
Cheap Smartphone Dongle Diagnoses HIV And Syphilis - joewee
http://www.iflscience.com/health-and-medicine/cheap-smartphone-dongle-diagnoses-hiv-and-syphilis-15-minutes
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shutupalready
Was it really necessary to involve a smartphone at all?

> _color change [is] picked up by a set of photocells in the dongle, and the
> results are then sent to an app_

The logic to discriminate a color change could have been handled by a 75-cent
microcontroller. Add a cheap display or a couple LEDs to show the test result,
plus a cheap AA battery, and you have a self-contained gadget for less cost
than creating the smartphone interface.

Pregnancy tests and all sorts of sophisticated chemical test strips don't
involve a smartphone.

I'm thinking that the smartphone hookup is either:

(1) a way to add future functionality like maintaining a database of the tests
or uploading test results to somewhere (with all the privacy implications and
risks of those), or

(2) a marketing ruse since we all know that a smartphone app that does X is
way cooler than a old-fashioned self-contained gadget that does X.

An an example of how easily people fall for coolness of having a smartphone do
something that doesn't actually need a smartphone, check out this comment to
the original article:

" _I have been resisting the smartphone trend for years because they are
expensive and there was no unique use for them: everything a smartphone did I
ALREADY own a gadget for. This changes the game. Now I want a smartphone._ "

~~~
Fomite
A couple thoughts:

1\. The comment you're talking about is from, essentially, someone who doesn't
know what they're talking about. This isn't really meaningfully a "game
changer" in terms of "Should I buy an iPhone?"

2\. Computers are already used to analyze many of these types of diagnostic
tests. It may have been easier to port _those_ systems to a smart phone than
to develop a new, bespoke microcontroller. Expertise is a cost.

3\. There are _massive_ benefits to having this hooked up to a smart phone,
and as you have mentioned, much of it goes to extra functionality. During the
Ebola outbreak, case reports often had to be dealt with in paper forms
processed by hand, which slowed both reporting and contact tracing. From a
public health perspective, being able to link test results (deidentified or
not) with a central repository at a ministry of health is a big deal.

Imagine the use case of this not as one person and a smart phone testing
themselves. Imagine it as one person and a smart phone testing 4 villages over
the course of the week, in conjunction with actually getting people treatment.

~~~
shutupalready
> _1\. The comment you 're talking about is from, essentially, someone who
> doesn't know what they're talking about._

Yes, of course, the person who made that comment is clueless about technology
-- just like 90% of the population. The comment shows that most people think
it's really cool that the diagnostic device uses a smartphone and don't
realize that the smartphone wasn't needed at all.

> _2\. ... than to develop a new, bespoke microcontroller._

Nobody needs to develop a new, bespoke microcontroller. You use a tiny cheap
off-the-shelf microcontroller (like the PIC) and _program_ it. Based on the
information available in the original article, the program might be as simple
as light the red LED (positive) if the color sensor indicates it's above a
certain threshold and light the green LED (negative) if below a certain
threshold. But even very complex algorithms can be ported to microcontrollers.

> _3\. Imagine it as one person and a smart phone testing 4 villages_

I did say databases and uploading were a possible reason for the smartphone,
and do I agree that a smart phone does make sense for the use case of testing
a whole village. This doesn't change my original point that a smartphone
wasn't really necessary, not even to reduce costs, and might in fact be more
expensive than a standalone device. The original article makes a big deal of
the smartphone connection without explaining the real reason why the
smartphone is there.

------
smoyer
That reminds me of a parody of the lean start-up movement - a must-read in my
opinion:

[http://theanorexicstartup.com/wp-content/the-anorexic-
startu...](http://theanorexicstartup.com/wp-content/the-anorexic-startup.pdf)

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carlosgg
They were featured on the Science Friday podcast:

[http://www.sciencefriday.com/segment/02/06/2015/honey-i-
shru...](http://www.sciencefriday.com/segment/02/06/2015/honey-i-shrunk-the-
lab-testing-for-stds-on-a-smartphone.html)

------
DanBC
This pages talks about the false positive rate of some existing tests:

[http://mobile.aidsmap.com/Accuracy/page/1323395](http://mobile.aidsmap.com/Accuracy/page/1323395)

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seesomesense
False positive rate : 14% LOL !

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swamp40
No dongle jokes, please...

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chris_va
1) To be pedantic, it detects your immune response (not the microorganisms
directly)

2) "14% false alarm rate" => That makes it basically useless.

~~~
stormbrew
False negatives are very bad. False positives not so much. Worst case is you
send someone to a better test to find out if it's true. This is what they aim
for with home pregnancy test kits, afaik, for pretty good reasons.

~~~
Fomite
That very much depends on the disease in question. For _these_ diseases, false
negatives are bad. For diseases with intensive and dangerous treatments, false
positives can be actively harmful to population health. This is commonly a
problem in cancer screening.

~~~
cdcarter
Disease and plan. Almost every rapid HIV test out there is spoken about in
"negative" or "maybe positive" terminology. If you get the two dots instead of
one dot, you're referred to a physician who will administer a 4th gen test and
probably a western bot, you aren't immediately started on ARVs.

------
SwellJoe
So, assuming the medical industry in the developed world gets out of the way
(which I don't think is a foregone conclusion...it will take years, and
possibly too many resources, to bring this to market in the US for a variety
of good and bad reasons related to our regulatory environment), this is
potentially one of the biggest revolutionary changes in healthcare in my
lifetime.

This makes detection of both viral and bacterial infections possible with very
low-cost tools; the fact that it can detect both makes me believe that
detecting practically any infectious disease (or at least any infectious
disease that has identified biomarkers in blood, or other easily obtainable
bodily fluid) is on the near horizon.

One could buy this dongle, or one like it, and new diseases could be added via
software upgrades (or by in-app purchases for the diseases you want to check
for). This would potentially make doctors office visits obsolete for all but
serious disease and chronic conditions. No need to go get checked for strep
when you have a sore throat (of course, getting the antibiotics to treat it is
another regulatory hurdle people in the US would face), lower need for cities
and universities to provide STD testing, though treatment and education would
still likely be within their perview. It allows better self-management of HIV,
hepatitis, Lyme disease, and other chronic viral illnesses through more rapid
and frequent testing.

Even if this doesn't evolve to include other types of detection, I would still
happily pay several hundred dollars for a re-usable STD testing tool. I like
to get tested every 6 months, but the hassle and cost of going to the doctor
or Planned Parenthood or online testing lab is high (free or low cost testing
is available, but you trade much more hassle for the lower cost...among my
friends who get tested at the city health center, they usually spend an hour
or two waiting, which is not a cost I'm willing to pay to save a couple
hundred bucks). If I could test for HIV for free before every new partner
(and, hell, make it a practice to test with every partner), that'd be
fantastic.

Another article about this was posted a week or so ago to HN, but it didn't
get any comments or many upvotes, which was disappointing, as this seems like
entirely revolutionary technology, to me. And, it makes me want to go into
medical tech because of how huge the potential is (but it would be an entirely
new field for me, so my ability to be productive in it would take a while to
develop).

~~~
XorNot
You cannot _possibly_ software update a device like this. The actual detection
mechanics are chemical. The advance is in miniaturizing and automating tasks
which used to take a laboratory and staff to do.

~~~
SwellJoe
Is it? I don't know the mechanics. How about genetic testing, is that also a
chemical process that is unique for each marker? Seems like a genetic
sequencing tool could be programmable once the DNA/RNA has been analyzed. The
best HIV test available is an RNA test, which can provide results as early as
six days after exposure. This is obviously not my area of expertise, so I
don't know how realistic it would be to downsize such a thing.

Also, how does this device perform a test for a viral infection and for a
bacterial infection, if the tests are unique and chemical? Does it use a
particular substance for each test, which has to be refilled per use? (Again,
I have no idea how this stuff works.)

I know that 23andme continues to produce new information about my genes as new
studies are done to find genetic markers for various diseases and traits,
which is pretty cool. If there were a device that detected viral and bacterial
RNA/DNA, would that be software extensible?

~~~
Fomite
Yes, the tests are unique and chemical. You either need bespoke antigens that
will react to the presence of specific pathogens, or primers and other
components for DNA/RNA based tests.

Beyond that, these testing systems probably can't manage the sensitivity and
specificity of a properly run diagnostic lab. That's _fine_ for the setting
they're being considered in, because those labs don't exist, are hard to reach
or can be easily overwhelmed in an outbreak, but for a developed world
setting? I don't really see it. Home diagnostics for infectious diseases over
a broad range of potential pathogens is a really hard technical challenge with
no real payoff - you still need to go to the doctor.

~~~
bitCromwell
If you have accurate test results that show you need medicine and can obtain
it without a gatekeeper then you don't "need" to go to a doctor. That's one
hell of a payoff.

~~~
Fomite
Yeah, there's no way you're getting prescription antibiotics or antivirals
without seeing a doctor because "My iPhone says I have pertussis".

Lab results alone do not a medically responsible treatment plan make.

~~~
bitCromwell
Its unclear who "you" means, most people on earth can actually buy antibiotics
without this. Also unsure as to how you define what is "responsible" for them.

~~~
Fomite
The post at the top of this chain makes it abundantly clear we're talking
about the United States.

And, as an epidemiologist, the ready availability of antibiotics without any
interaction with a doctor is something I'd be pretty comfortable classifying
as inherently irresponsible.

