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What is Xavier and yogender stayed in the same hostel of the same university. Xavier develops an infection due to group B meningococcus. After few days yogender develops an infection due to Group C meningococcus. All of the following are true statements except and explain in detail?
Monovalent and polyvalent vaccines containing the capsular polysaccharides of groups A, C, W-135 and Y are available. The vaccine induces good immunity after a single dose in older children and adults but is of little value in children below 2 years of age as the polysaccharide antigen is T-cell independent. Immunity is group specific. There is no group B vaccine available at present. Conjugate vaccine is now available, where the polysaccharide antigen conjugated to the diphtheria toxoid which makes the vaccine immunogenic for children below the age of 2 years. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 233