VOA标准英语2013--iPhone Becomes Low Cost Microscope

iPhone Becomes Low Cost Microscope

The Apple iPhone can be used for lot of things – making calls, playing games and sending pictures, video and text. Scientists say it also can be converted into a low-cost microscope to detect worm-related infections in children.

Dr. Issac Bogoch, an infectious disease specialist at Toronto General Hospital, says with a few dollars and a little ingenuity 1, the "smart phone" is turning into an important medical diagnostic tool in places that often lack such techology, like rural Africa. 

“I used an iPhone 4s and that’s simply because I just happen to own one, but any smart phone with a decent camera and a zoom-in function should work just fine," he said. "Then we bought a ball lens, which is about eight dollars. We just got it online. And then we used some double-sided tape to stick the ball lens to the lens of the camera on the iPhone.”

Bogoch is the lead author of a new study on the iPhone-turned-microscope. It appears in the American Journal of Tropical Medicine and Hygiene 2.

“We got this idea from reading some of the medical literature, and we saw that some other groups had published neat images that were taken in the laboratory using smart phones and converting them into microscopes," he said. "But we thought that this was a really neat concept and we wanted to take it to real world and practical settings."

Bogoch and his colleagues from Massachusetts General Hospital and the Swiss Tropical and Public Health Institute tested their idea on Pemba Island in Tanzania.

“We were looking at school age children that are unfortunately disproportionately affected 3 by intestinal 4 parasitic 5 infections. And these infections affect over a billion people on the planet,” he said.

The make-shift microscope could detect parasitic infections to varying degrees. The best results came in detecting moderate to heavy infections. Results were not as good for mild infections. However, Bogoch thinks that will change when the technology improves.

“We took slides. We were looking for intestinal parasites 6. So these are stool samples. The slide had a little bit of cellophane covering the stool sample and we put the slide very close to our ball lens, which was stuck up against the iPhone. And we were able to zoom-in and we could see the parasites that we were looking for pretty easily.”

Intestinal worms include hookworms and round worms. They can cause chronic 7 anemia 8 and malnutrition 9. Typical diagnosis 10 is done by examining a stool sample with a conventional light microscope.

Bogoch said that the next step is to improve the image quality. He says the smartphone microscope could greatly enhance disease control in poor, rural areas. He added that treatment for many intestinal parasites is generally widely available and very well tolerated.

If health workers in the field are unsure what the image means, he says they could text or email it to experts elsewhere and get a diagnosis a short time later.