CLOSE
iStock
iStock

Scientists Develop Quick, Inexpensive Paper Blood Type Test

iStock
iStock

Natural disasters and other emergencies often result in the need for blood transfusions. But they also can result in a loss of electricity, which can make it impossible to perform the tests required to determine a patient’s blood type. Now researchers in China may have an alternative: a cheap, rapid blood type test made of color-changing paper. They reported their progress in the journal Science Translational Medicine.

Each of the eight blood types has its own antigens and antibodies (either type A or type B), which help the immune system defend against unwelcome interlopers. Injecting a patient with incompatible antigens and antibodies causes the immune system to attack, making a person much sicker.

The researchers’ new blood type test works by identifying which antibodies and antigens trigger this immune attack. They mixed dye into two solutions, one containing antibody A and one containing antibody B, and printed small squares of the dye mixture onto either end of a long strip of paper.

Zhang et al. 2017. Science Translational Medicine.

 
To test a patient’s blood, they squeezed a few drops into the center reservoir. That blood then seeped through the paper, spreading toward the antigens at either end. Different blood types react differently to the antigens, causing the dye to turn either teal or brown. The entire process takes less than two minutes.

The researchers used both their new paper test and the current time- and electricity-intensive method to test 3550 different samples. The little piece of paper was astonishingly on-point, reaching the same conclusions as the electronic test 99.9 percent of the time.

More experiments are needed before the paper test will be ready for prime time, but it’s a very promising start. Along with recently developed paper microscopes and paper centrifuges, this cheap test could do a world of good in the places that need it the most.

[h/t Popular Science]

nextArticle.image_alt|e
iStock
arrow
Live Smarter
The Very Disgusting Reason You Should Always Wash New Clothes Before Wearing Them
iStock
iStock

It’s sometimes assumed that clothing with a price tag still dangling from the sleeve can skip an initial wash. Someone else may have tried it on, sure, but they didn’t run a marathon in it. Why not just throw it in the closet as soon as you get home?

One big reason: lice. As The Independent reports, Donald Belsito, a professor of dermatology at Columbia University Medical Center, told NBC's Today show recently that clothing fresh off store racks can harbor infestations of lice, scabies, or fungus.

You might be familiar with head lice as the dreaded insects that occupy the scalp and give school health monitors cause for concern. Head lice can be transmitted via clothing and other fabrics, and anyone who tried on a shirt or dress before you did can be a carrier. While they only live for one or two days without a blood meal, that’s still enough time to cause problems if something is being tried on frequently.

Scabies is far more insidious. The mites are too small to see, but the allergic reaction they cause by burrowing into your skin to lay eggs will be obvious.

Both scabies and lice can be treated with topical solutions, but it’s better to kill them by washing new clothes in hot water. A good soak can also get rid of formaldehyde, a common chemical used in fabrics to help ward off mold in case stock gets wet in transit. Formaldehyde can cause allergic skin reactions. For all of these reasons, it’s best to hit the washing machine before those new pants ever hit your hanger.

[h/t Independent]

nextArticle.image_alt|e
iStock
arrow
Health
How Promoting Handwashing Got One 19th Century Doctor Institutionalized
iStock
iStock

Regardless of how often we actually do it, it's common knowledge that washing our hands before eating, after coughing, and after using the bathroom is good for us. But the connection between handwashing and health wasn't always accepted as fact. As Danielle Bainbridge explains in the PBS web series Origin of Everything, the first doctor to campaign for cleanliness in hospitals was not only shunned by other medical professionals, but ended up in an insane asylum.

Prior to the 19th century, handwashing primarily existed in the context of religious ceremonies and practices. It plays a role in Christianity, Islam, Judaism, Sikhism, and Buddhism in some form or another. But washing up to stop the spread of disease wasn't really a thing for most of history. People weren't aware of germs, so instead of microbes, they blamed illness on everything from demons to bad air.

Then, in 1846, a Hungarian doctor named Ignaz Semmelweis made a breakthrough observation. He noticed that women giving birth with the help of midwives were less likely to die than those treated by doctors. He determined that because doctors were also performing autopsies on victims of puerperal fever (a bacterial infection also known as childbed fever), they were somehow spreading the disease to their other patients. Semmelweis started promoting handwashing and instrument sterilization in his clinic, and the spread of puerperal fever dropped as a result.

Despite the evidence to support his theory, his peers in the medical community weren't keen on the idea of blaming patient deaths on doctors. Partly due to his commitment to the controversial theory, Semmelweis was shunned from his field. He suffered a mental breakdown and ended up in a mental hospital, where he died a few weeks later.

Germ theory did eventually become more mainstream as the century progressed, and washing hands as a way to kill unseen pathogens started gaining popularity. Even so, it wasn't until the 1980s that the CDC released the first official guidelines instructing people on best handwashing practices.

If this story suddenly has you in the mood to practice good hygiene, here's the best way to wash your hands, according to experts.

[h/t Origin of Everything]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios