Influenza Virus and Vaccines

Influenza

• Highly infectious acute disease
• First influenza A strain was isolated in 1933
• In 1946, different strains appeared
• Variant A2 strain was responsible for the pandemic of 1957
• Influenza virus for vaccine manufacture is prepared in embryonated hen's eggs
• Type A and type B components are standardized by hemagglutination titration before dilution and blending into a vaccine
• Living attenuated virus is sprayed into the nose in USSR
• Isolated hemagglutinin of the virus is immunogenic and does not give rise to febrile and toxic reactions
• ϒ-globulin may help to neutralize the viraemia when administered in the early stages before the virus has infected nerve cells

Poliomyelitis

• Preventable disease
• Killed vaccine is produced by monkey kidney cell cultures
• Immunization: 2 doses given by IM at an interval of 4-6 weeks, followed by a similar dose given 9-12 months later, and a fourth dose 5-6 years later
• Killed vaccine can be incorporated with Diphtheria, tetanus, and pertussis prophylactics (quadruple vaccine)
• Live vaccine is made by infecting monkey kidney or human embryo lung fibroblast cell cultures with attenuated virus strains
• Vaccine is given orally as monovalent virus in the order of Type 1, followed by Type 3, and finally Type 2, with an interval of 6 weeks between each dose

Passive Immunization

• ϒ-globulin Prepared from recently vaccinated donors protects unvaccinated household contacts of smallpox or persons last vaccinated many years previously
• Control vaccinia and vaccinial infections of the eye can be controlled by ϒ-globulin (500 mg - 2.0 g) depending on patient age

Chickenpox (Varicella)

• Acute infectious disease caused by a virus close to herpes zoster
• Prevention using ϒ-globulin

Herpes Simplex (Febrillis)

• Infectious virus disease occurring in tropical and subtropical zones
• Vaccine injected subcutaneously

Rabies

• Antiserum is produced in horses
• Plasma from hyperimmune horses is used for antioxidant sera

Hepatitis

• Acute sporadically or in epidemics, caused by a virus spread by ingesting food or water contaminated with feces
• Epidemics of infectious hepatitis (viral hepatitis A) have been successfully controlled by an injection of ϒ globulin prepared from normal adult serum
• Prophylactic ϒ globulin is recommended to all contacts of infectious hepatitis, especially pregnant and post-menopausal women, as early as possible after exposure, and confers protection even if given as late as 6 days before the onset of symptoms

Measles (Rubeola)

• Highly infectious acute disease caused by measles virus
• The disease can be attenuated or completely prevented by ϒ – globulin prepared from pooled adult serum
• Killed vaccine prepared by formalin treatment of virus grown in either monkey kidney or dog kidney cells