Daily hospital admissions plateau: are we still yet to see the peak?

27 08 2009

So maybe I was premature yeaterday in calling a peak for the first phase here in Oz. Today I finally got around to graphing daily hospital admissions of people with Swine Flu. And, as you can see, this graph isn’t really showing a peak yet.

Just to be clear: this graph is the 7 day moving average of new daily admissions to Australian hospitals of people who have tested positive to Swine Flu.7 day move avg hospital admissions

The graph is basically still flat – with no decline to speak of, that I can see. Over the last two months it’s varied between 90 and 50 admissions per day, and right now is basically back at its average of 74 admissions per day. We’re plateauing – but we’re not declining.

As I said yesterday: Are we at the peak? I don’t know. Let’s see what the next week brings.

(As always you can click on this graph to blow it up for a closer look. Then click the back button on your browser to get back to this post).


Should we call the “peak” on the first wave here in Oz?

26 08 2009

So, have we seen the peak of the pandemic (or at least of the first wave) here in Oz in the last week? I suspect we have. I’ve updated the key graphs with numbers for the last week and they seem to be starting to tell that story.

Here is the 7 day moving average of new cases being reported each day. We are now at a level (of about 300 new cases being reported per day) that we haven’t seen since early July:

7 day move avg australiaAs with all the graphs – you can click on this graph and blow it up to full screen for a better look.

Now have a look at the second graph. This is the 7 day moving average of deaths reported each day of people with swine flu. Again, the trend has been down, and we seem to have formed a clear peak in the last week.

7 day move avg deaths

The only graph that’s not shifting yet – that’s still just “plateaued” is the number of people currently in hospital with Swine Flu:

aust hospitalisationsWe have had one of the mildest Augusts ever all along the east coast of Australia this year – and that may have brought this peak forward earlier than many expected. Let’s see what the next week brings…

August 17th update

17 08 2009

Here are the graphs for the August 17th update from the Department of Health and Ageing. Spring feels like it has arrived early over the last few days (at least here in Sydney), but I’m not going to call a peak yet. I’m updating the Australian graphs page as well, but remember you can expand these graphs for easier viewing just by clicking on them.

7 day move avg australia

aust hospitalisations7 day move avg deaths

Moving average of daily deaths may give a good indicator of the progress of the pandemic

12 08 2009

I’ve been thinking about how we map the progress of the pandemic here. The Department of Health and Ageing’s daily confirmed cases are good – but we all assume they understate the true number of Swine Flu cases out there by 1 to 2 orders of magnitude. Why? Because the overwhelming number of people who get Swine Flu are not being tested and so never show up on the figures.

So, the risk with these figures is that we may get a fall off in daily new cases and therefore think we have hit the peak of the pandemic, when in fact all that has happened is that testing protocols have been changed.

In other words, we need measures that are not so affected by human decisions. One of those measures, I think, is the number of people dying with Swine Flu each day in Australia. That’s a number that is not going to be affected by decisions on testing, I assume. (If you’re that sick, they’ll test you. The only issue here is that in a normal flu season they might not test you, and simply put down your cause of death as pneumonia, but in a pandemic, my guess is that they will test). So, if we see this measure peak and start to fall sustainably, we can be pretty sure we’re over the hump of the pandemic and coming down the other side.

So, I’ve graphed the seven day moving average of daily deaths of people with Swine Flu in Australia. Note, I’ve said deaths 7 day move avg deathsof people with Swine Flu, not because of Swine Flu. These people have died and they had Swine Flu at the time – but that doesn’t tell us that it was Swine Flu that was responsible.

Anyway – here’s the graph. And as you can see, at the moment, on average, 3.7 people are dying each day in Australia with Swine Flu. That’s the highest it’s been since the start of the pandemic here, and it is showing no sign that we have reached the peak yet. Remember that you can click on this graph to blow it up.

I’ve also updated my usual two graphs with the latest figures from the Department of Health and Ageing. Here they are (clicking on these graphs will blow them up):

7 day move avg australiaaust hospitalisations

August 11th update: when is a peak not a peak?

11 08 2009

When is a peak not a peak? When it’s a plateau. Well maybe..7 day move avg australia. Anyway – here is the latest 7 day moving average graph. We seem to be bouncing around the 600 new confirmed cases per day at the moment.

The feeling of flattening out is confirmed by the lack of movement in the current figures for people who are currently in hospital with Swine Flu. No let up there. We seem to get as many new admissions as there are discharges every day. (I hope taust hospitalisationso get the new admission figures worked out over the next few days).

Anyway, here’s the latest graph on people currently in hospital. For a full explanation of these graphs, have a look at the Australian Graphs page at the top of this blog. If you want to have a closer look at the graphs, just double-click on them.

How does this flu season compare with others?

10 08 2009

Just how much worse is this flu season here in Australia, compared to other seasons? I’ve looked at this question twice before, over the past few weeks (see here and here for good background). Well it’s time to take another look – because the numbers are in for July 2009.

As I’ve discussed before, the Department of Health and Ageing have a “notifiable diseases report generator” that will give you a table of disease notifications, which is then easy to graph. So, I’ve run this generator for influenza notifications and got some interesting stats.

The first graph (below) shows the number of influenza notifications in Australia for the years 2001 to 2008 (8 years all up), by month. At each month in this graph I show three points:

  • The bottom point is the minimum value for this month over the 8 years. In other words, I look for the year that had the lowest number of flu notifications for that month, and that’s the figure I plot. For example, if I choose the month of July, the year with the fewest notifications for flu was 2004, with only 96 notifications being made in the July of that year. So, I plot 96 as the minimum point for July.
  • The top point is the maximum value for the month. For example, for the month of July, the year with the most notifications was 2007 (of all the July’s from 2001 to 2008). In that year, July clocked up 2,470 notifications. So that’s the number I plot for maximum.
  • The middle point for each month is the average number of notifications for that month over all the years 2001 to 2008. So, for July we got an average of 770 notifications in that month for the years (2001 to 2008). So I plot 770 as my average.

Note that these are notifications for all types of flu (not just swine flu, which wasn’t around in its present form anyway):

year on year comparisons 2001 to 2008

You can double click on this graph to expand it.

The graph tells an interesting story (as I’ve remarked before). Flu notifications tend to peak in August. And there’s still a lot of flu notifications in Australia in September (on average, more than in July). In other words – we are not through the worst of our normal flu season yet.

The next graph then becomes very interesting. All I’ve done is included 2009 monthly notifications in the above graph, as a fourth (purple) line. I’ve changed the scale to fit 2009 in. Here it is (again, you can double click on it to expand it):

year on year comparisons 2001 to 2009I think this graph tells the story well enough as to just how bad this season is compared to a normal season. The only caveat I would add to this is that we have clearly undertaken a lot more testing for flu in Australia this season than in a normal season. So some of the marked increase in notifications has to be due to an increased testing effect. Just how much – I don’t know.

August 10: numbers bounce back

10 08 2009

As I suspected, rumours of Swine Flu’s demise over here may have been overstated. The 7 day moving average of confirmed new cases has bounced back, with new figures released for the weekend and today by the Department of Health and Ageing. Also – hospitalisations continue to stay at their high levels. Have a look at the graphs below. You can double click on them to blow them up:

7 day move avg australiaaust hospitalisations