Tuesday, September 15, 2009

The Pneumococcus vaccine - I am confused and alarmed, but a bonus for Pfizer-Wyeth or GSK?

So Minister has now agreed to putting the Pneumococcal vaccine into our National Childhood Immunization Programme, despite being resistant to the idea 2 years ago. At that time MOH said the situation did not warrant it.

"The ministry has reviewed our local situation and has decided not to incorporate the pneumococcal vaccine into the National Childhood Immunisation Programme at this point in time," said an MOH spokesperson. This is because the hospitalisation rates for invasive pneumococcal disease in children in Singapore declined from 38 per 100,000 people aged five years and below in 2004 to 26 per 100,000 people last year."

The latest figures Minister cited yesterday was that the annual number of cases was about 70.

I have to say I am somewhat puzzled. Did the situation deteriorate so rapidly over a mere 2 years? I mean we were in the pink of health 3 years ago, and then suddenly things appear to have worsened to the extent that now we need to immunize.

I did a quick check of the MOH epidemiological stats. Strangely MOH didn't publish any invasive pneumococcal stats until 2009..... so I am presuming MOH did collect data except that they did not publish. The 2009 data is however very interesting in that in the first 36 weeks, MOH logged an even more astounding 183 cases of invasive pneumococcal disease. Extrapolating to the full year, we might be looking at something like 250 cases!!! This is more than 3 times the estimate of 70 that Minister Khaw cited.

Quite frankly, I find the figures rather confusing. Do we have a problem or do we not have a problem? We had a declining incidence of 26 per 100000 per year in 2006. Minister cites 70 cases per year. And the MOH bulletin reports an approximate annual incidence of invasive pneumocaccal disease of 250 for 2009. All in a space of 3 years. Mind boggling to say the least. Or did I make a mistake with the figures?

Meanwhile Pfizer-Wyeth must be rubbing their hands rather gleefully if MOH implements the programme. Pfizer was rumoured to have bought Wyeth because (at least one of the reasons) because of the Prevnar vaccine that Wyeth had, plus the new 13 strain vaccine that is about to come on board. The size of the Prevnar market for Wyeth has been estimated to be about US$2.4 billion, and that of the new vaccine will probably exceed that.

But Pfizer-Wyeth has competition in the wings, as GSK has set up a S$600 million plant in Tuas to make pneumococcal vaccines!! This will be ready in 2011.

So the market hots up. I wonder who MOH will choose to supply the vaccines for the NCI Programme? I wonder who will get the cake?

Meanwhile parents have to be prepared to fork out approximately $700 for the vaccines ($170 per dose x 4 doses). And yes, taking from Medisave is still paying for it.


angry doc said...

It's worse than that, actually - being in the National Childhood Immunisation Programme means the vaccine is free.

I am guessing that the increase in cases is due to more diligent reporting on the part of the paediatricians - they have been calling for more vaccines to be added to the Programme for a long time now.

In any case, 250 invasive diseases a year is still about $20,000 to prevent one case?

gigamole said...

Actually I think they made clear that it is not free. Hepatitis and now pneumococcal vaccines are not free although they are included in the NCIP. I think this means all parents need cough up $700 from Medisave.

To be fair, I think mortality is only one extreme outcome....the idea is also to reduce the morbidity associated with invasive infections. Whether or not mass immunization is a cost effective solution is uncertain.

angry doc said...

I see.

$20,000 is per invasive disease. Assuming one mortality per year at 30,000 courses per year (birth rate), it works out to... $20 million per life saved?

gigamole said...

sorry....I don't follow. How did you get the $20,000 to prevent one case?

Estimated amount spent on vaccines (don't count manpower etc etc) wil be live births x cost of vaccines...
= 30000 x $700 = $210000

That estimated annual expenditure will, at steady state, 'save'....
one fatality per year,
prevent 250 (all ages )pneumococcal admissions,
or 70 (<5yrs) pneumococcal admissions

I think that's right.

But then again, I am quite mathematically challenged.

Plus I am only an amateur epidemiologist. :)

angry doc said...

30,000 births x $170 x 4 = $20,400,000. (you missed out one zero)

$20,400,000 / 250 invasive cases = $81,600 / invasive case.

My error.

angry doc said...

In fact, you missed out 2 zeros!

gigamole said...

Touche.....! :)

Told you I was mathematically challenged.

It will probably work out cheaper cos there will be economies of scale. But on the other hand, if we go for the 13 strain vaccine, it may be priced higher.