(Wed, 25 Nov 2009 15:31:16 +0000)
First came the headlines, Dateline Norway:
UPDATE 1-Norway says found H1N1 mutation in flu victims
Fri Nov 20, 2009 2:01pm EST
* 3 H1N1 cases found with potentially significant mutation * Two cases found among first fatalities in Norway
* Says disease’s mutation could cause more serious illness
* WHO says mutated virus sensitive to antivirals, vaccines
(Adds WHO statement in new paras 4-6; CDC comment paras 15-17)
OSLO, Nov 20 (Reuters) - Norwegian health authorities said on Friday they have discovered a potentially significant mutation in the H1N1 influenza strain that could be responsible for causing the severest symptoms among those infected.
“The mutation could be affecting the virus’ ability to go deeper into the respiratory system, thus causing more serious illness,” the Norwegian Institute of Public Health said in a statement.
There was no reason to believe the mutation had any implication for the effectiveness of flu vaccines or antiviral drugs made by groups such as Roche , GlaxoSmithKline, Novartis (NOVN.VX: and AstraZeneca, the authorities said. ( I would add BioCryst as well, makers of peramivir).
The World Health Organisation said that the mutation did not appear to be widespread in Norway and the virus in its mutated form remained sensitive to antivirals and pandemic vaccines.
A similar mutation had been detected in H1N1 viruses circulating in several other countries, including China and the United States, in severe as well as in some mild cases, it said.
“Although further investigation is under way, no evidence currently suggests that these mutations are leading to an unusual increase in the number of H1N1 infections or a greater number of severe or fatal cases,” the WHO said in a statement.
H1N1, a mixture of swine, bird and human viruses, has killed at least 6,770 people globally, according to its latest update.
In Norway the mutation was found in the bodies of two people killed by the virus and of one person made seriously ill. The two infected by the mutated virus who died were among the first fatalities from the H1N1 pandemic in Norway, the institute said.
It was unclear whether the mutated virus was transmitted among humans, the health authorities said.
“Based on what we know so far, it doesn’t seem like the mutated virus is circulating in the population, but rather that spontaneous changes have happened in the three patients,” director Geir Stene Larsen at the public health institute said in the statement.
Norway has seen relatively more fatalities in the flu pandemic compared to the size of the population versus other European countries, with 23 confirmed deaths.
Public health authorities have said this could be due to the country being hit early in the pandemic’s northern hemisphere winter wave, before a mass vaccination programme got underway.
“Nevertheless, it is important to study if there’s still something about the Norwegian fatalities that separate us from other countries, and that make us learn something that strengthens our treatment of the seriously ill,” director Bjorn-Inge Larsen at the Norwegian Directorate of Health said.
Dr. Anne Schuchat of the U.S. Centers for Disease Control and Prevention said, “This mutation has been seen sporadically.”
She said it is sometimes seen in patients who have mild influenza symptoms.
“I think it is just too soon to say what this might mean long term,” Schuchat told reporters in a telephone briefing. (bold mine) (Reporting by Richard Solem; Additional reporting by Stephanie Nebehay in Geneva and Maggie Fox in Washington; Editing by Matthew Jones and Louise Ireland)
Then the attention turned to Wales and North Carolina, where Tamiflu-resistant H1N1v has apparently spread person-to-person. Now Chinese superscientist and national hero Zhong Nanshan warns that the conditions are ripe for an H1/H5 hybird to emerge, possibly from China itself. From the Reuters story:
Zhong Nanshan, director of the Guangzhou Institute of Respiratory Diseases in China’s southern Guangdong province, said the presence of both viruses in China meant they could mix and become a monstrous hybrid — a bug packed with strong killing power that can transmit efficiently among people.
“China, as you know, is different from other countries. Inside China, H5N1 has been existing for some time, so if there is really a reassortment between H1N1 and H5N1, it will be a disaster,” Zhong said in an interview with Reuters Television.
“This is something we need to monitor, the change, the mutation of the virus. This is why reporting of the death rate must be really transparent.”
And finally, China itself reports at least eight cases of mutant H1N1v within its borders.
And our response should be: So tell me something I didn’t already expect?
Tamiflu-resistant H1N1 seasonal flu runs about 99%. Of course, there is no seasonal flu right now of any kind, anywhere in the world. that is one of the key differences between seasonal H1 and pandemic H1: Pandemic H1 can be beaten back by Tamiflu.
As for mutant H1N1v: Of course we would see mutations in the virus! That is why we need annual flu shots! Seasonal flu mutates beyond the ability of vaccines to protect us. This is referred to as “antigenic drift” and is well-known to all who have read this blog for any duration. I only mention it for all the new readers who are picking this blogsite up every day.
But the mutations in Norway are of special concern. That is because these mutations cause the virus to penetrate deeper into the lungs of its victims. And as you probably can guess, deeper is much, much worse. Once the virus lodges itself in the bottom of the lungs, it becomes much harder to eradicate.
This is one of the hallmark signs associated with H5N1 bird flu. Yes, bird flu is exceedingly hard to catch. But once caught, if medical help and liberal doses of antivirals are not immediately administered, there is diminished hope of recovery.
So the revelation that the “Norwegian mutation” caused death in two patients and severe illness is disconcerting. But to me, not unexpected. After all, what disease is moderating itself these days? This virus is already pretty “mild” in the overwhelming number of cases. Down for a few days and then back to work, or school, or whatever. So anyone who thought this virus might become even milder has, at best, a 50% chance of being right.
Or a 50% chance of being wrong.
I err on the side of a tougher disease in the long run. I ask the question again: What disease is moderating itself these days? Ebola? SARS? MRSA? Dengue? Adenovirus? They have even detected a relatively new strain of rhinovirus, called Rhinovirus C, in Pennsylvania. A newspaper in Philadelphia reported that tests showed a roughly equivalent number of people catching rhinovirus as catching influenza. Only this rhinovirus (C) is quite a doozy. And I have often wondered how many of the people testing negative for H1N1v might actually been suffering from Adenovirus 14.
In what is an interesting revelation, the WHO is also reporting that similar mutations to the Norwegian Mutation have been detected in Mexico, the United States, Brazil, Japan, and the — Ukraine.
If you did not notice how the WHO parsed its language during the Ukranian Outbreak, it said:
17 November 2009 — Preliminary tests reveal no significant changes in the pandemic (H1N1) 2009 virus based on investigations of samples taken from patients in Ukraine. Analyses are being performed by two WHO influenza collaborating centres as part of the global influenza surveillance network.
Preliminary genetic sequencing shows that the virus is similar to the virus used for production of the pandemic influenza vaccine, reconfirming the vaccine’s efficacy at this time.
The parsing of those words is important. Saying there were no significant changes means there were changes but not changes that, in the opinion of two collaborating WHO centers, meant anything. They also said that the virus had not drifted beyond the target as specified by the original virus used for the manufacture of vaccine.
Now here is the AP story on China:
China reports 8 cases of mutated swine flu virus
By GILLIAN WONG (AP) – 2 hours ago
BEIJING — China has detected eight people infected with mutated forms of the swine flu virus, a health official said Wednesday, but flu drugs and vaccines still work against it.
Flu viruses mutate easily, and scientists have been closing watching for signs that the swine flu virus is changing, which could make it more dangerous or more infectious.
Shu Yuelong, director of the Chinese National Influenza Center, told the official Xinhua News Agency that the mutated swine flu virus found in China was in “isolated” cases in the mainland, is not resistant to drugs and can be prevented by vaccines.
The report did not provide any more details, such as when the cases were detected and if they were linked to any deaths. Calls to the National Influenza Center rang unanswered while the Health Ministry did not immediately respond to a faxed list of questions.
The World Health Organization’s spokeswoman in Beijing, Vivian Tan, said the agency had no information on the cases mentioned in the Xinhua report Wednesday.
On Friday, the WHO said it was looking into two deaths and one severe case linked to variant swine flu in Norway, after that country’s Institute of Public Health announced that the mutation could possibly cause more severe disease because it infects tissue deeper in the airway than usual.
The same mutation has been found in both fatal and mild cases elsewhere, including in Brazil, Japan, Mexico, Ukraine, and the United States, said the WHO. (bold mine)
Tan said the agency is aware of three such cases in China that occurred in June and July that were similar to the cases being investigated in Norway.
“We are concerned, but realize that influenza viruses, including A/H1N1, are relatively unstable and change easily, especially as they infect more people,” Tan told The Associated Press. “Some mutations can have minimal effects on how a virus functions, while other mutations can create important changes with significant public health impact.”
China’s Health Ministry said Wednesday that 51 swine flu deaths were reported last week, bringing the total number of fatalities in the country to 104.
OK, let’s recap. This is the kind of informed analysis you come to this site for, right?
H1N1v produces mutant offspring practically every time it replicates itself. That is because, as an RNA virus, it does not have the double helix quality control of a DNA virus. That is why there is no universal flu vaccine. And that is why, eventually, even the H1N1v pandemic vaccine will become ineffective. Be it three months from now, or three years, it will inevitably be ineffective.
But there have been key mutations spotted in multiple nations almost simultaneously. These mutations have the effect of pushing H1N1v deeper into the human lung, similar to the effect of H5N1 bird flu. It is not known if any of the 4,000 deaths in this country are due to this mutant strain of H1N1v, although that should be the very next question anyone asks the CDC.
In order for this mutation to become more pronounced, it must have some sort of indefinable quality that makes it the preferred strain of virus. It has to break out more frequently, in more places, and infecting more people. It has to move efficiently — something the Norwegian doctors do not think is happening. Remember that influenza’s goal is coexistence, not slaying its host. Inasmuch as you can ascribe any thought process to something that science does not even want to classify as a life form!
But if this mutation becomes more pronounced, and happens in more and more places, the potential exists for it to make some headway and become the dominant substrain of H1N1v. I don;t know what we call it at that point; I think the protocol would be to call it A/H1N1/Norway/2009 or something along those lines.
All this serves as a reminder that this pandemic is a looooong way from being over. Weekly case numbers are misleading and produce false hope. The Florida Department of Health is not even producing an update until December 3, which I think is a jolly good idea. By the way, Florida’s average age at death from swine flu is now north of 55. Seven died last week in the Sunshine State, and none of them were under the age of 38.
So do not be surprised if you continue to hear about mutations, especially mutations that seem to cause more serious disease. There was a 50/50 chance it would wind up that way. It should ,however, spur you and your loved ones, co-workers, friends and teammates to all seek the H1N1v vaccine. It is safer than the virus.
But scientists need to tell us where those mutations took place, and how it affected the death totals. For instance, southern Brazil had a mutation in the early stages of the pandemic, specifically in Sao Paulo. Brazil also had a higher case fatality rate in the southern portion of the nation, where Sao Paulo is located. Coincidence?
Likewise, in the United States, were any deaths attributable to this mutation? How about in the Ukraine, where there was something akin to panic in the streets and their public health people were claiming a fusion of H1N1v with parainfluenza and pneumonic plague?
Lots of unanswered questions. Lots of room for speculation. And lots of pandemic activity remaining to be played out on the global stage.
We would be wise to heed Zhong’s words. And we need to recognize this pandemic is anything but “mild.”
