Comment by resolutebat | Hacker News Reader

Comment by resolutebat | Hacker News Reader

A few years ago I had dengue in Singapore, and while my case was mild as far as these things go, I was still almost hospitalized because my platelet counts dropped so low. The overall experience was sufficiently unpleasant that I was strongly incentivized to take Dengvaxia, the only currently approved vaccine, but having gone through the process, I can see why very few people do.

- As mentioned in the article, if you have never had dengue and you take Dengvaxia, it paradoxically increases the odds of getting a bad case. So in Singapore you're only eligible if you have had a confirmed positive blood test for dengue previously.

- I had incredibly good health insurance at the time, which among other things happily paid for my dengue management at one of the best private hospitals in the country ($$$), but they straight up refused to cover Dengvaxia and I had to pay over $700 out of pocket.

- Getting the vaccine required 3 shots spaced several months apart. Not a huge problem for me, and side effects were minor to non-existent (much better than eg COVID vaccines), but obviously this reduces compliance.

- Even in Singapore, which is a wealthy, dense tropical country with a lot of dengue and thus eligible people, the hospital (again, one of the largest and best-resourced in the country) had to special order the vaccine every time for my three visits and there were a couple of minor hiccups with deliveries etc.

My reward for all this is not immunity to future cases of dengue (remember, there are 5 serotypes and getting it once only makes you immune to that variety), but a 80% reduction in the odds of getting severe dengue the next time around. Which is nice, but not a game-changer.

I got Dengue on a business trip to Bali a number of years back from the US. Got a very high fever upon return to the US and ended up in the emergency room because of crashed platelets (which never fully recovered) and white cells. Was impressed the on-call infectious disease guy (in New England) immediately made the call about what it was--my primary care guy had no idea. Cost me something like $1K in spite of good insurance between ER and blood work that had to be sent off to Paris and basically zero treatment. Vaccine isn't indicated for my situation but it basically makes me hesitant to ever travel to Dengue-prone areas of the world again.

> one of the best private hospitals in the country ($$$)

It's possible you might've gotten faster, better, and cheaper treatment at the Communicable Disease Centre which might already have had a stock of Dengvaxia.

Like you said, dengue is endemic to Singapore, and most people who get it go there to get treated, rather than the (very expensive) private hospitals.

My understanding is that the unsubsidized cost of the three vaccine doses is on the order of $600, so the markup was pretty minimal here. (IIRC my insurance did cover the initial consultation re: the vaccine and the nurse fees.)

I am from Argentina where dengue is an epidemic right now (we had it for years but it seems this year is worse), and what everyone says about the vaccine is exactly this:

> it paradoxically increases the odds of getting a bad case

So what is it good for?

The clause preceding that quote gives you the answer:

> if you have never had dengue and you take Dengvaxia, it paradoxically increases the odds of getting a bad case

e.g. if you have had dengue previously, it reduces your chances of having a bad case to 20% (according to that comment).

And, critically, once you have one serotype of dengue, your chances of severe dengue from infection by another serotype are substantially higher.

First dengue is often not that bad. Second dengue is often quite bad. This vaccine makes second dengue not that bad, but if you take it without having had first dengue, it just leaves you in the same boat as if you’d had first dengue — worse off than if you’d had no dengue.

Can confirm this. The second attack is potentially fatal.

> but a 80% reduction in the odds of getting severe dengue the next time around. Which is nice, but not a game-changer.

As far as I know if you get Dengue twice, and in the "wrong" order of serotypes, you are very likely to die. That should make the vaccine a game changer if it works like you describe.

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