Influenza

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In many cases, only a handful of suppliers produce vaccines for a given disease.  In fact, for several vaccine types the U.S. has fewer suppliers than countries with a smaller market and a higher level of government purchase.

One reason for this finding could be strict government regulation.  All vaccines must be approved by the FDA.  Further, the CDC provides guidelines to physicians regarding who should get which vaccines.  The CDC also is a large purchaser of vaccines.  Thus, at first glance, it seems that government regulation may be causing industry consolidation in the vaccine market.

A paper by Danzon and Pereira, however, finds this not to be the case.  They find that the likelihood a supplier exits from a particular vaccine market is not effected by whether the CDC is a purchaser of the vaccine, the amount of vaccine the CDC purchases, or the CDC price at the time the firm exits.

The authors propose that the large economies of scale in vaccine production are the cause of the lack of competition in the vaccine market.

The vaccine industry is characterized by large fixed costs of initial vaccine development as well as substantial ‘semifixed’ costs of producing an individual batch (a process that may take 6 to 18 months) but low marginal costs of producing an additional dose, up to the batch limit, and low storability. If there are multiple competing suppliers with large sunk costs and low marginal costs, competition may drive the price low enough that it is relatively unattractive for multiple firms to remain in the market and for new firms to enter.

Further, the demand for vaccines is price sensitive.  Insurers (public and private) typically pay physicians and hospitals a fixed payment per vaccine administered.  Increases in vaccine costs come directly from the provider’s bottom line.

Some observers may point to the 2004-2005 influenza vaccine shortage and claim that government regulation had to cause this shortage.  The authors note that although several suppliers did exit the market before the shortage years, “…this cannot be blamed on government purchase and price controls, as less than 20 percent of the flu vaccine is publicly purchased.”

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Although the H1N1 influenza virus has garnered most of the media attention, protecting children against standard strains of influenza has generally been shown to be cost effective.  However, the cost effectiveness depends on the timing.  The flu season generally lasts from September to June, but flu generally has the highest incidence in November and December. A paper by Yee et al. (2010) claims that getting all kids immunized could save society between $6.4 million and $9.2 million.  Even third party payers (i.e., insurers) save between $4.1 and $6.1 million due to decrease hospitalization and illness.

The authors find that vaccinating children is cost-effective until December for trivalent inactivated viral vaccine (TIV).  Live attenuated influenza vaccine (LAIV) , however, is only cost effective through November.  But should you believe these recommendations?

Read the rest of this entry »

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It is sometimes called the Great Swine Flu epidemic and sometimes the Great Spanish Flu epidemic, but in either case it was ferocious.  World War I killed twenty-one million people in four years; swine flu did the same in its first four months.  Almost 80 percent of American causalities in the First World War came not from enemy fire, but from flu.  In some units the mortality rate was as high as 80 percent.

This passage is from an interesting book I am currently reading called A Short History of Nearly Everything by Bill Bryson.  An (unfortunately) prescient passage in the book describes a certain flu virus we all became familiar with last summer:

From time to time certain strains of virus return.  A disagreeable Russian virus known as H1N1 caused severe outbreaks over wide areas in 1933, then again in the 1950s, and yet again in the 1970s.  Where it went in the meantime each time is uncertain.  One suggestion is that viruses hide out unnoticed in populations of wild animals before trying their hand at a new generation of humans.  No one can rule out the possibility that the Great Swine Flu epidemic might once again rear its head.

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Two weeks ago, the U.S. government released its H1N1 vaccine to the public.  Many people have had a number of questions about whether or not they should get the vaccine.  The CDC website has a list of Key Facts and a Q&A section that is helpful.  

There are five major groups who should have priority of getting the vaccine:

  • pregnant women,
  • people who live with or provide care for infants younger than 6 months (e.g., parents, siblings, and day care providers),
  • health care and emergency medical services personnel,
  • people 6 months through 24 years of age, and,
  • people 25 years through 64 years of age who have certain medical conditions that put them at higher risk for influenza-related complications.

There are a number of people who should NOT get the vaccine.

  • People who have a severe allergy to chicken eggs.
  • People who have had a severe reaction to an influenza vaccination.
  • People who developed Guillain-Barré syndrome (GBS) within 6 weeks of getting an influenza vaccine previously.
  • Children younger than 6 months of age (influenza vaccine is not approved for this age group), and
  • People who have a moderate-to-severe illness with a fever (they should wait until they recover to get vaccinated.)

The H1N1 vaccine is prepared using the same method as used for the seasonal flu.  However, because the H1N1 vaccine was developed too late, it could not be added to the seasonal flu vaccine.  Thus there are two flu shots available now, one for the seasonal flu and one for H1N1. 

If you think you have the H1N1 illness, you can use this self assessment tool to verify whether or not you should see a doctor.

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The Washington Post reports that most Americans are not very concerned about swine flu.  Should they be worried?  Maps from the New England Journal of Medicine and RhizaLabs detail that swine flu is still a problem.

The CDC reports that “from April 15, 2009 to July 24, 2009, states reported a total of 43,771 confirmed and probable cases of novel influenza A (H1N1) infection. Of these cases reported, 5,011 people were hospitalized and 302 people died.”  However, the CDC does not seem too concerned either.  The CDC has decided to discontinue confirmed and probable case counts on July 24, 2009 (aggregate national reports of hospitalizations and deaths will continue ).

So it is logical for Americans to not be concerned about H1N1?  I believe that public health officials still need to take H1N1 very seriously.  It is very likely that a second H1N1 outbreak will occur this fall and winter during flu season.  During the traditional flu season, H1N1 monitoring must increase.

For the average American, however, I believe there is little reason to worry.  This is not because they will not get H1N1, but instead because there are only a few steps they can take to prevent it.  The CDC recommends: avoiding sick people, washing your hands frequently and covering your face with a tissue when you sneeze.  The first two steps will help prevent you from getting H1N1, but both are logical and most people should already be doing these.  The third step will not help prevent you from getting H1N1, but will prevent the spread of the disease to others if you have it.

The Healthcare Economist’s advice to you is wash your hands, avoid sick people and–until flu season begins–worry about something else other than H1N1.

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Carl Coleman say no.  

Working during a pandemic is a supererogatory behavior — i.e., acts that are commendable if done voluntarily, but that go beyond what is expected.  Coleman argues that “…while health care professionals can legitimately be sanctioned for violating voluntarily-assumed employment or contractual agreements, they should not be compelled to assume life-threatening risks based solely on their status as licensed professionals. In place of singling out health care professionals for punitive measures, the Article argues that policy-makers should institute mechanisms to promote volunteerism.”

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Google searches as a public health resource:

Google.org has released Flu Trends, an online reporting tool for flu-related search activity. It’s long been theorized that Google’s search data would be useful to predict epidemics. This is the first time they’ve released a tool like this to the public. As they say on the main page:

We have found a close relationship between how many people search for flu-related topics and how many people actually have flu symptoms. Of course, not every person who searches for “flu” is actually sick, but a pattern emerges when all the flu-related search queries from each state and region are added together. We compared our query counts with data from a surveillance system managed by the U.S. Centers for Disease Control and Prevention (CDC) and discovered that some search queries tend to be popular exactly when flu season is happening. By counting how often we see these search queries, we can estimate how much flu is circulating in various regions of the United States.

This tool comes to us via Google.org’s Predict & Prevent initiative. You can download the data for your own analysis.

[Update, 14 May 2009: Google is refining their Flu Trends data by asking people questions about their flu searches.]

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Vaccines work well because of an adjuvant. The adjuvant boosts immunity but physicians did not know how it worked until now. The Economist reports (“A shot in the dark not more“) that Stephanie Eisenbarth, Richard Flavell an co-authors have discovered that the adjuvant “works by stimulating bits of the immune system called NOD-like receptors.”

Why is this discovery important?

The value of that is shown by another piece of news. This week GlaxoSmithKline, a big British drug company, won the European Union’s approval for a ‘pre-pandemic’ vaccine that promises protection against multiple strains of bird flu. This vaccine depends, according to Emmanuel Hanon, who helped develop it, on an oil-in-water-emulsion adjuvant so good that only a twentieth of the normal amount of antigen is needed. So how does this amazing adjuvant work? Dr Hanon admits that his team does not actually know.

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According to Reuters (“All U.S. kids…“), the CDC’s Advisory Committee on Immunization Practices (ACIP) is recommending that all kids should receive an influenza vaccination. Previously, the CDC recommended that all children 0-6 receive a flu shot. Now, all children 18 and under should get the shot.

In addition to the direct health benefits the children will receive from a decreased likelihood of getting the flu, the probability that they will spread it to adults, teachers, other children, and senior citizens will decrease.

However, there will be costs to the flu vaccine expansion. According to the U.S. Census, there were 61.3 million children aged 5-19 in the U.S. Getting all these children vaccinated will be very costly and since the vaccines will be given in the fall, the logistics of providing 61 million additional flu shots will be difficult to manage.

Further, one of my working papers (“Adam Smith meets Jonas Salk: Estimating the Social Cost of Third-Party Influenza Vaccination Restrictions“) finds that when kids 0-18 year old must receive a flu vaccine efficiency losses could increase to as much as $560 million if insurance companies continue to prohibiting reimbursement to pediatricians for vaccinating adults.

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