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Influenza virus prophylactic

What is influenza?

Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae (the influenza viruses), that affects birds and mammals. The name influenza is Italian and means "influence" (Latin: influentia). The most common symptoms of the disease are chills, fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort. Sore throat, fever and coughs are the most frequent symptoms. In more serious cases, influenza causes pneumonia, which can be fatal, particularly for the young and the elderly. Although it is often confused with other influenza-like illnesses, especially the common cold, influenza is a much more severe disease than the common cold and is caused by a different type of virus.

Typically, influenza is transmitted through the air by coughs or sneezes, creating aerosols containing the virus. Influenza can also be transmitted by direct contact with nasal secretions, or through contact with contaminated surfaces. Airborne aerosols have been thought to cause most infections.

How serious is influenza?

Influenza spreads around the world in seasonal epidemics, resulting in the deaths of hundreds of thousands worldwide annually, and millions in pandemic years. On average 41,400 people died each year in the United States between 1979 and 2001 from influenza. Three influenza pandemics occurred in the 20th century and killed tens of millions of people, with each of these pandemics being caused by the appearance of a new strain of the virus in humans. Often, these new strains appear when an existing flu virus spreads to humans from other animal species, or when an existing human strain picks up new genes from a virus that usually infects birds or pigs. An avian strain named H5N1 raised the concern of a new influenza pandemic, after it emerged in Asia in the 1990s, but it has not evolved to a form that spreads easily between people. In April 2009 a novel flu strain evolved that combined genes from human, pig, and bird flu, initially dubbed "swine flu" and also known as influenza A/H1N1, emerged in Mexico, the United States, and several other nations. The World Health Organization officially declared the outbreak to be a "pandemic" on June 11, 2009.  The WHO's declaration of a pandemic level 6 was an indication of spread, not severity.

What is the current treatment of influenza?

Vaccinations against influenza are usually given to people in developed countries. The most common human vaccine is the trivalent influenza vaccine (TIV) that contains purified and inactivated material from three viral strains. Typically, this vaccine includes material from two influenza A virus subtypes and one influenza B virus strain. The TIV carries no risk of transmitting the disease, and it has very low reactivity. A vaccine formulated for one year may be ineffective in the following year, since the influenza virus evolves rapidly, and new strains quickly replace the older ones. Antiviral drugs can be used to treat influenza, with neuraminidase inhibitors being particularly effective.

How is the new treatment different?

The new treatment targets the viral receptors and blocks these so influenza virus cannot gain entry to the respiratory epithelium.

  • We have engineered a panel of recombinant proteins that have up to nanomolar affinity for sialic acid and bind to cell surfaces. They are designed to mask the receptors of the influenza (and parainfluenza) virus in the respiratory tract. The recombinant therapeutic proteins are easily produced and purified to give 15-80mg/L of bacterial cell culture. The proteins are also susceptible to further modification.
  • In-vitro experiments show that the proteins are effective at blocking the entry of influenza virus into cells in a dose-dependent manner, as shown in virus plaque assays (above).
  • In-vivo work demonstrates that the proteins are tolerated well by healthy mice, and that intranasal delivery protects the respiratory epithelial mucosa from influenza virus attack.
  • The proteins are candidate prophylactic antivirals against influenza and parainfluenza virus infection.

For further details you can download the Information Sheet from this page or contact us



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