the Hib conjugate vaccine. Other pathogens that are combined in a conjugate vaccine to increase an immune response are "Streptococcus pneumoniae" and "Neisseria meningitidis"", both of which are conjugated to protein carriers like those used in the Hib conjugate vaccine. Both "Streptococcus pneumoniae" and "Neisseria meningitidis" are similar to Hib in that infection can lead to meningitis. As of 2018, the latest conjugate vaccine is typhoid conjugate vaccine which may be more effective and prevents typhoid fever in many children under the age of five years.