Patient description: The patient is a 23-year-old man who came to the hospital with high blood pressure (175/95 mmHg) and signs of septicemia. He developed respiratory failure requiring mechanical ventilation and renal failure requiring hemodialysis. His blood smear showed microangiopathic hemolytic anemia and thrombocytopenia. His blood tests revealed elevated lactate dehydrogenase and reduced human complement C3 levels with a normal coagulation profile. He was diagnosed with atypical hemolytic uremic syndrome. He was treated with plasma exchange and corticosteroids. He has been previously vaccinated with meningococcal group ACWY conjugate vaccine and meningococcal group B vaccine. The genetic survey revealed ADAMTS13 >10%.

Clinical trial eligibility criteria: eligible ages (years): 0.167-55.0,  Meningococcal Infections Healthy children, adolescents and adults (age range: 2 months to 55 years old) based on medical history, physical examination or judgement of the investigator Subjects aged ≥18 years old voluntarily agree to participate in this clinical study and sign the informed consent form; or for subjects aged <18 years old, the legal guardian voluntarily agrees that his/her child to participate in this clinical study, and sign the informed consent form. For juveniles aged ≥8 years old, both the subject and his/her legal guardians should voluntarily agree to participate in this clinical study and sign the informed consent form The subject and his/her legal guardians as well as the family members are able to follow the request of clinical study protocol Subjects aged 2 or 3 months should have no vaccination history of any meningococcal vaccine; subjects aged 7~23 months should have not received any other meningococcal vaccine except the meningococcal group A polysaccharide vaccine included in National Immunization Program, and the time since last vaccination of meningococcal group A polysaccharide vaccine should be >6 months; for subjects ≥2 years, the time since last vaccination of meningococcal vaccine should be >2 years For subjects aged ≥2 years, there should be no clinically significant abnormal hematology, liver and renal function results judged by the investigator before immunization Subjects should not receive any attenuated live vaccine 14 days, or inactivated vaccine 7 days before or after vaccination Axillary temperature ≤37.0℃  for First Dose Subjects aged 2 or 3 months at enrollment with birth weight <2.5 kg Subjects aged 2 or 3 months at enrollment had received blood products and immunoglobin after birth; subjects of other age groups had received blood products or immunoglobin in <3 months before vaccination Subjects aged <12 months at enrollment are diagnosed as with pathological jaundice or have a history of pathological jaundice Subjects aged <2 months at enrollment had abnormal labor (dystocia, assisted instrumental delivery) or with the history of asphyxia or nervous damage Subjects aged ≥18 years who are planning pregnancy, or are pregnant, or are breastfeeding Subjects aged ≥18 years with uncontrollable hypertension (during screening: systolic BP >140 mmHg or diastolic BP >90 mmHg) Subjects are known to be allergic to certain components contained in the investigational vaccine (mainly capsular polysaccharide of meningococcal group A, group C, group Y, or group W135, diphtheria toxoid or diphtheria antigen) Subjects with the history of serious allergy to any vaccine or drug. (including but not limited to: allergic shock, allergic laryngeal edema, allergic purpura, thrombocytopenic purpura, local allergic necrosis reaction [Arthus reaction]) Subjects with the history of meningitis