More on MRSA and the new flu

Constant readers, I admit it: I am a bad blogger. The wave of news on the novel H1N1 (AKA the Virus Formerly Known as Swine) has been just overwhelming. Apologies for disappearing.

Out of the crashing surf, though, I picked up an interesting tidbit that speaks to our concerns about MRSA. Here's some background: If you have been following the swine flu story, you'll have noticed that one of the puzzles has been why the Mexican experience has been so different from the United States or from the other countries where this flu has appeared briefly. (North America so appears to be the only area in which there is sustained transmission.) Among the hypotheses:

• There is a difference in the medical care that victims are receiving.
• There is a statistical artifact: The serious cases are a tiny percentage of the mild cases, and the US has not seen enough cases to, probabilistically, experience significant serious cases yet.
• Or, corollary to the above: Mexico has many more cases than its surveillance systems have been able to count, and that is why we have seen that (unknown but presumably tiny) percentage that become serious cases appear there but nowhere else.

(For more on this, here's a CNN story from a few days ago, quoting me and people much more distinguished than me.)

But a commentary by a global-health expert raises another hypothesis, one that brings this outbreak around to our concerns: the possibility that the serious flu cases in Mexico are being complicated by secondary pneumonia caused by MRSA or other bacteria.

We've talked about this issue before (see this post about the importance of MRSA in a flu pandemic and this paper by, among others, Dr. Anthony Fauci, director of NIAID, and Jeff Taubenberger, PhD, co-discoverer of the virus of the 1918 flu). MRSA pneumonia secondary to flu infection is the etiology of the necrotizing pneumonia cases that kill children very quickly, and is the reason why I keep haranguing you regarding flu shots.

Is bacterial pneumonia playing a role in the current epidemic? It's too soon to tell; there is not sufficient clinical data. But it is an interesting speculation and one that we should keep in mind as this goes forward.

For a moment, a different pathogen: swine flu

Constant readers, some of you know that I have a long history of covering pandemic flu (I wrote the first story in the US media about avian flu back in 1997, and covered pandemic preparations for years). I've had that somewhat on the back burner while I worked on this MRSA project and handled some personal family matters, but with the book manuscript almost completed and the family stuff ending, looks like I will be covering flu again.

For now, let me direct you to some resources:

• My colleagues at the news site of the Center for Infectious Disease Research and Policy are doing yeoman work with very few resources. Some of you many know CIDRAP as home base of Michael Osterholm, PhD, advisor to several administrations on pandemics and disasters and pandemic-flu interviewee on Oprah. The CIDRAP site includes a series I wrote about 18 months ago now that explains why it will be so hard to achieve a flu vaccine in time for the start of a pandemic.
• Helen Branswell of the Canadian Press is the most connected flu reporter on the planet; because she is at a wire service, there is no one page to send you to, but Google her name, or follow her on Twitter @diseasegeek.
• My fellow global-health reporter Christine Gorman, formerly of TIME Magazine, has put up a thoughtful post with many links on her blog Global Health Report.
• There are seriously good flu blogs (also in the blogroll) at Effect Measure, H5N1, Avian Flu Diary, Scott McPherson's Journal, A Pandemic Chronicle and the indefatigable preparation-conscious groups bloggers at ZoneGrippeAviare (in French and English).
• University of Iowa epidemiologist and zoonotic-disease expert Tara Smith, PhD., is blogging thoughtfully at Aetiology.
• Several years ago I helped conduct a conference at Nieman House at Harvard, the home base of the Nieman Foundation and fellowships, on understanding and getting ready to cover pandemic flu. The materials are here.

That's all for now. More soon, I expect on both MRSA and flu.

Five-fold increase in flu+MRSA deaths in kids

I have a story up this evening at CIDRAP News about a new paper in the journal Pediatrics that analyzes the incidence of child deaths from pneumonia caused by the combination of MRSA and flu, a sad and scary development that we've talked about here, here and here.

(NB: CIDRAP News is the original-reporting and news-aggregation arm of the Center for Infectious Disease Research and Policy at the University of Minnesota, an infectious disease research center headed by noted epidemiologist Michael Osterholm, PhD. I have a part-time appointment there. CIDRAP News is the best-read infectious-disease website you have never heard of, with about 10 million visitors a year, and is a notable resource for news on seasonal and pandemic flu, select agents and bioterrorism, and foodborne disease.)

It is bad netiquette and not fair use to reproduce another publication's entire story here, even if I wrote it. Here though are the highlights:

• 166 children died of influenza in the past three seasons (2004-05, 2005-06, 2006-07) according to 39 states and 2 local health departments (86 this year in preliminary reporting)
• The proportion of deaths from bacterial co-infection rose each year, from 6% to 15% to 34%, a five-fold increase
• Almost all of the bacterial co-infections were staph; 64% of them MRSA
• The rapid rise in MRSA colonization (from 0.8% of the population in 2001 to 1.5% in 2004 — that's more than 4 million people) may be playing a role
• And, some of these deaths could have been avoided if children had had flu shots — but overall, only 21% of under-2s and 16% of 2- to 5-year-olds get the two shots they need to be fully protected against flu.
  

Please click through to CIDRAP for more.

The cite is: Finelli L, Fiore A, Dhara R, et al. Influenza-associated pediatric mortality in the United States: increase of Staphylococcus aureus coinfection. Pediatrics 2008;122:805-11.

The importance of MRSA in a flu pandemic

Constant readers will know that, in another part of my life, I write a great deal about seasonal and pandemic influenza, a subject I've been following since writing the first story in the American media about avian influenza H5N1 (in August 1997; find it on this page.)

And people concerned about MRSA realize that flu and MRSA have an important overlap: For decades, long before the emergence of MRSA, staph was one of the most important contributors to secondary bacterial pneumonia, which occurs after the flu virus has damaged the lung tissue and allows staph and other bacteria to take hold.

In the past few years, we've been reminded of this interaction because of the shocking rise in cases of necrotizing pneumonia caused by MRSA (blogged here and here). Twice in the past two years, the CDC has asked state health departments to report any cases of flu/MRSA co-infection; in the 2006-07 flu season, 22 children died from MRSA necrotizing pneumonia secondary to flu.

Comes now one of the giants of staph research to warn of an unconsidered danger of MRSA: as a contributor to deaths in a flu pandemic. Dr. Theodore Eickhoff, who wrote some of the earliest papers on hospital-acquired staph infections, has written an assessment in Infectious Disease News of two new pieces of research into deaths during the 1918 flu pandemic. Both papers contend that it was bacterial pneumonia that was the major killer in that global storm of death, and not the novel flu virus itself.

Eickhoff looks forward from those findings to consider what havoc a new pandemic could wreak in this era of massive MRSA transmission. He contends that national planning for pandemics — a huge effort and expense for the US and other governments over the past few years — has paid insufficient attention to the possibility that bacterial infection will be as significant a danger as whatever new flu has emerged:

Authors of both of these reports point out that their findings have important implications for pandemic preparedness today. U.S. preparedness policy, and indeed that of almost all other countries, has been focused on preventing or modifying influenza virus infection itself. Thus, vaccine development and anti-viral drugs (eg, neuraminidase inhibitors) have been the major efforts, and a great deal of stockpiling has already taken place. Clearly it is equally necessary to stockpile antibiotics effective against primarily community-acquired organisms causing post-influenza pneumonia today, including both MSSA and MRSA. Much more consideration needs to be given to the possible role of pneumococcal and possibly other bacterial vaccines as part of pandemic preparedness.

Cautionary tale: Unintended consequences, ripple effects

New story by me, up at the news website of the Center for Infectious Disease Research and Policy, where I am a contributing writer. It's on flu, not MRSA, but it contains lessons that apply to MRSA too.

Gist: This flu season turned out unexpectedly badly, with physicians across the country saying offices and ERs are overwhelmed with very sick patients. In ERs in particular, the dominos fall like this: More patients than usual come in for help; with some of them seriously sick, other patients get pushed further back in the triage queue; while the seriously sick wait in the ER for hospital admission, other patients back up in the waiting room; diversion (turning ambulances away) is called to relieve some of the pressure; and patients are taken instead to another ER, where the process begins again.

The irony here is that flu is an at least partially preventable disease: Under normal circumstances, get a flu shot, sharply reduce your chance of getting the flu. However, this year the flu vaccine and the circulating flu strains don't match well, and many people who stepped up and got the shot still developed flu. And why did the shot not match? It was partly a failure of luck — flu's perpetual genetic drift is unpredictable — but it was also a failure of infrastructure: Federal health planners knew a year ago that one strain was drifting, but that virus didn't grow well enough under lab conditions to get an isolate to vaccine manufacturers in time for it to be included in last fall's vaccine. (See Dr. Nancy Cox's comments in this CDC press briefing; the FDA discussions she refers to are archived here.)

And why did it have to be given to the manufacturers a year ago? Because it still takes 6 months to make commercial quantities of flu vaccine, using a technology that is essentially 50 years old. This despite either 10 years or 32 years of concern over the possibility of a flu pandemic (depending on whether you start counting from the appearance of avian flu H5N1 or the aftermath of the 1976 swine flu).

And why is any of this of concern for MRSA? Because many researchers and clinicians say that the only way to combat MRSA effectively is with a vaccine. Improving flu vaccination has been top of the public health wish-list, and a target of significant government funding, for years now, and yet it is still a disappointing mess. What chance for a lower-profile MRSA vaccine?

And to Scott McPherson for the bloglove hat-trick!

Journalists aren't really accustomed to people liking us, so I'm a little dizzy. But huge thanks also to Scott McPherson, who was sweet enough to mention my first book, on the CDC's outbreak SWAT teams. Scott's day job is in the thick of politics — he's the chief information officer for the Florida House of Representatives — and he regularly nails the disconnect between public-health policy and the messy real world. Read him here.

And also to Crawford Kilian's readers!

Crof, dean of avian-flu bloggers and indefatigable proprietor of H5N1, very kindly called this "an excellent new site." To have the support of such experienced bloggers is a wonderful thing.

Big welcome to FLA_MEDIC's readers!

The energetic and always-thoughtful proprietor of Avian Flu Diary very kindly called out this blog today. (In the intro box over on the right, I invited reading by MRSA researchers, MRSA victims and major disease geeks — he says he's No. 3.) So welcome to anyone who found there way over here from there. And if you haven't been to his blog yet, go now: His essays and analyses on the possibility of pandemic flu are always worth reading.