2009 swine flu pandemic vaccine

For information on other ways to decrease one's chances of contracting H1N1, see influenza prevention.

Influenza vaccines are typically developed to cope with seasonal flu to minimize infection rates, yet influenza still kills about 500,000 people a year around the world. In June 2009, a strain of influenza derived from swine influenza was declared a pandemic (see 2009 flu pandemic). This new strain, 2009 A/H1N1, was antigenically different from the existing seasonal strains, requiring the production of a vaccine distinct from the 2009-2010 seasonal flu vaccine.

Previous seasonal vaccine production

WHO recommended that vaccines for the Northern Hemisphere's 2009-2010 flu season contained an A(H1N1)-like virus. However, the version of H1N1 in the vaccine is a different, seasonal strain. Therefore, since the virus responsible for the outbreak is a new, swine-origin, non-seasonal strain of H1N1, the annual vaccination is not expected to result in human immunity. The CDC has characterized over 80 new H1N1 viruses that may be used in a vaccine.

Currently, most of the world's flu vaccines use an injection of "killed virus," a vaccine method made famous by Jonas Salk when he developed the first vaccine against the polio virus in 1955. As The Economist magazine summarized the problem, however, "if a global pandemic is declared and manufacturers are asked to produce a vaccine for [this new strain of] H1N1, they are unlikely to be able to respond quickly enough." Furthermore, vaccine producers can produce about a billion doses of any one vaccine each year, so that even if all the capacity was switched to fight a pandemic flu, as opposed to a seasonal flu, "there would still be a huge global shortfall." Keiji Fukuda of the WHO said, "There’s much greater vaccine capacity than there was a few years ago, but there is not enough vaccine capacity to instantly make vaccines for the entire world’s population for influenza." The seasonal flu vaccine is not believed to protect against the new strain, therefore any existing stock would not be useful.

Production questions and decisions

There was also concern that should a second, deadlier wave of this new H1N1 strain appear during the Northern autumn of 2009, producing pandemic vaccines now as a precaution could turn out to be a huge waste of resources with serious results, as the vaccine might not be effective against it, and there would also be a shortage of seasonal flu vaccine available. Seasonal flu vaccine was being made as of May, according to WebMD News. The news site adds that although vaccine makers would be ready to switch to making a swine flu vaccine, many questions remained unanswered, including the following: "Should we really make a swine flu vaccine? Should we base a vaccine on the current virus, since flu viruses change rapidly? Vaccine against the current virus might be far less effective against a changed virus - should we wait to see if the virus changes? If vaccine production doesn't start soon, swine flu vaccine won't be ready when it's needed."

The costs of producing a vaccine also became an issue, with some U.S. lawmakers questioning whether a new vaccine was worth the unknown benefits. Representatives Phil Gingrey and Paul Broun, for instance, were not convinced that the U.S. should spend up to $2 billion to produce one, with Gingrey stating "We can’t let all of our spending and our reaction be media-driven in responding to a panic so that we don’t get Katrina-ed. ... It’s important because what we are talking about as we discuss the appropriateness of spending $2 billion to produce a vaccine that may never be used — that is a very important decision that our country has to make."

Moreover, should a pandemic be declared and a pandemic vaccine produced, the WHO would attempt to make sure that a substantial amount is available for the benefit of developing countries. Vaccine makers and countries with standing orders, such as the U.S. and a number of European countries, will be asked, according to WHO officials, "to share with developing countries from the moment the first batches are ready if an H1N1 vaccine is made" for a pandemic strain. The global body stated that it wanted companies to donate at least 10 percent of their production or offer reduced prices for poor countries that could otherwise be left without vaccines if there is a sudden surge in demand.

Gennady Onishchenko, Russia's chief doctor, said on June 2 that swine flu is not aggressive enough to cause a worldwide pandemic, noting that the current mortality rate of confirmed cases was 1.6% in Mexico and only 0.1% in the United States. As a result, he stated at a press conference, "So far it is unclear if we need to use vaccines against the flu because the virus that is now circulating throughout Europe and North America does not have a pandemic nature." In his opinion, a vaccine could be produced, but said that preparing a vaccine now would be considered "practice," since the world would soon need a new vaccine against a new virus. "What's 16,000 sick people? During any flu season, some 10,000 a day become ill in Moscow alone," he said.

Production timelines

After a meeting with the WHO on May 14, 2009, pharmaceutical companies said they were ready to begin making a swine flu vaccine. According to news reports, the WHO's experts will present recommendations to WHO Director-General Margaret Chan, who is expected to issue advice to vaccine manufacturers and the World Health Assembly next week. WHO's Keiji Fukuda told reporters "These are enormously complicated questions, and they are not something that anyone can make in a single meeting." Most flu vaccine companies can not make both seasonal flu vaccine and pandemic flu vaccine at the same time. Production takes months and it is impossible to switch halfway through if health officials make a mistake. If the swine flu mutates, scientists aren't sure how effective a vaccine made now from the current strain will remain. Rather than wait on the WHO decision, however, some countries in Europe have decided to go ahead with early vaccine orders.

On May 20, 2009 AP reported: "Manufacturers won't be able to start making the [swine flu] vaccine until mid-July at the earliest, weeks later than previous predictions, according to an expert panel convened by WHO. It will then take months to produce the vaccine in large quantities. The swine flu virus is not growing very fast in laboratories, making it difficult for scientists to get the key ingredient they need for a vaccine, the 'seed stock' from the virus [...] In any case, mass producing a pandemic vaccine would be a gamble, as it would take away manufacturing capacity for the seasonal flu vaccine that kills up to 500,000 people each year. Some experts have wondered whether the world really needs a vaccine for an illness that so far appears mild."

Another option proposed by the CDC was an "earlier rollout of seasonal vaccine," according to the CDC's Dr. Daniel Jernigan. He said the CDC would work with vaccine manufacturers and experts to see if that would be possible and desirable. Flu vaccination usually starts in September in the United States and peaks in November. Some vaccine experts agree it would be better to launch a second round of vaccinations against the new H1N1 strain instead of trying to add it to the seasonal flu vaccine or replacing one of its three components with the new H1N1 virus.

The Australian company CSL said that they were developing a vaccine for the swine flu and predicted that a suitable vaccine would be ready by August. However, John Sterling, Editor in Chief of Genetic Engineering & Biotechnology News, said on June 2, "It can take five or six months to come up with an entirely novel influenza vaccine. There is a great deal of hope that biotech and pharma companies might be able to have something ready sooner."

Testing

According to ClinicalTrials.gov, Initial Phase I human testing began with Novartis' MF59 candidate in July 2009, and phase II trials of CSL's candidate CSL425 vaccine were planned to start in August 2009, but had not begun recruiting. Sanofi Pasteur's candidate inactivated H1N1 had several phase II trials planned as of 21 July 2009, but had not begun recruiting. News coverage conflicted with this information, as Australian trials of the CSL candidate were announced as having started on 21 July, and the Chinese government announce the start of trials of the Hualan Biological Engineering candidate.

Production before testing

Pressure for early delivery of vaccine has led some companies to take initial steps toward production of the vaccine before testing has been completed. This poses a small but serious economic risk for experienced manufacturers. In Great Britain, samples of a GlaxoSmithKline vaccine were expected to be available by the end of July, with adult clinical trial data available in September and pediatric data in October, but regulators were considering allowing the first distributions of vaccine to those most at risk before clinical data is available. The vaccine was designed using "core vaccines" previously tested in over 5000 people. Britain contracted to receive the first doses of vaccine by the end of August, which puts them at "the front of the queue" worldwide. According to Health Secretary Andy Burnham, "Nobody will receive vaccines before us." In Taiwan, the Adimmune Corporation has started production at its plant in central Taichung, based on preliminary animal tests. Human trials will not begin until September, but the company has committed to deliver five million doses of vaccine by the end of October. In the United States, Kathleen Sebelius predicted in July that the vaccine would not be available until mid-October, six or seven weeks after schoolchildren return to classrooms. However, members of the National Biodefense Science Board have recommended that production begin prior to testing with a goal of making vaccine available by September 15.

Production capacity

U.S.

As of June 4, 2009, Anne Schuchat, the Immunization Director of the CDC believed that little pandemic vaccine would be available by the fall, even if nothing goes wrong or delays production. The U.S. goal of pandemic plans is to make 600 million doses in six months, enough for two doses for each American, according to experts, with an estimated cost of $8 billion.

Although manufacturers had a seed virus, clinical trials of their first runs would last into the summer, and federal regulators must wait until trials are finished, according to the CDC's Schuchat. US domestic production capacity is still "completely inadequate," notes a 2008 Congressional Budget Office report, and it seemed unlikely that other nations would let vaccine factories on their soil export doses before their own needs are met.

Political issues

Since most of any H1N1 vaccine will be controlled by the federal government, the question of how it will be allocated should there be an insufficient supply for everyone is critical, and will likely depend on the patterns of any pandemic, and the age groups most at risk for serious complications, including death. The most likely case of a pandemic, people will be demanding access to vaccine and the major problem will be making it available to those who want it. While some have argued that the federal or state governments could force people to be vaccinated in a pandemic, there are no constitutional authorities that permits the government to vaccinate competent adults. The only populations likely to face compelled vaccination are deployed military personnel (who can be given routine vaccinations as part of their service obligations), health care personnel (whose employer can require vaccinations to protect patients), and grade school and day care students, who could be required to be vaccinated as a condition of attending school --at least if public health authorities make this recommendation based on the increased risk to this population.