infectious disease
tsmith | January 23, 2009 A little over a year ago I put a post up documenting research out of Canada which found methicillin-resistant Staphylococcus aureus (MRSA) in Canadian pigs. This had also been seen in Europe (with a lot of research coming out of the Netherlands). What I didn't note at the time was that we were gearing up to start some sampling of our own on area swine farms. Some of you saw that we presented the results of that research last year at ICEID and ASM; now the paper is out describing our pilot project in PLoS ONE. (Note: the paper was available earlier, but now they seem to have removed it…
revere | January 22, 2009Readers want to know what I think about the bird flu situation in China, where four human cases have been reported in the last couple of weeks. I haven't said anything about it so far, which is normal for me. I usually like to wait for more information. There are dedicated and smart flu bloggers out there who spend more time collecting scraps of information than I do. Check out fluwiki forum and CureEvents, for the latest word, all accurately reported by top rank flu bloggers like crof and Mike and a number of others (it is dangerous to start naming people because you inevitably leave out…
revere | January 17, 2009Prions, the infectious proteins that are the likely agents of Kuru, variant Creutzfeldt-Jakob Disease ("Mad Cow Disease"), scrapie in sheep and Chronic Wasting Disease (CWD) of elk and deer, are the zombie undead of pathogens. Almost nothing we do inactivates them. They withstand fire, autoclaving, radiation and all manner of chemical disinfectants. Except for the mineral birnessite:
That the birnessite family of minerals possessed the capacity to degrade prions was a surprise, [Joel Pedersen, a University of Wisconsin-Madison environmental chemist] says. Manganese oxides like birnessite are…
revere | January 12, 2009DemFromCt's excellent post at DailyKos alerted us to the fact that this year's vaccine appears to have a mismatched influenza B component. Each year vaccine makers try to anticipate the strains that will be circulating 6 months hence, based on surveillance data. They have been fairly good with their guesses but things seem to be getting more complicated in recent years and mismatched strains are becoming more common, that is, the vaccines don't protect as well or at all against the strains that are actually circulating. There are three strains in the yearly "flu shot," two influenza A strains…
revere | January 11, 2009We've been blogging about flu for over four years. It's not a rare topic these days. But when we started we only found two other bloggers with an interest in the subject. One was the late (and much missed) Melanie Mattson at Just a Bump in the Beltway blog. The other was DailyKos frontpager DemFromCT. Dem is still on the front page at dKos and still on top of flu. He is one of the blogosphere's pre-eminent flu experts, being not only an accomplished blogger but a medical professional whose specialty is pulmonology. He sees flu up close, in the lungs of his patients. So whenever Dem writes…
revere | January 9, 2009You may be surprised to learn (I was) that the US is having a large (almost 400 people) multistate (42) salmonella outbreak (S. typhimurium, often but not always associated with poultry and dairy products). So far 67 hospitalizations, with patients spanning the age spectrum (ages 1 to 103).DNA fingerprinting has established all cases are related (a common source or sources). Oh, and one more thing. It didn't just begin. Apparently it's been going on since sometime in September.
Like the plat du jour, this is the salmonella outbreak du jour. Last summer we were treated to the tomatoes-cilantro…
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…
revere | December 28, 2008As far as the world is concerned, if any day can be said to be bird flu's birthday, it's today. The disease of birds doctors call influenza A subtype H5N1 may have had a long gestation period, but we're not sure how long. A form of the virus deadly to poultry was isolated from a goose in southern China (Guangdong province) in 1996, marking the first time the highly pathogenic form of the H5 bird virus poked its head above water for us to see. How long it had "been around" before that we don't know. Then in May, 1997, a three year old tot in Hong Kong came down with a flu-like illness that got…
revere | December 22, 2008It's influenza-like illness ("ILI") season again. We just call it flu season but in fact there are a lot of respiratory viruses running around besides the flu virus that look like flu. Recently we discussed one of the others, the human metapneumovirus (HMNV). It's been around infecting us for over a century but wasn't identified until 2001. One we've known about a little longer (1956) is respiratory syncytial virus (RSV), a major cause of respiratory infections in children and increasingly in adults, especially the elderly. Like influenza and HMNV, RSV is a negative sense single stranded RNA…
revere | December 13, 2008Whether they are called the White House Press Secretary or the regime's Information Minister, they seem to have in common one characteristic: they are professional liars. It goes without saying that all of Bush's press secretaries have been blatant liars, but it's also true of Clinton's and virtually very one of their predecessors. Some of them have been much more likable than others and when they lied made my hackles rise less, but they were still professional liars and why anyone believes what they say is one of the big mysteries. I have to keep reminding myself that our "Information…
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…
revere | December 8, 2008Blogging will be light for the next day or so because the eventuality I feared most, that I would get the day care incubated norovirus-like illness that grandson #2 incubated, has come to pass. I had to cancel an extremely important trip to a scientific meeting in California. There is no hope I'd make it and I'd probably infect everyone on the plane t rows up and 5 rows back, not to mention my colleague I was going to share a room with. So I am super miserable and now my son-in-law is down with it and my daughter is feeling "seriously queasy." Mrs. R. is morosely waiting for the other shoe to…
revere | December 7, 2008I vaguely remember a medical school lecture about dracunculiasis, also known as Guinea Worm Disease. Also called the "fiery serpent" these are very long worms that grow in people and then the females get hungry and start to burrow out of them, sort of like Alien but not quite as quickly or as dramatically nor out of their chest. Usually out of the tops of their feet. Here are the basics of the life cycle:
When I first heard about dracunculiasis the world had many millions of people suffering this debilitating horror. In 1986 the Carter Center, the creation of former President Jimmy Carter,…
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…
revere | December 4, 2008The 53 year old South African businessman arrived in Rio de Janeiro on November 23. Two days later he began to feel unwell. Today he was returning to South Africa -- in a zinc lined coffin:
Brazilian media reported officials as saying he may have been infected when he was a patient at a hospital in South Africa where four people died from a new strain of arenavirus, which also includes the germ that causes Lassa fever.
The health ministry said it had not confirmed that information, but said one of the suspected causes of death was the arenavirus, which is spread through the excrement or blood…
revere | December 2, 2008Cholera is a vicious disease. It can take a healthy person and kill him or her in a day by rapidly dehydrating them from a massive, watery diarrhea. The resulting electrolyte imbalance can lead to vascular collapse or cardiac arrest. Cholera is usually spread by fecally contaminated drinking water, and hence is completely preventable. It is also easily treatable by keeping the patient hydrated with the oral rehydration therapy, basically minimally fortified water. Yet this preventable and treatable disease is now epidemic in the country of Zimbabwe. Government sources admit to over 400 deaths…
revere | December 1, 2008The common cold is probably common because a lot of different viruses cause similar symptoms. We usually treat it symptomatically or just endure it. We rarely expend much time, effort or money identifying which virus caused it. As as a result we undoubtedly haven't identified all the viruses that can make us miserable in the inimitable way we identify as a "head cold." When we entered the 21st century, some 8 years ago, there were a lot of stories about what the future might bring and I was interviewed by a well known medical TV reporter (Dr. Timothy Johnson) about what I thought would happen…
revere | November 28, 2008In 1988 a 32 year old woman, 36 weeks pregnant, checked into a community hospital in Wisconsin. She'd had flu-like symptoms with a moderately high (spiking to 102 degrees F.) fever for the previous week. Three days before admission she started a cough that brought up sputum and a day before started to get short of breath. On x-ray both lungs showed a consolidated pneumonia in the lower lobes and she was started on broad spectrum antibiotics, transferred to a tertiary care hospital and started on assisted ventilation. Labor was induced and she delived a healthy baby, just over 6 lbs. Four days…
revere | November 22, 2008At least one little corner of the biodiversity problem seems to be doing well: biodiversity among deadly diseases. An outbreak of Ebola disease in Uganda in 2007 has now been shown to be caused by a previously unknown variant, now called Bundibugyo ebolavirus.
Ebola virus produces a particularly nasty kind of hemorrhagic fever. Richard Preston gave some gory descriptions in his 1999 bestseller, The Hot Zone. Case fatality ratios for Ebola are well over 50%, exceeding 90% [typo corrected] in some outbreaks. Ebola viruses are part of a viral family called filoviruses, that also includes Marburg…
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…