Description

Inflexal^® V is a virosomal adjuvanted Influenza vaccine (subunit), based upon the virosome technology developed and patented by the Crucell company, Berna Biotech. It is the only adjuvanted Flu vaccine licensed for all age groups (up from 6 months). The vaccine’s antigen composition follows yearly WHO recommendations.

 

Inflexal^® V was originally introduced in 1997, is registered in 43 countries and has extensive market experience, with more than 40 million doses confirming its safety profile. The tolerability of Inflexal^® V is excellent due to its biocompatibility and purity. Neither thiomersal nor formaldehyde is contained within the vaccine, and the manufacturing process of Inflexal^® V allows residual quantities of antibiotics, detergent and hen’s egg protein to be minimal compared with other influenza vaccines.

About influenza

Influenza, commonly called the flu, is a highly contagious infection of the respiratory tract that spreads from person-to-person through infectious respiratory secretion droplets caused by coughing or sneezing. Influenza outbreaks occur almost every year and their severity varies considerably. One unique aspect of influenza, compared with other viruses, is its ability to perpetually change over time, usually by mutation. This characteristic enables the virus to evade the immune system of its host, making people susceptible to the flu throughout their entire life. When infected with the virus, a person develops antibodies that work against that virus. Once the virus changes, however, the previous antibodies are unable to recognize it, necessitating an entirely new antibody response to fight off the virus. These modifications make it necessary for individuals to receive a different influenza vaccination each year, compared with one vaccination that would grant lifetime immunity.

Morbidity and mortality

Each year approximately 10-20% of the world's population contracts influenza and on average 3 to 5 million people suffer severe illness. An estimated 250,000 to 500,000 people die annually from influenza-associated complications. Influenza becomes a life-threatening disease among a number of patient populations such as the very young and the elderly, and all individuals with an underlying disease. Influenza outbreaks and epidemics (November to March represents the peak season in the Northern Hemisphere) cause an increase in hospital admissions and deaths. Yearly routine immunization is therefore recommended for these risk groups by public health authorities. Occasionally a major genetic variation in the influenza virus may result in a deadly new virus strain to which the human population does not have immunity, and a global pandemic outbreak occurs. The Spanish influenza pandemic, the most severe outbreak of influenza to date, occurred from 1918 to 1920 and caused deaths worldwide ranging in estimation from 20 to 60 million.

 

While the flu affects individuals of all ages, approximately 90% of flu-related deaths occur among individuals above the age of 65. People with chronic medical conditions and young children also have a higher risk of suffering influenza complications.

Geographical distribution

The influenza virus occurs worldwide. In temperate regions, influenza occurs during the winter months, affecting the northern hemisphere from November to March and the southern hemisphere from April to September. In tropical regions influenza may occur at any time of the year.

Transmission

Influenza transmission occurs mostly by breathing in respiratory droplets that enter the air when an infected person coughs or sneezes. Transmission also occurs through direct contact with respiratory droplets or secretions, followed by touching the nose or mouth.

Symptoms

Influenza leads to a variety of symptoms, ranging from mild to severe. One to four days after exposure to the virus, the illness starts very suddenly over a period of hours. Common symptoms include fever, headache, muscle ache, extreme fatigue, sore throat, cough and nasal congestion. While symptoms usually abate within one to two weeks, the virus can often lead to further, life-threatening complications, such as pneumonia. One of the most common misconceptions about influenza is that the symptoms of stomach flu (vomiting, diarrhea, and nausea) are related to influenza. Stomach flu is usually caused by bacteria or parasites and is rarely related to the influenza virus.

Treatment and prevention

The most effective way to counter influenza is to be vaccinated against influenza. Vaccination has shown to be successful in protecting against dangerous influenza-related complications that could lead to hospitalization and death. The overall effectiveness of the yearly vaccine is dependent on its ability to match the strains that cause the illness. According to the National Foundation for Infectious Diseases, the influenza vaccine can prevent disease symptoms in 70-90% of healthy young adults. Influenza vaccine manufacturers include particular strains of the virus for inclusion in the vaccine, based on annual recommendations received from the World Health Organization (WHO).

 

Current influenza virus vaccines are administered via injection and are based on inactivated (killed) whole viruses that are grown in chicken eggs, harvested, chemically inactivated, purified and processed into vaccines. Throughout the multi-stage manufacturing process, the vaccine is tested for consistency, safety, and its ability to stimulate antibody production.

 

Demand for influenza vaccines is expected to more than double by 2010, driven by risks of a new influenza pandemic, the world's ageing population, and broader government vaccination recommendations. The U.S. Centers for Disease Control (CDC) recently lowered the recommended age for vaccination from 65 to 50 and has added infants between the ages of six and 23 months. Across Asia, governments have already broadened their vaccination recommendations to minimize confusion between influenza and SARS infections, with Singapore now recommending annual influenza vaccination for the entire population. In Europe, recommendations could also evolve in future years. For example, since the beginning of 2003, influenza vaccination has been encouraged in Belgium for those 50 years of age and older.

 

For more information visit Useful Links