Posted on 05/21/2009 10:09:41 PM PDT by john in springfield
Mexico City ends swine flu alert, no cases in week
May 21 02:49 PM US/Eastern
By ISTRA PACHECO
Associated Press Writer
MEXICO CITY (AP) - Mexico City lowered its swine flu alert level from yellow to green on Thursday, and the mayor said "we can relax" now that there have been no new infections for a week.
Mayor Marcelo Ebrard said the change means the risk of contagion is low, the situation is under control and the images of countless people wearing blue surgical masks in cars, sidewalks, restaurants and theaters can be consigned to history.
City Health Secretary Armando Ahued said nobody has been hospitalized with respiratory infections in the last three days, and no swine flu cases have been confirmed since May 14. "We are seeing a 96.1 percent drop in cases, and that's why we are dropping the alert level to green today," Ahued said.
(Excerpt) Read more at breitbart.com ...
From my POV this is very, VERY good news. The new flu still seems to be spreading in the US, but definitely appears to me to have slowed down here as well.
Apparently a seasonal effect is kicking in. It was not entirely clear to what extent this might or might not happen.
It remains to be seen what will happen this fall. Unfortunately we're not likely to have vaccine available for a second wave, and there's also the potential of the new H1N1 mixing with the seasonal variety and thus developing Tamiflu resistance.
What I'm actually hoping (which off the top of my head sounds like a plausible scenario) is that as the virus mutates into potentially both more lethal and less lethal forms, the spread of any more lethal forms will be repressed more effectively than the spread of less lethal forms and we will see an overall weakening of the disease as a result. Of course, sometimes in the past it's turned worse instead of better (e.g., 1918). But maybe our spread control has improved enough to cause a weakening effect...?
That’s nice.
I still wouldn’t go there.
From PLoS Pathogens
Influenza Virus Transmission Is Dependent on Relative Humidity and Temperature
from the link:We found that low relative humidities of 20%–35% were most favorable, while transmission was completely blocked at a high relative humidity of 80%
I got the link via FReepmail, and have not had time to share it.
ping...
That’s some very interesting and potentially valuable information.
In fact, I was just wondering why the sudden decrease in cases in Mexico, as I knew April was one of the warmest months. But maybe it’s humidity:
“April and May are the warmest months because summer temperatures are ameliorated by a rainy season that begins in late May and lasts until early October. During that time the normally dry upland basin becomes verdant and its air cool and clean.” (Encyclopedia Brittanica)
It would be interesting for someone to sort out how much of seasonal influenze effect is typically caused by temperature, how much by humidity, how much by blood levels of vitamin D, how much by school being out, and how much by something else.
Well, it’s flu season in South America now. It’s cold, raining, snowing and generally shitty because it’s called winter down there.
My main point, really, is that if this is the trend we’re seeing in Mexico City, then probably and hopefully we can anticipate that same trend to kick in here in the US over the next couple of weeks.
As of about a week ago, cases were increasing by 40% every single day, and there really was no visible sign of any seasonal dropoff. That was concerning, as it only takes a few weeks at that rate to basically infect the entire country. As late as this morning I was still not as optimistic as I am now about what the next several weeks would bring.
This news gives good reason to believe that the tide has turned for the immediate season. Assuming that this positive trend continues (and offhand I can’t think of any reason for it not to), then the question will be what this virus now does in the southern hemisphere, how it mutates, how forcefully and how quickly it returns in the fall, what the virulence and spreadability are like at that point, and how soon vaccine is available in quantity.
Yes, it’s starting to look like the next major act will be played out in the southern hemisphere...
Who knows? A lot of people from SA fly here to vacation during their winters.
Onlinejournal.com material is not welcome on FR.
k
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