Tuesday, March 28, 2017

A New Vaccine Against a Diarrhea-Causing Virus

A new vaccine may represent an improvement over older vaccines against a deadly virus that causes severe diarrhea in children. The virus, called rotavirus, kills over 200,000 children under the age of five each year, mostly in Pakistan, India, and the African continent.

Current rotavirus vaccines have two drawbacks; they are only partially effective, and they require refrigeration. The need for refrigerated transport and storage of a vaccine or medicine is a real problem in very poor and very rural environments, where infrastructure is inadequate and even the availability of electricity may be sporadic. The new vaccine, called Rotasiil, is manufactured by an Indian company and was tested in Niger, where it proved to be 67% effective; as good or better other vaccines currently available. It does not need to be refrigerated, it can be delivered orally, and as an added bonus it's expected to be inexpensive, or at least cheaper than other available vaccines.

Over 200,000 childhood deaths a year, and you've probably never even heard of rotavirus! In the U.S., rotavirus infection is rare because vaccination against rotavirus is just part of the normal childhood vaccination schedule; its given as either one or two doses before the age of six months. Just goes to show that there are a lot of pretty nasty bugs out there, and not everyone in the world is equally protected against them.

Friday, March 24, 2017

Using Cellphone Photos for Medical Analyses

There's an app now for taking medical-grade selfies of a sort. Actually, they're selfies of urine dipsticks, useful for diagnosing and monitoring certain diseases and conditions.

Clinical diagnosis of certain diseases and conditions relies on simple dipstick analysis of a sample of urine. Typically, a paper dipstick that changes color when dipped in urine is compared to a color chart to determine the presence or absence of certain substances in the urine, such as glucose, blood, or protein. Diagnosis depends on a physical comparison of the color of the dipstick to a reference color chart.

It would be nice to be able to just take a photo of the dipstick and send it in to a health professional, so that diagnosis could be done remotely without the patient having to go to a clinic. But the problem with photo analysis of a dipstick is that the colors depend critically on lighting conditions and the angle at which the photo is taken. But now an app developed by an Israeli company called Healthy.io has gotten around that problem. First, a photo of the dipstick is taken against a proprietary color card. The app, called Dip.io, then color-corrects the background colors to mimic natural ambient light and reads the dipstick. The company hopes that Dip.io will provide patients and their physicians with an easy and inexpensive way to monitor certain diseases characterized by substances in the urine, such as diabetes (glucose), chronic renal failure and pre-eclampsia of pregnancy (protein), and urinary tract infections (blood).

The ability to standardize photographs for color and size opens up all kinds of possibilities. Take dermatological conditions, for example. If moles on the skin were photographed against a background card displaying objects of various sizes and colors, the results could again be standardized to allow long-distance diagnosis. The barriers to entry into this exciting new development in distance medicine are low (just the development of an app), so we can expect Healthy.io to have healthy competition in the future.

Disclosure: I have no financial interest in Healthy.io, nor do I expect to have one in the future. I'm just interested in new and interesting medical technologies.

Monday, March 13, 2017

Congress May Curtail GINA's Protection of Your Genetic Information

A law passed in 2008 called the Genetic Information Nondiscrimination Act (GINA) prohibits employers and health insurers from requiring you to submit to genetic testing as a condition of employment or to receive health insurance (see this blog, June 2, 2008).  It also prevents employers or health insurers from requiring you to answer questions about any previous DNA tests you may have had.  GINA was designed to prevent discrimination based on genetic information about your future health risks.  (Interestingly, GINA does not apply to life, disability, or long-term care insurance; see this blog, Apr. 17, 2014).

Now a bill introduced in the republication-controlled Congress is attempting to take away the protections written into GINA.  H.R. 1313 would allow employers to ask employees intrusive questions about the employee's health, as well as about the health and any genetic tests they or their family members have undergone in the past.  Although refusing to answer still can't be used against the employee in terms of employment, those who choose not to answer could be required to pay 30-50% more for their company-provided health insurance.  In effect, H.R. 1313 would require employees to choose between privacy of their genetic information and the cost of their health insurance.

By the way, the definition of "family member" used originally in GINA and adopted by H.R. 1313 goes way beyond just parents or children.  It extends to the fourth degree, meaning from great-great-grandparents to great-great-grandchildren, as well as generations of aunts, uncles, and cousins.  H.R. 1313 could potentially expose your extended family's entire genetic history, to the extent that it is known.

I'd be wary of agreeing to any genetic tests if this bill passes. You can't answer what you don't know.

Friday, March 10, 2017

Colorectal Cancer is Increasing in Young Adults

Colorectal cancer is generally considered to be a cancer of older people - so much so that the current recommendation is for colorectal cancer screening (a colonoscopy) every ten years after the age of 50. Most cases of colorectal cancer occur in people over 6O. Overall, the incidence of colorectal cancer has started to decline. However, in recent years there has been a sharp rise in colorectal cancer in the young. According to a report published in the Journal of the National Cancer Institute, adults born around 1990 (now in their 20s) have twice the risk of colon cancer and four times the risk of rectal cancer as a person who was born around 1950 when they were in their 20s.

The reason for this startling increase in risk for young people is not known. To be fair, the actual risk of colorectal cancer for persons in their 20s is still very low; about 1 case/yr. (per 100,000 population), compared to the over 50 cases/yr for persons over 60.  If you're young, it's probably not worth worrying about.

However, the trend toward an increase in risk for the young is of concern to scientists, if only because we don't understand why it is happening when overall risk across all age groups is declining.  It's worth keeping an eye on.  At the very least, physicians should not rule out the possibility of colorectal cancer in their younger patients.  Perhaps persons who have a family history of colorectal cancer should consider being screened before age 50.

Tuesday, March 7, 2017

Bird Flu is On the Rise Again

A deadly type of bird flu known to be transmissible to humans, called H7N9, seems to be breaking out again this flu season in China. H7N9 has caused only modest outbreaks since 2013, the year it was first identified (see this blog, Apr. 17, 2013). The intensity of yearly H7N9 outbreaks peaked in 2014 and then seemed to decline in 2015 and 2016, leading some health officials to think that the worst was over. Not so, it seems. The current 2017 outbreak of H7N9 (which began in October, the typical start of the winter flu season) is the worst outbreak yet. According to the World Health Association (WHO), more than a third of all cases of H7N9 flu ever recorded have occurred during this year's outbreak, and flu season isn't over.

H7N9 bird flu is not easily transmitted from birds to humans, but it is quite virulent. The death rate from confirmed H7N9 infections in humans is nearly 40%. So far, there are no confirmed cases of human-to-human transmission. Health officials worry that if/when the virus mutates in a way that makes it easily transmissible between humans, we could face a worldwide pandemic.

For now, H7N9 outbreaks have been confined to China, where close contact with poultry is much more common than it is in this country. Are we prepared for a H7N9 bird flu pandemic? The short answer is "no". At the moment there is no vaccine against it. Let's hope that a change to human-to-human transmission of H7N9 doesn't develop anytime soon.

Thursday, March 2, 2017

Supreme Court Nominee Gorsuch Opposes Death With Dignity Laws

Judge Neil Gorsuch, president Trump's nominee to the U.S. Supreme Court, is not a supporter of death with dignity (also called medical aid in dying) laws. In his 2009 book entitled The Future of Assisted Suicide and Euthanasia he defends his position, writing "...all human beings are intrinsically valuable and the intentional taking of human life by private persons is always wrong."

Five states (Oregon, Washington, Vermont, Colorado, and California) currently have death with dignity laws, and several others are considering them. In general these laws allow a person to terminate his/her own life under certain very narrow circumstances, which generally include the presence of a terminal illness, adequate counseling, and the consent of a physician. The Supreme Court has not yet considered a case involving these laws, so for now the states can make their own decisions.

Not every state is likely to pass death with dignity laws; indeed, some state's legislatures or legal counsels actively oppose them. The deputy solicitor general of the state of Wisconsin, for one, is already thinking about strategies for opposing death with dignity laws, should one ever be challenged in the federal courts.

The first challenge to a death with dignity law in the Supreme Court is likely to have a friend in Justice Gorsuch, should he be confirmed by the U.S. Senate. Just sayin'.