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H1N1 2009: Vaccines and antiviral resistance

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Yesterday brought news of two cases of Tamiflu resistant H1N1 2009 in the US and one in Singapore. It also brought the first authoritative news that our first delivery of vaccines for H1N1 2009 will be considerably less than first anticipated.

While on the surface Tamiflu resistance and a much smaller initial vaccination pool are separate issues, they are two variables in the pandemic equation that could change the very nature of our pandemic – and not in good ways.

First, something about the influenza vaccine itself. I am a very vocal advocate of vaccination, even the new “swine flu” vaccine. Much of the hysteria surrounding the launch of the vaccines is based on what the public has absorbed from the anti-vaccine crowd, also very “vocal”.

Because of the anti-vaccine crowd there will be a lot of people that will choose to not get vaccinated, what’s more alarming, they will choose to not have their children vaccinated. But, that’s further down the vaccine pipeline so I won’t wander off into that issue for the time being.

The very first group to have access to the supply of H1N1 2009 vaccine is going to be our health care professionals, those who deal with patients directly. That is absolutely as it should be. They are at the greatest risk of becoming infected by the very nature of the critically important job they do. These are jobs that require special education, training, and skill-sets. Jobs that have a finite labor pool, and in many places that labor pool is already woefully small and understaffed.

A snippet from CIDRAP’s Lisa Schnirring’s report, Officials lower expectations for size of first novel flu vaccine deliveries:

During a late July meeting of a federal immunization advisory panel, which targeted 159 million people to receive the first doses, authorities projected that 120 million doses would be available in October, with another 80 million per month in the following months.

However, during a National Biodefense Safety Board (NBSB) teleconference today, Dr. Robin Robinson, director of the Biological Advanced Research and Development Authority (BARDA) at the US Department of Health and Human Services (HHS), said the latest expectation is 45 million doses by mid October, with manufacturers delivering 20 million doses per week after that. [Emphasis added]

So, our first batch of available vaccine is looking like it will be about a third of what was planned. And, we still have to find out if the vaccine will take one injection, or two spaced 21 – 30 days apart, the two shot regime is the official assumption at this time.

Please pardon the abrupt shift in subject matter, but I will connect the two, I promise.

Helen Branswell [The Canadian Press] gave us an excellent and easily understood rundown on the dynamics of a very specific subset of patients who contract, or will potentially contract, H1N1 2009…

US swine flu patients on immunosuppressant drugs develop Tamiflu resistance [Excerpted snippet]

These new cases highlight the catch-22 of treating pandemic influenza in people who are severely immunosuppressed. These patients should be given flu drugs because their immune status leaves them highly vulnerable to severe illness. But giving them the drugs raises at least the theoretical risk that they will develop and spread antiviral resistant strains of the novel H1N1 flu.

It has been shown with seasonal influenza viruses that people with suppressed immune systems – either from birth, disease or because they are taking anti-rejection drugs following transplant surgery – can have prolonged viral replication when they get sick with flu.

Studies suggest such patients can shed viruses for weeks and even months.

If they are taking antiviral drugs, the longer they shed viruses, the more likely they are to develop resistance to the drugs. And if they develop drug resistance, they could – at least in theory – transmit those resistant viruses to others.

We, as a society, must not view this news as reason to marginalize a group of people, and if the past is any guide to the future, we will. However, I want to plainly state that while this segment of the population cannot do anything about their situation, we are not without means to minimize the potential threat.

When “your turn” comes up for a vaccine – get one. And, by the way, FluMist is not suffering production “issues”, while they are having some issues with running out of nasal spray devices, they have plenty of vaccine.

From the New York Times [30 July 2009]…

Nasal Vaccine Holds Promise Against Swine Flu [Excerpted]

MedImmune, which already makes the nasal spray vaccine FluMist for seasonal flu viruses, says it is on track to produce about five times as much swine flu vaccine as it had expected — so much, in fact, that it will run out of nasal spray devices and is looking to administer the vaccines with droppers instead.

[…]

We now are sitting on a surplus of potentially 150 million bulk doses,” Bernardus N. M. Machielse, executive vice president for operations, said in an interview.

BD, supplier of the sprayers, said Thursday that it was running its sprayer factory in Columbus, Neb., round the clock to increase annual capacity to 70 million sprayers — up from 20 million.

But even that will not be enough. So MedImmune wants to use droppers in addition to sprayers. Some early clinical trials of the vaccine were conducted with droppers, so the company hopes to win approval from the Food and Drug Administration to use them.

Unfortunately, the immunosuppressed or immunocompromised cannot take the FluMist vaccine because it is a live attenuated vaccine. FluMist uses a virus that replicates at a lower temperature than the human body, but it is still a live virus and those that receive might shed virus for a few days.

Because it uses a live, though attenuated, virus those who are immunosuppressed or immunocompromised cannot take the FluMist vaccine, nor can those who are around them, such as close contact family members or medical professionals who interact with them. In fact, FluMist is only approved for those between 2 and 49 years of age and healthy.

The “technicals” about what makes FluMist a wonderful [and superior] vaccine over the traditional shot in the arm are beyond the scope of this post [which is already too long] but it is – superior that is. It will also be available in greater numbers, that means it will be available to our school aged children, the viral drivers of influenza.

Get enough people vaccinated against the novel influenza and those immunosuppressed and immunocompromised individuals will have a significantly less chance of becoming infected in the first place. And, the few that happen to become infected stand a greater chance of only meeting up with vaccinated people – be they medical professionals or those they come into contact with in their day-to-day lives.

Which brings me to my last point: All you nurses and doctors out there: Roll up your sleeves and get that vaccine when it is offered to you. You not only risk becoming infected yourself, but once infected you risk infecting others – perhaps even those very immunosuppressed and immunocompromised individuals who may deliver to us a circulating strain of anti-viral resistant novel influenza.

They may not be able to do anything about their condition, but we are not powerless to prevent what their condition may mean to us as members of the wider society and population. Thus, the responsibility rests in our hands, or should I say “arms and noses” [injected and inhaled vaccines] to help prevent what those in this subset of population have no power to prevent [antiviral resistant novel influenza].

But, at the end of this post, I sit here knowing that it will be fear that we embrace. Fear of the vaccines and fear of immunosuppressed and compromised.

Fear.

Most times it’s senseless and irrational. Sometimes it’s real. When it’s real we are supposed to take action(s) to neutralize the threat.

We have our “weapons”.

Don’t let fear win the pandemic (and the graves of those who have fewer or no options) in the opening salvoes.

Get vaccinated if you can – as your ‘turn’ comes around.

In the name of full disclosure: I have no financial interests in any vaccine manufacturing company. I have no interest in any vaccine manufacturing company whatsoever beyond my fervent hope that they are wildly successful in delivering us effective and plentiful pandemic influenza vaccines.


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