Experts from around the world are in daily talks about the threat posed by a
deadly new strain of bird flu in China, including discussions on if and when to
start making a vaccine.
Any decision to mass-produce vaccines against H7N9 flu will not be taken
lightly, since it will mean sacrificing production of seasonal shots. And
scientists warn it will take months to get any finished bird flu vaccine to the
But the groundwork is being laid. The virus has been shared with World Health
Organization (WHO) collaborating centers in Atlanta, Beijing, London, Melbourne
and Tokyo, and these groups are analysing samples to identify the best candidate
to be used for the manufacture of vaccine - if it becomes necessary.
It is still a big "if", even assuming the continued spread of the new
disease, which has killed five of the 14 people that it has infected in
"It is an incredibly difficult decision because once you make it you have to
change from making seasonal flu vaccines and go to making a vaccine for this
virus," said Jeremy Farrar, a leading expert on infectious diseases and director
of Oxford University's research unit in Vietnam.
That could mean shortages of vaccine against the normal seasonal flu which,
while not serious for most people, still costs thousands of lives.
Sanofi Pasteur, the world's largest flu vaccine manufacturer, said it was in
continuous contact with the WHO through the International Federation of
Pharmaceutical Manufacturers and Associations (IFPMA), but it was too soon to
know the significance of the Chinese cases.
Other leading flu vaccine makers include GlaxoSmithKline and Novartis.
Preliminary test results suggest the new flu strain responds to treatment
with Roche's drug Tamiflu and GSK's Relenza, according to the WHO.
Money down the drain?
There is no evidence yet of person-to-person transmission of H7N9 flu, and
scientists do not yet know how what the strain's potential is to develop into a
Wendy Barclay, a flu virologist at Imperial College London, said one major
argument against moving too soon would be financial.
"There is a possibility now that flu researchers will all rush to work on
H7N9 and grants will be awarded for intensive research to develop vaccines ...
and that could be pouring money down a drain because it could be that the
barriers for this virus are high enough that we don't need to worry about
She said scientists should first be focused on getting "the practical biology
and the sequence analysis" before they decide to move on.
Since the H1N1 swine flu pandemic of 2009, in which drug makers took six
months to develop and distribute effective vaccines, manufacturers have been
stepping up efforts to produce shots faster to deal with the rapid spread of
It remains a lengthy process, however.
"There is presently no technology that can quickly and cost-effectively
mass-manufacture vaccine," said Anton Middelberg, a flu vaccine researcher at
the University of Queensland. "Although the WHO is sending materials for vaccine
development to China, it is unlikely that vaccine will be produced quickly
enough to impact this outbreak."
Still, the flu vaccine community is not starting completely from scratch.
A degree of preparedness already exists because the last WHO vaccine strain
selection meeting in February had already decided to consider the broad H7 virus
category as a pandemic candidate.
The European Center for Disease Prevention and Control said vaccine candidate
strains had also been developed as a response to previous H7 human cases in
Europe and North America.
"These candidate strains may not efficiently cross protect against the novel
A(H7N9) strain, but the fact that they are moving towards development does
indicate a degree of preparedness globally," the ECDC said.