24 November 2009

H1N1 Impact

My daily email from ACEP tells me that the H1N1 influenza epidemic has finally peaked and is tailing off.  That is consistent with what we are seeing in our ER at the present time.  We got hit a little bit in April and more in May, but then seriously slaughtered in October, as you can see from the chart below, provided for all you data junkies:

From the beginning, 2009 was shaping up to be a banner year.  2008 had represented our high-water mark with 290 patients per day on average.  We were well ahead of that pace even before the emergence of the swine flu, with Feb-April all at record volumes.  You see the first true peak was in May when influenza (and the public fear of influenza) first became widespread. Things tapered off over the summer (if by "tapered off" you mean "remained at historically high levels).  Then we got the next peak in October: it was the first time we have ever seen 10,000 patients in a month.  We averaged 325 patients/day, 12% above our old baseline, and had peak days of about 390 patients, a full 33% above the old baseline.  The acuity remained reasonably low; at any given time, on average, we have had 12-15 inpatients with influenza.  Some of them, however, have been quite sick, and there have been a few young, healthy people who have been critically ill with influenza, which is very sobering.  Year-to-date, we are on pace for 112,000 patients, a 7% increase from 2008.

Operationally, I couldn't be prouder of our team.  They handled the historic influx of patients with aplomb.  Despite the fact that we felt that we were at maximum capacity before this all began, they took on the challenge and kept things running smoothly.  Our LWBS rate remained below 1%, and the door-to-bed time actually decreased from 9 minutes to 7 minutes.  It has been an amazing performance in trying circumstances.  Our processes that we have put in place held up beautifully, but it was without doubt the people behind the processes that made it possible for us to get through this epidemic successfully.

I'll be interested to see if there is a "third wave" of H1N1 in the late winter, when seasonal influenza usually peaks.  Perhaps it will just be predominantly the seasonal flu strains, or perhaps they will blend into one another.  I'm still anticipating a worse-than-usual flu season, but if the vaccine supplies ever do catch up, it may mitigate the outbreak somewhat.

On a slightly related note, there are now being reported outbreaks of Tamiflu-resistant H1N1:

CIDRAP >> Clusters of resistant H1N1 cases reported in UK, US
Nov 20, 2009 – Health officials in Wales today announced the identification of a cluster of patients in a Cardiff hospital who are infected with oseltamivir-resistant pandemic H1N1 influenza.

Also today, Duke University Medical Center in Durham, N.C., reported that oseltamivir-resistant H1N1 viruses were found in four very sick patients hospitalized there over the past 6 weeks. A Duke press release said all four patients had been in the same hospital unit, but it did not specify how many were there at the same time.

In Wales, the National Public Health Service (NPHS) said five patients in a unit at the University Hospital of Wales that treats people who have severe underlying health conditions have been diagnosed as having oseltamivir-resistant pandemic flu, and three of them appear to have been infected in the hospital.

Up to now, just one probable instance of person-to-person transmission of oseltamivir-resistant H1N1 flu has been reported. In September the US Centers for Disease Control and Prevention (CDC) reported oseltamivir-resistant pandemic H1N1 flu in two girls who stayed in the same cabin at a summer camp in western North Carolina.

Note to Dr Feelgood: this is why we don't hand out Tamiflu to every poor sucker with a fever and bodyaches.


Ron said...

H1N1 really alarmed the globe. Nowadays, all we need to do is to be so careful and watchful to avoid this disease. We can also have a test using ELISA kit.Many ELISA kit manufacturers are now occurring because of its advantages.

Anonymous said...

Most all of the parents I have talked to on the phone with children who have been given Tamiflu - stop the drug anyway mid-treatment due to side effects. That is how we get the resistant bugs too.....