Daily Archives: April 9, 2013

The new bird flu: Is it serious?

There is a new outbreak of a bird flu in eastern China, referred to as H7N9. The first thing you need to know is that human populations have not been previously exposed (to any degree) to H7 or N9 type virus, so if this virus were to mutate in such as way as to spread human to human, the result could be very serious. Moreover, the “H” component of the virus is thought to have a genetic sequence that is known to readily mutate into form that would be target (bind to) human rather than bird cells.

The virus has been found in chickens, pigeons, and ducks in markets where live birds are sold. It is not known if there is a particular species harboring the virus, acting as a reservoir, but chances are there is one species of bird out there somewhere that has been passing the virus to other birds probably in the context of the live bird markets. It is possible that the reservoir is a domestic bird or a wild bird.

Health officials are concerned because the number of human cases seems to be rising dramatically. A few weeks ago a few people were infected and there had been a few deaths. The most recent information, probably a few days old, indicates that 24 humans have been infected of whom 8 have died, across 11 cities separated by hundreds of kilometers, but with most of the cases in a couple of locations including the vicinity of Shanghai.

Also, birds with the virus appear healthy. This is different than the more famous H5N1 bird flu, which made birds sick and thus made it possible to survey for areas where the virus was around.

The more pessimistic interpretation of all of this suggests that this is a “perfect storm” of factors to start a real pandemic. The virus is spread over a large area in heavily populated areas. The most direct ways of identifying potential reservoirs is unavailable. Humans are not predisposed with any sort of immunity to the virus. Genetically, the parts that would make it a human virus are primed to do so. The mortality rate is very high. And so on.

The more optimistic interpretation would note that a fast spreading disease like this is more likely to wipe itself out quickly. A high mortality rate is often seen in the early days of an emerging disease. People got sick and died because no one was expecting it, but with a better planned response moving forward, that rate should drop. We know a lot more about flu virus genetics and transmission than even just a few years go, so the science is a powerful tool. Most importantly, there is no human to human transmission of the virus at this time. Unless that happens, this is an important public health crisis and will have impacts on the economy linked to birds, but we are not all going to die. From this. And so on.

I’m not sure if this is behind a paywall, but most of the information here is from this piece in Nature. See also this from the CDC. CDC calls this an “evolving situation.” Haha.

Photo Credit: IvanWalsh.com via Compfight cc

Global Warming Skepticism In Decline

There is a new Gallup poll that together with earlier data from Gallup provides some interesting information about attitudes in the US about global warming.

Earlier polls have shown increase and decrease in concern about global warming, and changes in what people think of news about climate change and the severity of the problem. Recently, there has been a shift towards greater concern which follows a low point, which, in turn, follows a period of global concern.

One question involves reading off a list of specific concerns related to global warming and asking participants to rank their concern over that issue, and then averaging the responses. This produces a graph of percentage of “worry” at higher levels that looks like this:


According to Gallup, the breakdown underlying this graph indicates that

33% of Americans worry about global warming “a great deal,” 25% worry “a fair amount,” 20% “only a little,” and 23% “not at all.”

The take home message here is that 58% of Americans see global warming as serous while a mere 23% see it as not an issue at all. Denialists together with those who just don’t know are in a small minority. Also, 54% of Americans acknowledge that the effects of global warming have already started.

Even though a mere 23% of respondents don’t seem to think global warming is a problem, even fewer, 15%, think that it “will never happen” while 81% think that the effects of global warming have already begun or are to be expected in the future. Here’s the graph of those responses over time:


Related to all this is the way Americans view news stories about global warming. A plurality, but a declining number, tend to see news stories as exaggerated, but the combined number who see stories as either correct or underestimated is over half. Notably, those who see stories of global warming in the news as underestimates of the severity of the problem have been increasing in number in recent years.


Prior to a recent nadir in about 2010, over 60% of Americans recognized that there is a scientific consensus that Global warming is occurring. This number has recently risen from that recent dip to 52% nearly to it’s high point of 65% and is now as 62% and perhaps rising. Only a tiny percent responded that they think most scientists do not believe global warming is occurring.


The number of people who understand that humans are the primary cause of global warming also underwent a dip aroun 2010, and that number is rising again to pre 2010 levels.


And finally, a large percentage of Americans recognize that the effects of global warming will have a negative impact on their lives:


Gallup is expected to release information on attitudes about global warming based on political orientation. The present study can be found here.

Meanwhile, we should note that the scientific consensus is much stronger than the public consensus. It looks more like this (from here):