# 8416
Tomorrow, March 31st, will be the one-year anniversary of the world’s notification from the Chinese MOH that a new avian flu virus – H7N9 – was spreading and infecting people in China (see China: Two Deaths From H7N9 Avian Flu). In these past 12 months more than 400 human infections have been recorded – a milestone that took the H5N1 virus roughly 6 years to reach (2003-2008).
While the closure of live-markets in many of the larger towns and cities in China seems to have reduced the rate of human infection over the past couple of months, we continue to see scattered cases reported from several provinces in Eastern China.
As avian flu spreads best in cold temperatures, public health officials in China are anxiously awaiting the arrival of summer, which they hope will provide a respite in transmission of the virus. They are very aware, however, that the virus could easily return next fall.
This morning, we’ve some comments from Hong Kong’s Secretary of Food & Health Dr. Ko Wing-man, on this expected reduction in the H7N9 threat, and on prospects on when a vaccine for humans would be available.
You may recall that earlier this month, in Parsing China’s H7N9 Vaccine Headlines, we looked at some dubious Chinese media claims, suggesting that a vaccine was only a couple of months away. Given that only phase I (animal) trials had been conducted on the vaccine, some of the promises (see Xinhua News H7N9 vaccine may hit market in May) seemed more than a little ambitious.
Dr. Ko Wing-man provides a far more plausible timetable, in his remarks which are carried in the following item published overnight by the Hong Kong Government.
H7N9 cases to decline: Health chief
March 30, 2014
Secretary for Food & Health Dr Ko Wing-man says the threat from H7N9 will decrease as temperatures rise, but the Government will stay vigilant.
Briefing reporters today, Dr Ko said H7N9 cases have decreased since Mainland authorities adopted preventive measures, and added he hoped the contingency plan for local chicken sales would not have to be activated after Mainland live chicken imports resume in June.
Noting concerns from Ta Kwu Ling residents on the plan, he said the Government will continue to communicate with them and will minimise environmental impacts.
Dr Ko also said the Government will conduct a study in May to formulate a contingency plan for the coming winter, including the use of a new vaccine against H7N9.
"According to our experts, the experts in the Mainland have already obtained the licence for experiment. The earliest possible available time frame would be around the end of the year or early next year. However, as to the application of this new vaccine, it remains to be discussed among the scientists and the authorities."
While work is being done on an H7N9 vaccine in China, Taiwan, Japan, and the United States - and there are hopes that a suitable one can be created – we’ve seen evidence in the past that effective H7 (and H5) flu vaccines are harder to make than their seasonal cousins.
Last May we saw an analysis of some of the problems inherent in creating and deploying an H7N9 vaccine published in JAMA, penned by CIDRAP’s Michael T. Osterholm, PhD, MPH; Katie S. Ballering, PhD; and Nicholas S. Kelley, PhD.
Major Challenges in Providing an Effective and Timely Pandemic Vaccine for Influenza A(H7N9)
Michael T. Osterholm, PhD, MPH; Katie S. Ballering, PhD; Nicholas S. Kelley, PhD
JAMA. 2013;():1-2. doi:10.1001/jama.2013.6589.
Published online May 9, 2013
Issues such as the correct amount of antigen per shot, the timing or need for a booster shot, the incidence and severity of side effects, and even the need for an adjuvant are usually sorted out during several rounds of clinical (human) testing, something that can take months or even years.
Last September (see NIH Begins Phase II Clinical Trials On H7N9 Vaccine Candidates) the NIH released a detailed summary of their plans to test a variety of H7N9 vaccine formulations across two clinical trials - involving as many as 1700 volunteers - who will receive various strength H7N9 vaccines (adjuvanted and non-adjuvanted).
When complete, we should have a much better idea of what will be involved in creating a pandemic H7N9 vaccine. Full results, however, are not expected until December of 2014.
And assuming no major obstacles are encountered during these clinical trials, there’s several months of vaccine production, fill and finish, shipping, and local distribution to take into account. But the reality is - In a world of 7 billion people- our ability to manufacture and (just as importantly) distribute a pandemic vaccine in a short amount of time remains severely limited.
Realistically, all of this means we are still a long way from having adequate amounts of commercial H7N9 vaccine available to the general public.
Should H7N9 (or any other novel virus) spark a major epidemic or worse – a pandemic – then our first line of defense will be NPIs or Non-Pharmaceutical Interventions. The CDC’s Nonpharmaceutical Interventions (NPIs) webpage defines NPIs as:
Nonpharmaceutical interventions (NPIs) are actions, apart from getting vaccinated and taking medicine, that people and communities can take to help slow the spread of illnesses like influenza (flu). NPIs are also known as community mitigation strategies.
NPIs are geared to the virulence and spread of the virus, and may range from simple advice to `wash your hands and cover your coughs’ to mandatory school and business closings.
Vaccines would eventually play an important role in the containment of any pandemic, but likely not until the second or third wave of infection. And even then, they would initially only be available to a fraction of the world’s population.
Despite having been depicted in movies and TV shows as the panacea for any pandemic, the rapid global rollout of an experimental (and untested) vaccine is something that only really happens in in the minds of Hollywood screenwriters.
