Its alright, we’re staph

The economics of vaccine discovery are, quite honestly, shit. We’re talking about a product that is only needed once or maybe a few times in a person’s life; the flu vaccine–which many can receive free or cheap–is the exception (at least currently – many are fiercely trying to develop a universal vaccine). So unlike once-a-day medicines for chronic diseases, the vaccine market is small and unattracive. And to top that off, the populations most in need are those least able to pay for the 15+ years of research and the expensive human testing necessary to receive government approval for use. Many of the traditional vaccines were initially developed for and tested on military members* (or members of society that were unable to protest, such as orphans or mentally ill. Yes, vaccines certainly have a dark side to them, like much of medical science. We can only strive to learn from mistakes) which bypassed the commercial benefits that modern pharmaceutical companies must weigh when deciding to pursue certain avenues of research.

All of that is a long way of saying: new vaccines are rare. Even rarer because many of the easy targets have been done–vaccine development requires a high level of creativity and understanding of disease progression. The researchers that developed an experimental staph vaccine display both of these qualities: a team at the University of Iowa this month propose a new approach to creating a staph vaccine that targets proteins produced by Streptococcus aureus’s that are highly involved in the disease caused by the bacterium instead of the traditional targets on the bacterium’s cell wall. The vaccine successfully protected rabbits–a controversial model for humans–and the researchers now hope to start human studies soon.

This is fascinating research because it shows the ingenuity of vaccine researchers to move beyond traditional techniques, but also demonstrates how difficult such development is, since there is no one-size-fits-all solution to creating a new vaccine. Unfortunately so many common infectious diseases have few current defenses we can employ, and few incentives for pharmaceutical companies to pursue the necessary research. Staph is a more attractive target than, say, dengue, because it does cause about 20,000 deaths each year in the U.S. alone. All of this is not meant to be a diatribe against the pharmaceutical companies; honestly, I sympathize and understand why they make the choices that they do. Vaccine research on diseases unlikely to provide a profit can only be pursued if the company expects to reap intangible, good-will profits from the paying populations (similar to companies that take advantage of consumers’ attraction to green business practices); but how does a company get credit for work on diseases that many have never heard of? Its a serious conundrum, especially as these diseases expand their endemic areas into developed countries.

*To see an incredible video of LSD testing on British military members, click here.

Advertisements

Project Tycho

Click to Enlarge Image
The history of weekly disease reporting in the United States since the start in 1888 until the present (2012). Each concentric circle represents a decade, starting with 1888 in the center. No single disease was reported at weekly intervals throughout the entire period, and for many diseases, the type of reports changed over time, as represented by different colors: red represents reports of deaths, and other colors represent reports of cases in different numbers of disease categories (e.g., hepatitis A and B) as follows: black, 1 category; green, 2; blue, 3; and orange, more than 3.
Source: Project Tycho website

The anti-vaccine crowd is going to have a hard time swallowing this one: a study published last week in the New England Journal of Medicine concluded that childhood vaccination programs since 1924 have prevented more than 100 million cases of serious contagious disease in the U.S. BOO-YAH.

Read more about the study through coverage in NYTimes here; unfortunately, I do not have access to the original study and I’m relying on reputable sources to report accurately. The study focused on seven diseases: polio, measles, rubella, mumps, hep A, diphtheria, and pertussis; seven diseases that we now rarely encounter in the U.S. because of these successful vaccine campaigns. The researchers came to the number of more than 100 million by projecting the number of cases that would have occurred had pre-vaccination patterns continued, factoring in population increases.

The incredible work of Project Tycho was integral to the study. Project Tycho digitalized the entire history of weekly Nationally Notifiable Disease Surveillance System reports for the U.S. (1888-2013), then standardized and cleaned the data format to create a database suitable for large-scale analysis. Anyone who has been part of any digitalization project can tell you, this is not easy work and much of the data must be entered or cleaned up painstakingly by hand (imagine the curvaceous scrawl of those 19th century doctors). The data is publicly available if you are curious about the spread of the 56 diseases included in the database. Its play time now!

For the original study: Panhuis, W.G., et al. Contagious Disease in the United States from 1888 to the Present. N Engl J Med 2013; 369: 2152-2158. 28 November 2013.

Social Networking

In the always-mysterious-but-wonderful ways of the world, the day after my last post on the effect of mass media on science understanding, Melanie Tannenbaum in a posting for Scientific American detailed part of her interview with author Brian Southwell on his new book Social Networks and Popular Understanding of Science and Health: Sharing Disparities. In her words, Southwell “explores the various reasons why there might be such huge differences in the extent to which health and science information gets ‘spread around’ in different populations.” Its a fascinating and engaging interview that I suggest y’all go check out!

Social Contagion

An interesting study by Frew, et al, at Emory University on factors that affect the likelihood of pregnant women to vaccinate themselves and later their infants against influenza also concluded, as a kind of sidebar, that the women participating in their study and saw the movie Contagion found the researcher’s messages about vaccination easier to remember and more appealing. Huh? Could a movie (which I have to admit I did not find all that wonderful) really have that much of an effect?

Malariotherapy

Science Magazine today highlighted a concept I frankly had never heard of:Malariotherapy. Between the early 20th century and the advent of penicillin in the 1940s, doctors would treat late-stage syphilis patients with one strain of malaria Plasmodium vivax, a “less deadly” version of malaria (that for other reasons can actually be more difficult to identify and control than the more common infection by Plasmodium falciparum – Science has details on that today too!). The high fevers that the malarial infection caused seemed to help the patient’s immune systems fight off the syphilis infection, and about half the patients recovered enough to resume normal activities (remember, this was late-stage syphilis – nasty nasty stuff! Malaria was kind of a last ditch effort; about 15% of those “treated” died from the malarial infection).

A quick search turns up relatively recent studies of malariotherapy to treat HIV and Lyme disease, suggesting the concept is not just a relic of the past. I’m personally a bit nervous using one nasty disease to try to treat another, but I’m would definitely be interested in exploring a theoretical discussion on the applicability of such therapies beyond just malaria (and why the original design of the syphilis treatment used malaria in the first place). Just some friday food for thought!

Tonight’s agenda: Watching Outbreak. Yes, I am an infectious disease nerd that has never seen the movie Outbreak. It’s embarrassing.

Red faces all around: South sudan polio free!

Other than surviving another round of tiny children dressed as ghouls, superheros, and maybe an ill-advised Honey Boo Boo, the World Health Organization had another reason to celebrate last Thursday: the polio outbreak in South Sudan, confirmed in August, was a mistake.

“There was a problem in the lab analysis,” WHO spokesman Oliver Rosenburg told NPR. “South Sudan is bing removed from the list of infected countries.”

YAY!

“but given that the Horn of Africa outbreak is continuing South Sudan remains at risk.”

Damn.

But wait, what about that sub-par lab analysis? “There was a specimen, which was sent from [South Sudan] for analysis in Nairobi [Kenya]. It got contaminated unintentionally with a specimen which was sent from Somalia. So the result was false,” explains Sudanese Health Minister Riek Gai Kok. Wait, the samples got contaminated, with each other? Excuse me?

I would like to think this was a one-time lapse in quality, but the realist in me fears this may be indicative  of a wider issue with proper laboratory procedure. I hope that at least this is sufficient ground for a detailed review of the poliovirus laboratory in Nairobi, which serves a critical function for several countries in the region to confirm or deny suspected polio cases.

World Polio Day is 24 October!

The first part of 2013 was a bumper crop of a year in the polio eradication effort: India in January marked two years without a single infection, the Polio Global Initiative in June published its Polio Eradication and Endgame Strategic Plan 2013-2018 that detailed a new plan to address what is needed to deliver a polio-free world by 2018; and the Taliban in May renounced its war on anti-polio workers (although attacks continue to occur).  And then news began trickling out about polio cases outside of the three endemic countries (Afghanistan, Nigeria, Pakistan), with Somalia the worst hit with 174 recorded cases of 296 worldwide to date (99 have been recorded in endemic countries). Somalia was removed from the list of endemic polio countries in 2001, and suffered only one previous outbreak. And then the news this week of a cluster of suspected polio cases in Syria where polio was last reported in 1999. Vaccination rates in Syria have dropped from an impressive 95% in 2010 to 45%, and the ongoing conflict will complicate response efforts; especially concerning to me is the high rate of displaced persons in Syria, which may lead to underreporting of cases.

Oy gevalt.

Celebrate World Polio Day on Thursday 24 October by watching the Smithsonian’s premier of a revised and updated version of the 2010 documentary “The Shot to Save the World” at 8pm. Clip below from Smithsonian Channel’s YouTube channel.

The HIV Vexation

An HIV vaccine for the last 30 years—ever since the HHS Secretary in 1984 suggested that a vaccine would be available within two years—has proved an elusive target, the research filled with much disappointment and false hopes. Recently, however, an experimental vaccine given to monkeys triggered a lasting immune response, and a 2009 trial in Thailand of the RV144 vaccine jointly developed by US military researchers and the Thai health ministry found a 31% protection rate; experts hope to start Phase II trial with a modified version of the vaccine soon.

But the bad news: unpublished analysis, presented on at the recent AIDS Vaccine 2013 conference in Barcelona, suggests that in two terminated trials of failed vaccines the risk of infection for participants increased. The first of these trials, called STEP, seemed to increase the risk of infection but then the risk narrowed when researchers included other factors such as circumcision and sexual activity. The second trial is not so clear: after shuttering the trial, the 800 participants were told if they had received the vaccine or placebo. When the research team followed up earlier this year, they found that overall the people who had received the vaccine were significantly more likely to be infected than those who had received the placebo even when accounting for biological and lifestyle differences in their participants. Outside biostatistical analysis of the data from two trials together found that the vaccine seemed to raise the risk of infection by 41%.  Some researchers question the results—people who receive a vaccine may have been more likely to engage in risky sexual behavior—but its still really unclear why the vaccine increased risk, and highlights the caution needed when conducting human trials: in the realm of scientific experiments, we’re a berserk variable.

But I still salute the researchers working hard on this important task: HIV is an epidemic that imposes an extraordinary and lasting burden on all aspects of society. The antics of the Government in recent years—sequesters, shut downs—has truly harmed the capabilities of U.S. science research, and I only hope that the drive and passion of our researchers can overcome such brinkmanship behavior.

To Do List: Buy Milk, Send Grandma a Postcard, Get a Flu Shot

Apologies for the sudden and long pause in this blog! After an unexpectedly busy August/September, I hope to return now to regularly updates.

Image Credit: New Yorker, 21 January 2013

 

Temperatures drop, the sun begins to favor the Southern Hemisphere, and we all begin to head indoors: thus begins influenza season. The flu virus has a fascinating ability to switch it up on us from year to year, usually through “antigenic drift,” or small mutations in HA or NA, two glycoproteins embedded within the viral envelope (these two glycoprogeins are where the “H” and the “N” in influenza types come from. Think H1N1, H5N1, H7N9 – the number refers to different HAs and NAs). This process occurs every two to three years. In contrast, an “antigenic shift” results from the reassortment of genomes among different flu virus strains, to include animal strains. Antigenic shifts occur infrequently but can be devastating, and is usually associated with the occurrence of pandemics – think H1N1. H1N1 was the result of a duck and a human strain of influenza co-infecting a pig—pigs being one of nature’s best mixing bowls—and the two strains reassorting to generate a new virus that infected our immunologically naïve human population.

Measles make you bumpy and mumps’ll make you lumpy

This has been floating around the internet mediasphere for a few days now, but it would be a flagrant error if I did not mention the recent measles outbreak in Texas. As of late today, 21 children and adults have been diagnosed with measles, which is a devastating event by itself considering the infamous MMR (measles, mumps, rubella – and the center of Andrew Wakefield’s vaccine-autism hypocrisy) vaccine can prevent infection (and is a requirement for Texas schoolchildren). All affected are affiliated with the Eagle Mountain International Church, whose senior pastor Terri Pearsons has allegedly expressed concern to her congregants over the link between autism and MMR vaccination; I tried to confirm this as several news organizations reference Pearson’s statements on the church’s website, but the news story has overwhelmed google’s search results and I can’t get to the church’s actual website. However, all 11 sickened children had not been vaccinated, according to the health department, and many of them were home-schooled or in the church-run daycare which avoids adhering to Texas’ requirements.

Pastor Pearsons now urges her congregants to take advantage of free vaccination clinics the church recently began offering, or to self-quarantine if they don’t want to receive vaccinations. Ugh: See can. Kick.

The US eliminated measles in 2000.*

This is the third major measles outbreak reported in the US this year.

 

Sources
Texas Church is Center of Measles Outbreak. The Wall Street Journal.
Measles Outbreak Traces to Vaccine-Refusing Megachurch. Forbes.

 

*eliminated means that there are no homegrown cases of the disease circulating within the borders; outbreaks occur when travelers–this time a visitor to the church who had recently returned from Asia–import the disease.