Swine flu–deja vu all over again?

Back in 2007, I wrote about an outbreak of swine influenza from an Ohio county fair. The peer-reviewed paper analyzing the swine influenza isolated from that outbreak has just recently come out. From the abstract:

The swine isolate, A/SW/OH/511445/2007 (OH07), was evaluated in an experimental challenge and transmission study reported here. Our results indicate that the OH07 virus was pathogenic in pigs, was transmissible among pigs, and failed to cross-react with many swine H1 anti-sera. Naturally exposed pigs shed virus as early as 3 days and as long as 7 days after contact with experimentally infected pigs. This suggests there was opportunity for exposure of people handling the pigs at the fair. The molecular analysis of the OH07 isolates demonstrated that the eight gene segments were similar to those of currently circulating triple reassortant swine influenza viruses. However, numerous nucleotide changes leading to amino acid changes were demonstrated in the HA gene and throughout the genome as compared to contemporary swine viruses in the same genetic cluster. It remains unknown if any of the amino acid changes were related to the ability of this virus to infect people. The characteristics of the OH07 virus in our pig experimental model as well as the documented human transmission warrant close monitoring of the spread of this virus in pig and human populations.

Meanwhile, I mentioned yesterday that gene sequences from the new H1N1 virus had been released. Sandy has taken a look at some of these, and compared them with H1N1 and H1N2 viruses from humans and pigs.

Yes, there is a point to the juxtaposition of these two points, and it’s big–after the jump…
Continue reading “Swine flu–deja vu all over again?”

Swine flu link roundup

Revere on quarantine versus isolation. This is a topic I’ve covered previously (here) as well, and an important distinction (though the two are often muddled together in the press).

Christine Gorman talks about getting the facts straight on swine flu, and offers up many additional resources to keep you updated.

Skepchick provides “Things More Likely to Save You From Swine Flu Than Homeopathy”. Colon cleanse and chiropractic are noticeably absent…

1976 swine flu Public Service Announcements. They don’t make ’em like that anymore… (h/t http://twitter.com/tomburket)

Finally, my colleague, Dan Diekema, a hospital epidemiologist extraordinaire here at the University of Iowa, has started a new blog: Controversies in Hospital Infection Prevention. Obviously, swine flu has been the big discussion in this area over the last few days, and Dan and his co-blogger, Michael Edmond, have several posts on swine flu and infection control. Stop by and check it out…

Swine flu: Central & South America, Asia, New York update

Stories in Spanish: Costa Rica becomes the first Central American country to confirm swine flu (“gripe porcina”). A 21 year old who had traveled to Mexico is in stable condition. An additional 16 cases were examined but were negative. Brazil is also examining 11 travelers; cases are also being examined in Panama, Honduras, Argentina, and Uruguay, and Chile.

In Asia, South Korea is examining a possible case, while China’s stepped up its efforts to look for cases (and blocked import of pork from the US and Mexico).

Most of the cases that are being examined have traveled to Mexico recently, but secondary spread may be occurring in New York City. 45 cases have been confirmed to date, but many more are suspected or have been alluded to in news reports. This extended human-to-human chain of transmission is the worrisome part–if this is efficient, it’s going to be much more difficult to get ahead of the virus and minimize spread. Expect much focus in the coming days and weeks to be on contacts of infected cases, in an effort to determine the frequency of secondary transmission…

Swine flu and snake oil

I was introduced to snake oil salesmen at a young age. My mother was diagnosed with multiple sclerosis when I was in kindergarten, and while she has mostly followed the advice of her neurologists, she’s also looked into “alternate” therapies, ranging from the relatively harmless (massages, oils, etc.) to more invasive methods (chelation, all sorts of expensive but worthless supplements). Some of these I’ve been able to talk her out of (and I personally think her current doctor–NOT a neurologist–is a total quack), but others she’s taken because, hey, “what’s the harm?” It’s frustrating to see money and hope wasted on bogus treatments.

Of course, it’s not only chronic conditions that appeal to these salesmen; they’re all over infectious disease as well, peddling unproven treatments to “boost the immune system” and discouraging the use of conventional treatments. It appears that swine flu is their newest target (h/t Orac), as chiropractic is said to have “miraculous” results and colon cleanses, likewise, “work miracles”. The authors both suggest that their fave treatment, therefore, should also be used to treat/prevent swine flu. After all, claims Kim Evans (author of Cleaning Up! and the creator of The Cleaning Up! Cleanse, a powerful body cleanse):

And it’s my understanding that many people who took regular enemas instead of vaccines during the 1918 pandemic made it out on the other side as well.

Ah, someone has been studying up on their Whale.to 1918 flu pandemic revisionist epidemiology. Fantastic.

Seriously, HuffPost? This is what you want to promote? What’s next–lizard men?

How long does it take to sequence an influenza virus?

…asked Joe. Answer: only a few days to sequence, clean up the data, and submit to NCBI. Seven H1N1 swine flu sequences are up (H/T Jonathan Eisen). I’ve not had a chance to crack anything open yet, but I hope to see some analysis from more of the genomics geeks soon…However, one bummer is that they don’t have any from the Mexico cases available–and particularly, any sequence data from any of the fatal cases. These will be helpful to see if there are any point mutations that could possibly account for a virulence difference between the Mexican and US cases. (Unlikely, I’d guess, but it would be nice to check it out…)

Swine flu update: Europe and the bottom of the world

For those of you looking to follow new cases (most of them suspected at this point, not confirmed), a great resource is HealthMap. Reports are popping up of possible infections worldwide: Scotland, Spain, Australia, and New Zealand. Certainly additional possible cases will be showing up over the coming days as well.

One thing I’ve seen mentioned (including here in the comments) is a question about the unlikelihood of a flu outbreak in Mexico in late April. Isn’t influenza a cold-weather bug? Well, yes and no. Influenza circulates year-round at a low level, but it lasts longer in the environment in colder temperatures with lower humidity, meaning more people can potentially be infected by each infected person, leading to our seasonal outbreaks. However, recall that in 1918 the first cases began in winter/spring 1918, and then it came back with a vengeance beginning in August, and really taking off by October. Additionally, we essentially have no barriers to worldwide spread, and there are already potential cases in New Zealand and Australia (where winter is setting in).

Again, we don’t know right now whether this will die out or become the next pandemic, but the spring timing of this doesn’t necessarily limit the virus’ potential.

Swine influenza–older posts

While there’s interest and some new readers, I figured I’d link some of my older posts on swine influenza and pandemic influenza in general for some additional background information and history. Keep in mind that these are unrelated to the current outbreak.

Pandemic influenza series (a bit dated, but still some good information in there, including an overview of 20th century pandemics).

Asymptomatic swine flu infections in farmers

Swine flu in Ohio fairgoers

Iowan has swine flu

New swine influenza virus detected

Masks and influenza

Masks and influenza part II

Swine flu: 20 US cases now identified [UPDATED–6 Canadian cases also confirmed]

According to new information from the CDC, in addition to the 2 cases in Texas, 7 in California, and 2 in Kansas, the 8 in New York have now been confirmed, and an additional case has also been confirmed in Ohio (I’ve not seen any info on that case)–UPDATED below. Investigations are apparently ongoing in at least 2 Canadian provinces, also (British Columbia and Nova Scotia). An investigation is also ongoing in New Zealand after teenagers took a trip to Mexico and have shown flu-like symptoms.

Concerning to say the least, but crof and revere both have some excellent posts to keep things in perspective. I’ve hated the screaming headlines at many of the MSM sites, and Crawford has a great post encouraging calm. revere, meanwhile, has a nice overview of influenza and world travel, and what we should be focusing on now that it seems the genie is already out of the bottle.

Again, this is a fast-developing story; some of this information will probably be out of date by a few hours after I post this, so stay tuned…

UPDATED: found some information on the Ohio case, from the Toledo Blade:

The Ohio Department of Health says a 9-year-old boy who recently traveled to Mexico on vacation with his family has a confirmed case of swine flu.

Health department spokesman Robert Jennings said Sunday the boy is recovering at his home in Elyria, in northern Ohio’s Lorain County. The child’s name was not released.

Jennings says the Centers for Disease Control confirmed the case, but officials do not know if the child has the same deadly strain of swine flu that has killed up to 81 people in Mexico.

Jennings says the boy displayed typical symptoms of the flu, including a sore throat and body aches. Jennings says the child returned from Mexico within the past two weeks.

Jennings says the boy’s relatives are being tested for the disease, but they currently do not have any symptoms.

Nova Scotia cases have also been confirmed:

Nova Scotia’s chief public health officer says the east coast Canadian province has four confirmed cases of swine flu.

Chief Public Health officer Dr. Robert Strang says Sunday four students from King’s-Edgehill School in Nova Scotia ranging in age from 12 to 17 or 18 are recovering. All of them had what he describes as “very mild” cases of the flu.

2 cases in British Columbia also confirmed:

B.C.’s Centre for Disease Control on Sunday confirmed cases of swine flu involving two people from the province who recently returned from Mexico.

Swine flu: a quick overview–and new New York and Kansas cases

Sorry for the radio silence–I’ve been working on grants and manuscripts like a fiend, and so have tried to limit as many distractions as possible (which, unfortunately, includes blogging). However, the swine flu news is right up my alley, so I do just want to say a few words about it, and point you to some excellent stories already up elsewhere.

First, in case you’ve not been paying attention to the news in the last few days, there have been 8 reported cases of swine influenza infections in humans (6 in California and 2 in Texas, with additional suspected cases) and reports from Mexico suggesting as many as 1000 ill and 68 dead from influenza in the past month or so. Of the Mexican cases, a dozen thus far have been confirmed to be the same strain as the US swine flu strain from California/Texas.

What does all this mean? Much more after the jump.
Continue reading “Swine flu: a quick overview–and new New York and Kansas cases”