Property has no initializer and is not definitely assigned in the constructor (when declaring new variables in typescript)

Question

export class Patient {

  icNumber: string;
  fullname: string;
  password: string;
  birthday: Date;
  gender: string;
  address: string;
  email: string;
  phoneNumber: string;
  emergencyContactNumber: string;
  emergencyRelationship: string;
  height: number;
  weight: number;
}

All lines have the same error. How can I resolve this issue?