Various viruses
tsmith | December 29, 2008As the Philippines requests international assistance to investigate the finding of Ebola Reston in their pigs, another human outbreak of Ebola has been confirmed in the Democratic Republic of Congo:
The Ministry of Health (MoH) of the Democratic Republic of the Congo declared on 25 December an outbreak of Ebola haemorrhagic fever in Mweka District, Kasai Occidental province based on laboratory results from the Centre International de Recherches Médicales de Franceville (CIRMF) in Gabon. CIRMF confirmed the presence of Ebola virus in 2 samples from 2 of the patients in the outbreak by antigen…
tsmith | December 11, 2008 I've mentioned repeatedly how little we know about Ebola ecology--what the reservoir host(s) are, how it's transmitted to humans (and other species), why it causes outbreaks when it does. We know even less about the Reston subtype of Ebola, which--in contrast to the Zaire, Sudan, Ivory Coast, and Bundibugyo subtypes, originated in Asia and was first found in monkeys imported into the United States for research purposes. It also is different from the other subtypes in that it appears to be only mildly lethal to monkeys, and several asymptomatic human infections have been documented (but…
tsmith | December 5, 2008A pair of positive stories in the news today. The first involves guinea worm, a nasty parasitic disease. The worms have a complex life cycle, but contaminated water plays a key role. Worm larvae within the water are hosted by a water flea, which may be ingested by humans. In the stomach, the water flea will be digested, but the hardy larvae will travel throughout the body and eventually emerge from the body through the skin--usually in the lower extremities. This causes a very painful burning sensation, which the victim may try to relieve with water--allowing the female worm to…
tsmith | November 20, 2008 Few things can take me out of blogging hibernation (especially when the next grant deadline is Monday...) However, one of those things that I'll carve out time to write about is an interesting, hot-off-the-presses Ebola paper, and especially one describing a new strain of the virus--and there just happens to be such a paper in the new edition of PLoS Pathogens. Details after the jump...
Previously, 4 types of Ebola viruses had been identified. Ebola Zaire has typically been the worst as far as fatality rates (around 80-90%), with Ebola Sudan coming in close behind (roughly 50-70%). The…
tsmith | September 4, 2008 Oh, let's go back to the start... --Coldplay, "The Scientist"
A decade ago, a paper by Andrew Wakefield and colleagues was published in The Lancet, detailing the cases of 12 children with autism spectrum disorder (ASD). Anecdotal reports from parents of several of these children suggested that the onset of their condition followed receipt of the measles, mumps, and rubella (MMR) vaccine. Wakefield concluded following this research that the MMR vaccine was unsafe, and could play a causative role in the development of autism as well as gastrointestinal disease--the first volley in the…
tsmith | July 11, 2008Marburg is a filovirus; a cousin of Ebola. Both cause hemorrhagic fever; both have been recently discovered in fruit bats; both have hit Africa in a small number of human outbreaks. Both also remain largely mysterious; we know very little about their ecology in the wild; how frequently they really infect humans (and other animal species; Ebola especially has taken a toll on great apes); and their mode of transmission from their wild reservoir to primate hosts. These enormous gaps in our knowledge remain despite recently passing the 40-year mark since the discovery of filoviruses in a lab…
tsmith | June 25, 2008I had ended up with a ratty old piece of Army gear, a space suit that belonged to nobody A little voice started speaking in my head. What are you doing here? the voice said. You're in an Ebola lab in a fucking defective space suit. I started to feel giddy. It was an intoxicating rush of fear, a sensation that all I needed to do was relax and let the fear take hold, and I could drift away on waves of panic, screaming for help.
Martha was looking into my eyes again.
The little voice went on: You're headed for the Slammer.
Richard Preston opens his new publication, a collection of essays…
tsmith | May 15, 2008I'm taking a quick hiatus from my hiatus. I mentioned that I had quite a bit of travel upcoming, and I happen to be in the midst of my first trip. However, it just so happens that where I've landed--Ulaanbaatar, Mongolia--is experiencing an outbreak of hand, foot, and mouth disease in kids, caused by Enterovirus-71. More after the jump...
You may have read about this virus in prior weeks, as China has been dealing with a major outbreak there:
The number of hand-foot-mouth disease (HFMD) cases reported in China this year rocketed to 15,799 as of Tuesday, resulting in 26 deaths, according…
tsmith | April 16, 2008This is the fifth of 6 guest posts on infection and chronic disease.
By Whitney Baker
My previous blog post examined the idea of an infectious etiology for obesity by a group of possible infectious agents. While these pathogens have been associated with obesity in humans or animals, their causative role in human obesity has not yet been established. So for this round, I thought I'd focus in on the bug showing the most evidence for human obesity: Adenovirus-36.
(More after the jump...)
First, a little background on Adenovirus [1]... it most commonly elicits respiratory illness; however…
tsmith | April 14, 2008This is the first of 6 guest posts on infectious causes of chronic disease.
By David Massaquoi
Is this the Beginning of the end of antibiotic resistant problem or just another scientific false hope of eradicating microorganisms that have co-existed with humans for millions of years? In the days before antibiotics, some researchers saw bacteriophages, viruses that can seek out and destroy bacteria, as a promising candidate for fighting infections. Now, as more organisms develop resistance to existing antibiotics, phage research is finding new favor.
(More after the jump...)
At the Society…
tsmith | April 10, 2008 It's hard to believe that it's been 2 years since Iowa's 2006 mumps outbreak (more background and details on that here, here, here, and here).
By the time the outbreak ended, 8 states had been heavily affected (and 45 reported at least one case), with a total of 6584 cases of mumps and 85 hospitalizations reported by the end of 2006. All told, this was the largest outbreak of the virus in approximately 20 years, after a 1986-1990 outbreak resulted in a change in the recommended vaccine schedule (adding a booster shot of MMR).
A paper out in today's New England Journal analyzes the…
tsmith | March 25, 20081980 marked a milestone in infectious disease epidemiology: the World Health Organization declared the smallpox virus eradicated in the wild. However, while smallpox currently exists only in frozen stocks, poxviruses as a class certainly haven't disappeared. A related virus, monkeypox, regularly causes illness in Africa, and even spread half a world away in the American midwest.
Additionally, Africa isn't the only area with endemic poxvirus infections. Brazil has been dealing with their own poxvirus outbreak, and poxviruses have popped up in Europe as well. More on both of those after…
tsmith | March 7, 2008It's just not been Vegas' week. First a ricin-laced hotel room, then a clinic-associated outbreak of hepatitis C virus (and potentially hepatitis B and HIV) that could become enormous. Meanwhile, an outbreak of hepatitis E is raging in Uganda. So what are these virues, and how in the world could a medical catastrophe of this magnitude happen in the U.S.? More after the jump...
The group of hepatitis viruses (A, B, C, D, E, and G) are related in name only. They've all been either associated with or found to cause hepatitis--inflammation of the liver. This can be acute inflammation (short…
tsmith | February 27, 2008This is the sixth of 6 guest posts on infectious causes of chronic disease.
By Ousmane Diallo
I was dumbfounded when I read this news article relating HPV to the increase of lip and oral cancers because of oral sex.
It reminded me my younger years, as a med student, debating with my professor of psychology the fundamentals of Freudian psychoanalysis, the Id, the Ego and the Super-ego. It was a rather philosophical debate more than anything else, a combination of religious and cultural reciprocal statements of beliefs. At that time, we were exposed to the new French "sexual education"…
tsmith | February 26, 2008This is the third of 6 guest posts on infectious causes of chronic disease.
By Whitney Baker
While working out at the gym last night, I was perusing the latest SHAPE magazine to help pass the time. In it, I read a small article about researchers finding an association between Adenovirus-36 and human obesity. Since I am in the infectious disease field, I was already aware of this proposed link- an infectious cause (or contributor) for obesity. But for the millions of health-conscious readers hearing of this for the first time, what would they make of it? Would they have visions of…
tsmith | February 25, 2008This is the first of 6 guest posts on infectious causes of chronic disease.
by Matthew Fitzgerald
Viruses cause cancer?
Cancer researchers have for decades known that viruses can cause cancer. It is now estimated that 15% of the world's cancers are caused by infectious diseases including viruses. Some of these include: Human Papilloma Virus (HPV) and cervical cancer; Epstein-Barr Virus (EBV) and nasopharyngeal cancer & lymphoma; Hepatitis B and liver cancer. In fact cancer researchers use this knowledge of viruses causing cancer by utilizing EBV and SV40 and other viruses to "…
tsmith | February 8, 2008The fever hit suddenly in the form of a piercing headache and painful sensitivity to light, like looking into a white sun. At that point, the patient could still hope that it was not yellow fever, maybe just a headache from the heat. But the pain worsened, crippling movement and burning the skin. The fever rose to 104, maybe 105 degrees, and bones felt as though they had been cracked. The kidneys stopped functioning, poisoning the body. Abdominal cramps began in the final days of illness as the patient vomited black blood brought on by internal hemorrhaging. The victim became a palate…
tsmith | January 25, 2008 A few months back, I blogged about World Rabies Day, noting that this virus is still a huge public health threat in many areas of the world. A few weeks ago, biologist Olivia Judson wrote a post on a potential "coffin for rabies" on her New York Times blog, describing more about the reality of the disease and what we could do to practically wipe out this virus in humans. I have a bit more on it over at Correlations.
Image from http://www.powhatananimalhospital.com/disease/rabid%20dog.jpg
tsmith | December 30, 2007 As another Ebola outbreak simmers in Uganda (and appears to be increasing), I recently was in touch with Zoe Young, a water and sanitation expert with Médecins Sans Frontières (MSF*, known in the US as Doctors without Borders), who was working in the Democratic Republic of Congo during the DRC Ebola outbreak earlier this fall (and blogging it!)
Regular readers know of my interest in this virus, but I'm obviously geographically removed from any of the outbreaks. As such, Zoe and her colleague, physician Armand Sprecher, were generous enough to answer my questions about their work with…
tsmith | December 21, 2007 It's been awhile since I wrote anything on influenza. It's certainly not that nothing interesting has happened recently--far from it, there are new stories on influenza out every day. Rather, there are just a lot of people out there covering it, and covering it well. However, it's been an unusually busy few days on the influenza front, so I thought I'd update after the jump.
First, though much of the mainstream media has lost interest in avian influenza, scientists are still busy keeping an eye on things--and H5N1 is still spreading. Human cases have now been reported in Pakistan,…