Updates: H1N1 vaccine supply and NY health care worker mandates

There's more coverage of the H1N1 vaccination program than we or anyone else can digest. However, this story from yesterday's Washington Post, "Why such a shortage of swine flu vaccine?" does a very good job examining the most common topic of late, the recent shortfall in H1N1 vaccine supply compared to government and manufacturer predictions. (Whether this technically qualifies as a 'shortage' is up for debate.)

According to this Associated Press report late yesterday, the vaccine supply situation seems to be improving. Hopefully, interest in the vaccine will remain high until adequate vaccine doses become available. Otherwise, it's quite possible that later this winter, health officials will find themselves with the opposite problem -- millions more doses of H1N1 vaccine than citizens making an effort to receive it.

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In related news, we wrote several posts earlier this month on mandatory vaccination policies for health care workers, particularly the statewide program in New York. Citing inadequate supplies of both H1N1 and seasonal flu vaccines, Gov. David Paterson announced late last week a suspension of the requirement for the current flu season. Here is coverage from the New York Times.

Notwithstanding the New York decision, many health systems are proceeding with influenza vaccination requirements this fall. The Immunization Action Coalition has compiled an "Honor Roll" of health care facilities with vaccination requirements for health care workers.

H1N1 roundup: international vaccine supply, nasal vaccine first in US, and more

Several H1N1 vaccine-related items in the news over the past few days:

• President Obama announced Thursday that the US would share 10 percent of its H1N1 vaccine globally, working with WHO. As this Associated Press story reports, the announcement is part of a joint effort by several western countries to improve access to H1N1 vaccine in the developing world. Here is the press statement from the White House, as well as a statement from WHO praising the announcement. This Washington Post story has more.

• Speaking of WHO, this Associated Press story published Friday reports that recent WHO projections of H1N1 vaccine production are "substantially less" than previous forecasts. Supply shortages further complicate the already-enormous challenge of large-scale vaccination against H1N1 influenza in the developing world. (A UN report leaked to the UK newspaper The Guardian presents a particularly ominous forecast of the impact of H1N1 flu in developing countries without a coordinated global assistance effort.)

• Here in the U.S., CDC announced Friday afternoon that 3.4 million doses of MedImmune's nasal spray vaccine (known as FluMist in its seasonal flu variety) will be the first H1N1 vaccine available. These doses should be available by early October, followed by the other (injected) vaccines throughout the month and beyond.
  

• Finally, Flu.gov, the U.S. government website launched several years ago as PandemicFlu.gov, completed a redesign and expansion on Friday. Billed as a 'one stop' for information on both seasonal and H1N1 influenza, the site summarizes its newly added features here.
  

Preparations intensifying for H1N1 mass vaccination program

A front page story in today's Washington Post ("Swine flu campaign waits on vaccine") highlights the increasing likelihood of an unprecedented mass vaccination program this fall against H1N1 influenza. Much is still unknown about the precise size and scope of the vaccination campaign, but, according to NIH's Dr. Anthony Fauci in the Post, "There's little doubt we're going to vaccinate people. Who and when and exactly how -- we have to figure out."

Answers to these questions will be learned in part from the ongoing clinical testing of the vaccine. According to a report in yesterday's New York Times, no serious side effects have been seen in the initial stages of H1N1 vaccine trials. As the Times reports, 4,500 research volunteers will receive the vaccine, making detection of any rare adverse events related to the vaccine impossible to detect during clinical testing.

CIDRAP News also reported this weekend on the status of H1N1 vaccine trials. According to an NIAID teleconference, preliminary data will be available by mid-September. Of particular importance will be data on the quantity of vaccine needed to provide immunity in a person, results that will impact the total number of doses that will be available in the fall.

Finally, the official recommendations from the ACIP regarding H1N1 vaccine priority groups were published electronically on Friday. The priority groups -- pregnant women, those in close contant with infants, health care personnel, children and adults under 24 years old, and older adults at risk of influenza-related complications -- were determined at a special meeting of the ACIP last month. Presentation slides from that meeting are available on the CDC website.

Seasonal flu: Record supply expected; FluMist approved for 2-4 year olds; Data shows low coverage in past

In what is becoming an annual tradition, CDC announced last week that a record supply of seasonal influenza vaccine is expected to be available for the approaching flu season. Once again, however, barring a massive increase in the number of Americans seeking the vaccine, millions of doses will very likely go unused.

As this AP story reports, current estimates are for 132 million doses to be available this year, an increase over last year's total of 121 million doses (itself a record). Despite the vaccine being recommended for 218 million Americans, 18 million doses were not used last year and were destroyed. Here's more coverage from CIDRAP News and the Washington Post.

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Last Wednesday, FDA approved FluMist -- the only flu vaccine that is administered nasally -- for use in children between the ages of 2-5. Previously, the vaccine had been approved for those age 5-49. Here's the FDA announcement, coverage from CIDRAP News, and a particularly detailed story from the Washington Post.

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Last week's MMWR included several papers detailing flu vaccination coverage in recent seasons. Here's state-by-state data of adults 18 and older, children age 6-23 months, and early data on children age 6-59 months (reflecting the new ACIP recommendation of June 2006). The editorial notes for all three papers explain that the observed vaccination rates are well below CDC goals.

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In related news, CDC announced a new-and-improved seasonal influenza website available at www.cdc.gov/flu/. The site contains extensive information for health professionals and the general public about the virus, prevention, and treatment.

Supply shortage expected for ProQuad vaccine

Following up on this post from March regarding possible shortages of varicella-containing vaccines, this announcement in MMWR last week alerted readers that Merck's ProQuad (a measles, mumps, rubella, and varicella combination vaccine) would be unavailable beginning in July through at least the end of 2007.

With varicella vaccine limited in supply, Merck is prioritizing production of its stand-alone chickenpox vaccine for children and its new shingles vaccine for adults -- both of which are varicella vaccines -- ahead of ProQuad. With its MMR vaccine still available, no children should go unprotected as a result of this temporary shortage, but an additional injection will be needed to provide full protection against the four infections, as this AP story on the announcement explains.

While this news is more of an inconvenience than a serious concern for physicians or patients, it does illustrate the vulnerability of a system in which a vaccine is produced by a single manufacturer, as is the case for many in the United States.

Potential supply issues for varicella-containing vaccines

Late last month, the CDC's MMWR included a "Notice to Readers" titled "Supply of Vaccines Containing Varicella-Zoster Virus." What are those vaccines? Varivax (against chickenpox), Zostavax (against shingles), and Proquad (a combination of MMR and chickenpox). All are manufactured by Merck, and no other U.S. companies manufacture vaccines providing protection against VZV.

There's no shortage to report, only news from Merck that the yield produced from early stages of the vaccine manufacturing process are less than expected (the reasons for which are not yet known). In the meantime, the plan is to prioritize production of the chickenpox and shingles vaccines, creating the potential for a limited supply of the combination ProQuad by late 2007. Again, not a major issue, as children can receive the same protection by receiving MMR and Varivax separately.

However, this announcement does remind us of the potential fragility of the U.S. vaccine supply. In addition to varicella-containing vaccines, those against measles, mumps, rubella, HPV, and rotavirus, among others, are all produced by a single manufacturer in the U.S. While the economic reasons behind this single-supplier market have been discussed by many, minor hiccups such as this announcement raise the attention of those who worry that the system is not sufficiently insulated against the risk, however small, of major production problems affecting a recommended vaccine.

Seasonal flu: Healthcare workers, surplus doses, and more

A number of items in the news recently regarding seasonal (i.e., 'regular') influenza:

• Following up on our earlier post about the importance of vaccinating healthcare workers against seasonal flu, this story in the Houston Chronicle details CDC efforts to increase vaccination rates among this group.

• Regarding flu supply, we've noted several times this fall the very large supply of vaccine doses expected to be available this year -- as many as 20 million more doses that have ever been administered in a single season. This New York Times story ("After Shortage, Vaccine for Flu Goes Unused," 12/16) and this Cox News Service story examine the problems posed by the early delays in vaccine shipments this fall and the doses likely to be wasted as a result.

• The December 14 issue of the New England Journal of Medicine included three papers on flu vaccination. One article compares the efficacy of live attenuated flu vaccines (i.e., FluMist -- the nasal vaccine) vs. inactivated vaccines (the others that are injected). Another paper studies school-based vaccination programs, and a third is an editorial titled "Different approaches to influenza vaccination". All three papers are nicely summarized in this story by CIDRAP News' Lisa Schnirring.
  

'06 flu vaccine supply might set records

During our Labor Day publishing hiatus, good news came from CDC that the total supply of flu vaccine for the upcoming flu season may reach an all-time high. The headline is that more than 100 million doses are expected to be available by late fall, a number that could reach as high as 115 million if a new vaccine from ID Biomedical (part of GSK) is licensed in the near future, as is anticipated. Either estimate would easily surpass the previous all-time high of 83 million doses administered in a single season.

Here's the detailed CDC press release as well as the related news story from CIDRAP. Between the impressive supply forecasts and the expected arrival of a fifth vaccine, signs suggest that at least some lessons were learned from the Chiron-induced flu vaccine shortage of 2004. The next challenge will be working to ensure that those 100+ million doses are administered, particularly to those groups identified as high-risk populations.

Evaluating the adequacy of pediatric vaccine stockpiles

While the Chiron-induced flu vaccine shortage in 2004 received far more public attention, there have been a number of shortages of universally-recommended pediatric vaccines since 2001. Among the vaccines in limited supply at some point in the past five years are measles/mumps/rubella, varicella, and diphtheria/tetanus/pertussis, among others. There's little doubt that the likelihood of temporary shortages is increased by the presence of only a single manufacturer of many recommended pediatric vaccines. Ensuring an adequate supply of those vaccines recommended to be administered to all children is very much an ethical issue.

The reasons for the current shape of the U.S. vaccine marketplace are many and well documented elsewhere. While some may hope for a wholesale redesign of the vaccine production marketplace, a more immediate response implemented by the CDC has been the creation of a 6-month stockpile of many recommended pediatric vaccines. The stockpile is intended to provide a buffer against short-term disruptions.

The current issue of Vaccine has an interesting paper that examines the adequacy of current stockpile levels to respond to shortages. The paper is titled "Stockpile levels for pediatric vaccines: How much is enough?" (free abstract, subscription required for full text). Using mathematical modeling, the authors' data validate the belief that current levels are adequate for a 6-month shortage of the vaccines included in the stockpile. Not surprisingly, the current stockpiles are very likely too small for a shortage of 8 months or longer, depending on how severe the shortage is. It should be noted that most recent pediatric vaccine shortages have lasted over one year.