Child deaths from flu + MRSA: CDC confirmation

Hello again, constant readers. It's been an exciting few weeks at Casa Superbug. I'll spare you the details — most of them are both grueling and trivial — but out of the murk, here is a piece of excellent news: SUPERBUG has been edited, revised and sent back to the publisher, who has sent it into production. Yes, it's actually beginning to become a book. There are many more steps to go, but it it is finally, really on its way.

Meanwhile, there is a ton of MRSA news to catch up on, which I will roll out over the next week or so. First: For those of you who don't read the CDC's weekly bulletin (called the MMWR, for Morbidity and Mortality Weekly Report. It's the best-read magazine you've never heard of. It's free. Go already), there was an important and disturbing report last Friday, reporting the case details of children who have died from H1N1 flu.

As of August 8, the CDC said, 477 people had died in the US from H1N1, and 36 of them were children and teenagers. Out of those 36:

• 7 were younger than 5
• 24 had at least one high-risk medical condition, many of them neurological (developmental delay, cerebral palsy) or pulmonary; 12, or one-third, did not
  
• 23 had some pathologic analysis done during their illness or after their deaths
• 10 had bacterial co-infections
• of those 10, 5 had staph infections
• 3 of the staph infections were MRSA.

Let's bring the first and last terms of that equation together: 36 children; 3 known MRSA infections. Though it could be an underestimate (because 13 children had no pathology done), that is a non-trivial 8%.

The report splits the data on the child deaths a number of different ways, and reveals details that are important to note. Six of the bacterial infections (four staph) were in children older than 5 who did not have any underlying conditions; they were healthy, normal kids before developing flu. Of the 7 kids younger than 5, 2 had a bacterial infection; again, neither child had a high-risk condition.

How worrisome are these numbers? It's hard to say with precision, but they are certainly not good news. The CDC has only been counting child deaths from flu for a few years, and the totals they have come up with are very variable: 153 in 2003-04, 47 in 2004-05, 46 in 2005-06 and 73 in 2006-07. But, important point: Those deaths were during the regular flu season, which goes from roughly October to March. These new deaths occurred between late April and early August, when there is not supposed to be any flu. What this will mean for this fall and winter, when H1N1 will still be around, and may co-circulate with seasonal flu, no one yet can say.

For our purposes, the most important point is that lethal MRSA co-infections are now confirmed to be happening in the setting of H1N1 flu. And, as the CDC paper notes, these infections happened in children who would not have been expected to have a tough course, because they had no underlying high-risk conditions:

This report also highlights the prominence of laboratory-confirmed bacterial coinfections, which were identified in 10 (43%) of the 23 children who had culture or pathology results reported. All six children who were aged ≥5 years, did not have a high-risk medical condition, and had culture or pathology results reported had an invasive bacterial coinfection, suggesting that bacterial infection, in combination with 2009 pandemic influenza A (H1N1) virus infection, can result in severe disease in children who might be otherwise healthy. Clinicians should be aware of the potential for severe bacterial coinfections among children diagnosed with influenza and treat accordingly.

Obviously those of us who are concerned about MRSA and the potential for MRSA pneumonia alongside flu have been worried about this (long archive of posts here). If there is any good news in the sad saga of these deaths, it is that the CDC has confirmed that MRSA pneumonia in H1N1 flu is a real and dangerous possibility.

So if you are concerned about this, first, bookmark the MMWR report, because it will be something to show to a physician if necessary. And second, keep in mind the potential for pneumonia if you have a young child who contracts H1N1. I am not suggesting being alarmist; if H1N1 circulates widely, doctors and ERs will be overwhelmed, and we should try not to add to their case load unless really necessary.

But on the other hand, if a child has chest pain or breathing difficulty, don't hold back. There are online tools such as this one by Children's Healthcare of Atlanta that can help a worried parent assess whether and when a child with flu should be taken to the ER. If you click through its steps, you'll see that breathing difficulties and the possibility of pneumonia are things that it takes seriously, and so should we.