15 April 2013
ByAppeared in BioNews 700
Synthetic biology is being used in the hunt for a vaccine for H7N9, the new strain of bird flu emerging in China, with hopes it could shave a vital two weeks off the vaccine's development process.
Using genetic sequence information posted on the website of the Global Initiative on Sharing Avian Influenza Data (GISAID), Synthetic Genomics and Novartis have been working on the development of a synthetic vaccine to protect against H7N9.
The scientists are attempting to create a vaccine that mimics the real virus, but importantly removing the pathogenic parts, allowing the body to develop specific immunity without contracting the flu. This method will take two weeks off the development process - critical when dealing with the rapid spread of an influenza pandemic.
Vaccine manufacturers normally rely on the World Health Organisation (WHO) to identify and distribute live viruses to create vaccines, while synthetic biology only requires the genetic sequence of the virus.
Learning from mistakes made during the SARS outbreak, scientists speedily identified that the zoonotic virus originated from a poultry market, sequenced its DNA and published the results online within six days.
From the genome sequence, many gene variants were identified, giving clues to the kind of threat the disease may pose. The mutation R292K, which causes a high-level resistance to the influenza drug Tamiflu and reduced sensitivity to Relenza, was shown to be present in a sample obtained from one patient in Shanghai.
The sequencing also showed the presence of the gene mutation Q226L, which indicates the ability to infect mammals. Q226L could enhance the ability of the virus to bind to receptors in the human upper air tract and was associated with the transmission of the H5N1 virus in 2009.
To date, 60 people have been infected and 13 killed by H7N9 since the new form of the virus was confirmed on 31 March 2013. There is still no evidence to suggest that it can spread from human to human, and experts believe that direct contact with diseased poultry accounts for the human cases. This has resulted in the slaughter of 20,000 birds in Shanghai and the closure of live chicken markets in both Shanghai and Beijing as the capital confirms its first case.
Michael O'Leary, the WHO's representative in China, said: 'There's no way to predict how it will spread but it's not surprising if we have new cases in different places like we do in Beijing'.