Sri Lanka Is Declared Malaria Free by World Health Organization | Hacker News Reader

Sri Lanka Is Declared Malaria Free by World Health Organization

blogs.wsj.com

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Sri Lankan here. We're not exactly celebrating because within the last 10 years, cases of dengue fever has risen from about 9000 to 32000:http://www.dengue.health.gov.lk/index.php/information-on-den...

Another interesting thing: when DDT was banned in the 1960's, Sri Lanka's malaria cases went from 17 to half a million: http://scienceblogs.com/deltoid/2005/02/17/ddt3/

The pull back from DDT has had all kinds of devastating effects. For instance, bedbugs are an actual fear now, for the first time in ages.

But there has been outrage about the effects of wealthy nations that drew the benefits of DDT before banning it (like, getting rid of malaria) and now putting pressure on poorer nations to _not_ use DDT, and suffer the consequences.

http://mobile.nytimes.com/2004/04/11/magazine/what-the-world...

Did you read that link? DDT doesn't work and it's toxic, making it a terrible choice.

WHO suggests DDT is safe and effective to use indoors to combat malaria: http://www.who.int/mediacentre/news/releases/2006/pr50/en/

"Indoor residual spraying is useful to quickly reduce the number of infections caused by malaria-carrying mosquitoes. IRS has proven to be just as cost effective as other malaria prevention measures, and DDT presents no health risk when used properly.”

What people consistently fail to take note - Malaria is an absolutely terrible disease, killing over 1 million people/year, so even if DDT was toxic (which it's not) and only marginally helpful (Also which it's not, very helpful indoors) - it would still be worth using if it could reduce the fatality rate by even 1%. That's 10,000 human lives saved. And that doesn't even include the 200 million plus people who suffer from Malaria.

But given that DDT is neither toxic, nor ineffective, it should be used wherever appropriate.

Not toxic and not ineffective? Did you read the WHO link or see what lead to them not using DDT in Sri Lanka? There is no shortage of evidence that DDT is bad for human, that's hardly debatable (and read what you posted, it doesn't say it's safe). What is debatable is the cost benefit ratio. How many pre terms births, cancers, sterile males etc are worth it for the reduction in malaria. Edit: http://www.thelancet.com/journals/lancet/article/PIIS0140-67...

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1241918/

http://press.endocrine.org/doi/10.1210/jc.2015-1841

Not sure what I can do help you see this differently. I thought, DDT presents no health risk when used properly. was pretty straightforward.

There are a lot of important things in the world, that are absolutely essential to human health, such as DEET, which has warnings like, Ingestions of DEET have been associated with nausea, vomiting, hypotension, encephalopathy, seizure, coma, and ataxia., Ingestion of 50 mL of 100% DEET by a 33 year-old woman resulted in hyptotension, coma, seizures and death. Ingestion of 25 mL of 50% DEET by a one-year-old child resulted in coma and seizures. - but nobody in their right mind would suggest we not use DEET just because it can have negative impact on human health. It's pretty much the key to reducing mosquito bites.

Widespread outdoor spraying of DDT has some pretty significant negative effects on the environment. But there is much less debate about the cost/effectiveness of indoor residual spraying and such to reduce malaria carrying mosquitoes.

This is the best reference I can recommend to understand all of the details: http://apps.who.int/iris/bitstream/10665/69945/1/WHO_HTM_GMP...

Wow, then I was really lucky to have gotten dengue the last time I was in the country, 12 years ago. At the time I remember reading that there was little chance of it spreading back to the States where those mosquitoes don't exist, so I shouldn't be surprised that progress on a vaccine to cover all the strains remains slow. For better and for worse, Zika does not have that same challenge.

My partner is flying out to Sri Lanka on Friday for a 3 week solo tour around the country. Any places she should steer clear of? Any other tips you have would also be much appreciated.

My email is in my profile if you want to chat off thread.

> when DDT was banned in the 1960's

It's even more interesting that the link you provided explains that that's a complete myth. Read the whole thing.

My parents and grandparents lived through this period. I suspect what you're trying to say is that the DDT connection is a myth and not that you're discounting the collective memories of an entire nation?

Does anyone know what eradication techniques they used to such great effect on malaria, but allowed for an increase in dengue? I would've expected malaria and dengue to move together for any commonly used eradication technique.

Different mosquitos

>Success in controlling malaria over the past century has been attributed predominantly to widespread implementation of insecticide-treated bednets, household spraying of residual insecticides, and effective drugs to reduce mortality and interrupt transmission

doesn't work with Dengue because they bite during the day and there are no effective drugs.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3574272/

though there are other ways we might take out the aegypti blighters https://www.technologyreview.com/s/600689/we-have-the-techno...

https://news.ycombinator.com/item?id=11536074

Truly a monumental moment in human history, the beginning of the elimination of malaria, one of the biggest killers of all time

Next up, the flu.

Flu is practically impossible to eradicate at current technology levels because we don't have many defences against it and there is a large natural reservoir in wild birds.

Not really the beginning, but hopefully another big step. The USA was declared Malaria free in 1949 after a specific elimination project - it seems the CDC actually evolved from the Office of Malaria Control in War Areas, established in 1942.

[1] https://www.cdc.gov/malaria/about/history/elimination_us.htm...

And now there are more and more cases of Dengue and W. Nile and Yellow Fever in the US, mostly because the CDC stopped doing national mosquito control and its near powerless to resume that since NIMBY is more important than not catching tropical diseases apparently.

A much faster solution: https://en.wikipedia.org/wiki/Gene_drive

> Gene drives function only in secually reproducing species

I don't see why this is necessarily the case. Couldn't you, say, slow yeast budding to the point of population collapse?

Sure, causing your expensive crispr yeast to die out, while having no effect on wild yeast?

The only organisms affected in an asexually reproducing species would be the direct descendants of those that you treat. In a sexually reproducing species, the goal is to engineer the gene to spread throughout the entire population, even if it reduces the individual fitness.

Edit: though I guess I'm stating this poorly, since it would still only affect the direct descendants of those that you treat in a sexually reproducing species, however there's the possibility of that becoming 100% of the species without having to kill off all the untreated specimens.

As a person of Sri Lankan descent, this is great news. However, the elimination of malaria in Sardinia was correlated with the rapid rise of multiple sclerosis and type-1 diabetes. This is because the parasite that causes malaria is also thought to be protective against MS and diabetes [1]. I hope that was considered in this case, because if not we're just trading one problem for another.

[1]: https://bmcmedicine.biomedcentral.com/articles/10.1186/s1291...

Any ideas if this means the region is now also free of dengue fever causing virus that is also spread by mosquitoes?

I would guess not, because even Singapore and Bali are not dengue-free even though they are malaria-free. (But that's just a guess -- I'd be interested in a reliable source.)

I was there on a holiday a few weeks ago. While they told us that malaria isn't a problem anymore, they still warn tourists to protect against mosquito bites as they can still carry dengue fever. From a quick google it seems that malaria and dengue are spread by different mosquitoes, which might be why only one if the two is gone now.

Yep. Malaria is spread by Anopheles mosquitoes, while dengue, West Nile, yellow fever, and other Flaviviruses are mostly spread by Aedes mosquitoes.

In addition, Plasmodium (malaria) strains are much more species-specific than Flaviviruses. That is, while non-human animals can get a form of malaria, their malaria is usually not transmissible to humans. The Flaviviruses are much less selective (e.g., West Nile can infect birds as well as humans). This makes controlling the Flaviviral infections more difficult, as there's a virus reservoir in the animal population. Just wiping out the mosquitoes around humans isn't enough. You'd have to wipe out all the mosquitoes throughout the entire region.

Sri Lanka have had 38419 suspected cases of dengu so far this year: http://www.epid.gov.lk/web/index.php?option=com_content&view...

Compensation for Venezuela...

I dont get it.

Venezuela was the first country that was ever declared malaria-free, but is currently dealing with an epidemic due to various social and economic reasons. http://www.nytimes.com/2016/08/15/world/venezuela-malaria-mi...

Yes

Declared malaria-free by who?

(Sorry, couldn't resist...)

Seriously, this is very good news. But... does anyone know how hard it is to keep someplace malaria-free? Is this once-and-for-all, or does it require continual maintenance?

https://www.cdc.gov/malaria/about/history/elimination_us.htm...

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