Wednesday, February 26, 2014

Let Me Out!

Earlier this month, commuters in the San Francisco area were warned that they may have been exposed to the highly contagious disease measles after a student at University of California, Berkeley attended class and rode the Bay Area Rapid Transit (BART) while contagious. The student, who was unvaccinated, likely contracted the disease while traveling abroad. Take a virus that can remain viable in the air of an enclosed space (like a classroom or subway car) or on surfaces for up to about two hours, a large student population of a university like UC Berkeley, and hundreds of thousands of commuters each day and you have a lot of people that were likely exposed to one of the most contagious viruses known to infect humans. Just look at BART alone, which sees roughly 390,000 riders each day. Of course, not all of those will ride in the same car as the student, but we can expect that at the very least, several hundred people would have been exposed to measles each time he rode. Cars hold about 60-70 people, the virus lingers for a couple hours, lots of people getting on and off during that period, it adds up. We could see additional cases popping up over the next week or two. And that's not the only case that California has seen. As of February 21, there have been 15 cases of measles, with the youngest being only 5 months old, according to a CDPH teleconference. Compare this to last year, when there were only 2 cases by the same date.

Those 15 cases make up the majority of the 24 cases seen nationwide to date, with other cases seen in Hawaii, Massachusetts, New York, Oregon, Pennsylvania, Texas, Washington and Wisconsin. The cases are in those who traveled to other countries where there are current measles outbreaks (e.g., the Philippines) or where measles is endemic (e.g., India) or among those who have had contact with someone bringing the virus back from another country. Since measles was eliminated from circulation in the U.S. in 2000, the outbreaks we have seen since then have been due to importation by unvaccinated individuals, some too young to be vaccinated, and others intentionally unvaccinated. Note that none of the outbreaks in recent years has been started by a fully immunized individual. With the risk posed by importation of the disease, I started to think about what role quarantine might play in mitigating potential harm to the public.

Saturday, February 15, 2014

Forging Potential Harm

In the United States, every school maintains records on the immunization status of its students. Which students are fully vaccinated? Which have medical exemptions? Who get a religious or philosophical exemption for one or more vaccines? In the event of an outbreak of a vaccine preventable disease, these records can be used by the school to figure out which students are at risk and should be kept home until the outbreak is over. Public health officials also benefit from these records, as they can report vaccination rates across the state. This can show which communities may be vulnerable to a disease outbreak and narrow down where investigators need to look for potential index cases or contacts during an outbreak.

I've written before about an instance where parents forged their children's immunization records so they could get into day care. In that instance, the unimmunized children developed chicken pox, creating a small outbreak of the disease that put the other children, as well as two pregnant staff members, at risk of infection. This raised the question of the legal liability to the parents for their actions, handily addressed by The Skeptical Lawyer. No charges were filed in that case, and it's unlikely that any legal actions would have prevailed, according to the Skeptical Lawyer. A couple months after my original post, there was a chicken pox outbreak at a day care center in Alaska's Kenai Peninsula. Just like the earlier case, the parents refused vaccination for their children, ultimately resulting in a small outbreak.

The issues raised by those two events came together recently, again in Alaska's Kenai Peninsula. A nurse at a public school forged parent signatures on four immunization documents, noting in one instance vaccine refusal for religious reasons.

Tuesday, February 11, 2014

Weaving Ethical Dilemmas

Imagine, for a moment, that a device existed that could recreate just about any experience a person could have. Not like a television, video game or movie. Not even like a virtual reality simulator. Instead, it interfaces directly with the brain, stimulating specific regions to fire so that the user is, at least temporarily, completely convinced that they experienced whatever event was played. Every sight, sound, smell, taste and touch, even the very emotions evoked, all created by the device in the user's brain. Want to climb Mt. Everest from the comfort of your own home? Just run the right program and when it's done, you'll feel like you have. Want to sit on a tropical beach, lounging with a cool drink in your hand and just admire the majestic ocean, waves rolling in to murmur on the sandy shore? Run a different program, feeling completely relaxed when it's over.

That's the premise of a novella I just finished reading, called The Dream Weaver, by Aaron Simmons, who wrote the story as part of the annual National Novel Writing Month (aka NaNoWriMo). The central character is Eric Bram, a fellow who kicked off the technology and producer of some of the best "weaves" on the market. Bram, however, is wracked with guilt as he learns about the growing issue of addiction associated with the Dream Weaver device, wondering what role he may have played in the spread of the problem. Simmons weaves (excuse the pun) an intriguing tale that hints at far more considerations than could fit in the brief tale. So, I thought I'd explore some of the things that came to mind as I read it. Feel free to add your own thoughts in the comments. If you don't want the book spoiled, I suggest giving it a read before continuing on below.

Thursday, February 6, 2014

Mississippi Parent Group Working to Make It Easier to Get Sick

In the United States, every state has some manner of requirements for immunizations before children are allowed to attend schools or day care. They vary from state to state, with some requiring almost all of the vaccinations on the recommended immunization schedule, while others only require a smaller subset. Each state decides which ones they will require, and which they simply recommend. As with any medical intervention, there may be medical reasons that a person should not receive a vaccine. Usually, this is something like an allergic reaction to a previous immunization or one of the ingredients or because at the time the shot would normally have been given, the patient had an illness which contraindicated the vaccine. In other instances, the child may have a chronic disease or disorder that prevents safe immunization. Because of this, every state allows for medical exemptions to school immunization requirements. Nearly all states allow for a religious exemption, with Mississippi and West Virginia being the odd ones out. A smaller proportion of states allow for a broader sort of exemption: the philosophical (or personal belief) exemption. Like the laws requiring immunization, these exemptions vary by state (a map of which states allow which type of exemptions can be found at the Institute for Vaccine Safety).

As I mentioned, Mississippi and West Virginia are unlike the rest of the country, in that they only allow for medical exemptions from school and day care immunization requirements. However, a recent report in the Clarion Ledger discusses the efforts of one organization to change the law in Mississippi, by trying to pass legislation that would establish a philosophical exemption in that state.