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Dengue Fever is headed to the United States.

From Bloomberg.com: http://www.bloomberg.com/apps/news?pid=20601087&sid=aWqWwATk6DpA&refer=home

Dengue Fever Threatens U.S. as Tropical Bugs Spread (Update2)

By Catherine Larkin

Jan. 8 (Bloomberg) -- Dengue fever, a potentially deadly virus usually found in the tropics, could begin spreading widely in the U.S. as mosquitoes that transmit the disease move into more states, according to two leading epidemiologists.

The disease has already struck Hawaii, Texas and Puerto Rico after decades of absence in the U.S., Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, and colleague David Morens write in the Jan. 9 Journal of the American Medical Association. They expect the threat to persist with increased air travel and urban development.

More than 760,000 cases of dengue and almost 20,000 cases of its deadly form, dengue hemorrhagic fever, were reported in the Americas in the first 11 months of last year, according to the Pan American Health Organization. With no specific treatments or proven vaccines to prevent the infection, an outbreak could overwhelm communities, Fauci and Morens said.

``This is an important problem, and our options for control and prevention at the moment are not very good,'' said Morens, Fauci's senior scientific adviser, in a phone interview today. ``It's easy to forget when a disease has been away for a long period of time.''

Dengue can be caused by four kinds of flavivirus, a family of viruses that also includes yellow fever and West Nile. The Aedes mosquitoes that transmit dengue have been around for hundreds of years and have re-emerged in greater numbers since efforts to prevent yellow fever waned in the 1970s, according to the U.S. Centers for Disease Control and Prevention.

Climate-Change Effect

Increases in rainfall, temperature and humidity caused by global warming also favor the spread of mosquitoes. These types of weather changes may more than double the number of people exposed to dengue worldwide by 2080, according to the United Nations' 2007-2008 Human Development Report.

The World Health Organization estimates that more than 50 million cases of dengue infection occur each year. The flu-like illness leads to about 500,000 hospitalizations, mostly in children, and at least 2.5 percent of patients die.

Symptoms include high fever, headaches, joint and muscle pain, vomiting and a rash. Usually people with dengue recover within two weeks, according to the National Institutes of Health. The infection can be life-threatening when it turns into dengue hemorrhagic fever, which causes bleeding from the nose, gums or under the skin, or dengue shock syndrome, which causes massive bleeding and shock, according to the NIH.

The National Institute of Allergy and Infectious Diseases, based in Bethesda, Maryland, allocated $33.2 million in the fiscal year ended Sept. 30 for research on dengue and the development of vaccines, medicines and tools to diagnose the disease, according to a statement released today.

To contact the reporter on this story: Catherine Larkin in Washington at clarkin4@bloomberg.net .

And from Reuters: http://www.reuters.com/article/scienceNews/idUSN0847856420080108?feedType=RSS&feedName=scienceNews

Tropical dengue fever may threaten U.S.: report

WASHINGTON, Jan 8 (Reuters) - Dengue fever -- a tropical infection that usually causes flu-like illness -- may be poised to spread across the United States and urgent study is needed, health officials said on Tuesday.

Cases of the sometimes deadly mosquito-borne disease have been reported in Texas and this may be the beginning of a new trend, said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, and his senior scientific adviser, Dr. David Morens.

A warming climate and less-than-stellar efforts to control mosquitoes could accelerate its spread northwards, they cautioned.

"Widespread appearance of dengue in the continental United States is a real possibility," they wrote in a commentary in the Journal of the American Medical Association.

"Worldwide, dengue is among the most important reemerging infectious diseases, with an estimated 50 to 100 million annual cases, 500,000 hospitalizations and, by World Health Organization estimates, 22,000 deaths, mostly in children."

They compared dengue to West Nile virus, which first appeared in New York in 1999 and has now spread to the entire continental United States, Canada and Mexico. West Nile killed at least 98 people in the United States last year.

Both viruses are carried by mosquitoes. Dengue can be carried by the Aedes albopictus or Asian tiger mosquito -- first seen in 1985 in the United States -- as well as the more common Aedes aegypti species.

Most people infected with a dengue virus have no symptoms or a mild fever. It can cause minor bleeding from the nose or gums, but can also cause severe fever and shock and without treatment can kill.

"The combined effects of global urbanization and increasing air travel are expected to make dengue a growing international health problem for the foreseeable future," Fauci and Morens wrote.

(Reporting by Maggie Fox; editing by Julie Steenhuysen and Todd Eastham)

Could Florida and the Southeastern United States be added to the list soon, because of the proximity to the Caribbean, cruise ship passengers being bitten and taking the virus home to their home states, combined with the resurgence of Dengue in Puerto Rico?  Unknown but quite possible.  Perhaps even likely.  We certainly don't suffer from a lack of mosquito activity.  And look at the epidemics of norovirus that rage routinely now on cruise ships everywhere.  Maybe that DEET repellent should be required slathering when passengers disembark at tropical ports, especially San Juan, Puerto Rico.

The global press is fawning over today's bird flu-related statements of Bernard Vallat, head of the World Organization for Animal Health, or OIE.  Here is the MSNBC story, culled from, among other sources, Reuters and AP:

Were bird flu fears overblown?

PARIS - Fears of a flu pandemic originating from the deadly H5N1 bird flu virus were overblown, the head of the World Organization for Animal Health said Thursday.

The Paris-based body — an intergovernmental organization responsible for improving animal health worldwide — has been at the forefront of global efforts to monitor and fight H5N1, which scientists have tracked because they fear it may mutate into a human flu virus that starts a pandemic.

But "the risk was overestimated," said Bernard Vallat, director general of the animal health organization, also known as the OIE.

Vallat said the H5N1 virus has proved extremely stable, despite concerns that it could mutate into a form that could spread easily among humans.

"We have never seen such a stable strain," Vallat said.

He said concerns a few years ago that a flu pandemic from H5N1 might be imminent lacked scientific proof.

"It was just nonscientific supposition," he told reporters.

Prepare for pandemic
At the same time, the United Nations influenza coordinator said that governments around the world need to do more to prepare for the dramatic economic impact of the next flu pandemic.

On Thursday David Nabarro said his team had recently collected information from nearly 150 countries to see how prepared they were for a pandemic and the picture was mixed.

“Most countries have now focused on pandemic as a potential cause of catastrophe and have done some planning. But the quality of the plans is patchy and too few of them pay attention to economic and social consequences,” he told BBC radio.

“The economic consequences could be up to $2 trillion -- up to 5 percent of global GDP removed,” he said, reiterating previous World Bank and UN estimates.

Nabarro will deliver a lecture at the London School of Economics later on Thursday on the global state of preparedness for any pandemic.

Father infected by son
Separately, a Chinese man who died of bird flu last month likely passed the disease on to his father, but there is no evidence the virus mutated into a form which can be easily passed between humans, an official said Thursday.

The man in the eastern province of Jiangsu was diagnosed with the H5N1 strain of bird flu days after his 24-year-old son died from the disease.

This rare case of two family members struck by the disease drew concern from health authorities, because humans almost always contract H5N1 from infected birds.

H5N1 has infected more than 340 people and killed at least 212 since 2003, mostly in Asia. The virus strain does not easily spread between people, however, and most patients had been infected through close contact with sick poultry.

With the world’s biggest poultry population and millions of backyard birds, China is at the centre of the fight against bird flu. There have been other cases of human infection without confirmed outbreaks among birds in the same area.

The latest cases in China brought the number of confirmed human infections of bird flu in China to 27, with 17 deaths.

'Always be a risk'
While playing down concerns of a pandemic, Vallat said bird flu "will always be a risk" — not just H5N1, but also other strains that could mutate and become more virulent for animals.

He said vaccination campaigns were needed in countries where H5N1 has become endemic, including Indonesia, Egypt and, to a lesser extent, Nigeria.

Risks from H5N1 would be "greatly diminished" if the virus were eradicated in these countries, which have become "reservoirs" for bird flu, he said.

The Associated Press and Reuters contributed to this report

http://www.msnbc.msn.com/id/22590623/

An AFP wire story expands somewhat on Monsieur Vallat's comments:

H5N1 bird flu virus reassuringly stable: animal health chief

PARIS (AFP) — The H5N1 virus that causes deadly avian flu has proven remarkably stable and action to curb outbreaks of the disease are highly effective, the head of the world's paramount agency for animal health said here Thursday.

Since the end of 2003, mutation of the H5N1 virus so that it can be easily transmissible among humans has been a nightmare for the world health community, raising concerns of a global influenza pandemic that could claim tens of millions of lives.

But Bernard Vallat, director general of the World Organisation for Animal Health (OIE), said no evidence of any such genetic shift had emerged.

"We have never seen a virus which has been so stable for so long. Compared to other viruses, it is extremely stable, which minimises the risk of mutation" into a pandemic strain, he told reporters.

Vallat said a system to beef up veterinary surveillance, especially in poor countries, had borne fruit, enabling outbreaks of H5N1 in poultry flocks to be identified and swiftly eradicated.

"It took two years for our voice to be heard," Vallat said. "If we had been heard before, the virus would have been stopped in its tracks."

Vallat said, though, "there are three countries, Indonesia, Egypt and to a lesser degree Nigeria, where the disease is endemic, and this creates reservoirs from which it can bounce back."

"If we could eradicate the virus in those countries, the problem of a pandemic from Asian H5N1 would be resolved," said Vallat.

The H5N1 virus is lethal and extremely contagious among birds. It is also dangerous for humans who are in close proximity to sick poultry, who can pick up the virus through nasal droplets or faeces.

H5N1 has killed 216 people since 2003, principally in Asia, according to the latest toll posted by the World Health Organisation (WHO). Hundreds of millions of chickens, ducks and geese have died from the virus or been culled as a preventative measure.

In other comments, Vallat said that climate change, combined with the acceleration of cross-border trade under globalisation, was posing a growing threat to animal health, which in turn raised a challenge for human health.

He pointed to mosquito-borne diseases such as West Nile virus, which has become established in North America, and Rift Valley fever, which is edging northwards in Africa "and could quite easily become established in the Mediterranean."

In other comments, Vallat said the OIE was in talks with Beijing over opening a reference laboratory -- an internationally validated lab for checking samples -- in China as part of the global surveillance network for monitoring animal health.

At present, the only OIE-accredited reference labs in Asia are in Japan, but the agency is pushing hard to have these vital facilities much closer to the outbreaks of disease.

China's participation in the 172-member OIE had been dogged for 15 years over the participation of Taiwan, but the row was resolved last May.

Three Chinese labs have been put forward as reference facilities, Vallat said.

Vallat said that consumption of meat would probably rise by 50 percent by 2020 to respond to the needs of the burgeoning middle classes in Asia, and this required stronger veterinary safeguards to prevent further health scares.

http://afp.google.com/article/ALeqM5jpPvXJJ3VTHifJCBo7w3zW8DCzsQ

In related news, pigs were seen flying alongside migratory wildfowl; billions of chickens worldwide began clucking in gratitude; and mute swans in England were actually heard talking with cockney accents.

I don't know how often the OIE talks with the UN's FAO and WHO.  But judging from Monsieur Vallat's comments, they apparently don't talk enough.  Risk communication as it relates to pandemic preparedness is a tricky thing.  But the experts all agree that transparency and consistency are two extremely important concepts to adhere to.  For a leader of a global organization to make summary statements about the virulence and pandemic potential of a virus without first double-checking his data is reckless and not befitting someone of his stature.

The damage Monsieur Vallat's comments has caused to the pandemic preparedness effort worldwide cannot yet be calculated.  Perhaps the damage can be assessed later, in terms of lost human lives and poultry.  But for now, we are left with a sense of bewilderment and, quite honestly, some sense of betrayal.

Let's look at Vallat's quote again:

"We have never seen a virus which has been so stable for so long. Compared to other viruses, it is extremely stable, which minimises the risk of mutation" into a pandemic strain, he told reporters.

I have always been told that H5N1 is a mutating fool of a virus.  In four years, four distinct clades have emerged, with many subclades and mutations in abundance.  How any expert can call any influenza A virus "exceptionally stable" is beyond my comprehension, let alone H5N1. 

I have asked my expert friends for comment.  I will post them when they are available.  And it is important for the WHO and FAO to answer Vallat's comments, lest their entire bird flu eradication effort unravels.  So too, our combined efforts at preparing our leaders and decision-makers for a pandemic.  It is time to answer, and answer in unison.  But the scientists and the policy makers must pick up the gauntlet thrown down by the comments of one Monsieur Bernard Vallat.

By the way:  Judging from the abundance of photos of Monsieur Vallat on the OIE Website, it can be determined that the most dangerous airspace in all Paris is the distance between Vallat and a camera lens.

Dorset, England, is a busy place today.  Several mute swans were found dead in a nature preserve there, and they have tested positive for highly pathogenic H5N1.

Dorset is in southern England, specifically located adjacent to the English Channel and across from continental Europe.  The swans in question are indeed wild (they keep the neighbours up all night, apparently, and have wild parties).  But they are NOT migratory, which means someone -- a party crashing duck or other migratory bird, apparently -- brought the virus into the preserve and the "swannery."

Authorities will not attempt to cull the wild birds, fearing they will fly away and deposit high-path H5N1 elsewhere.  So they will test, place a cordon along the preserve, and try to contain.

The story and photo are from Guardian Unlimited.  Here goes:

http://www.guardian.co.uk/birdflu/story/0,,2238598,00.html

I have just finished reading the MIT study on the relationship between different-shaped receptors in human respiratory cells and H5N1, and all I can offer is the Monty Python rejoinder:

"My brain hurts!  My brain hurts......"

But here we go, anyway.  I will put this as simply as I can.  First, some background: We take as gospel the prevailing theory that all influenza A viruses originated within the intestinal tracts of wild birds, and are carried by migratory wildfowl.  It is theorized that influenza A started attacking humans back when the Chinese domesticated ducks a few thousand years ago.  You know, the old "Poultry, pigs and people" mantra.  We also know for certain that the cell receptor of wild bird intestines is of the type scientists call alpha 2-3.  The shape is somewhat elongated, like a cone. A cell receptor is a kind of landing strip for viruses.  The conventional description used in most media reports is a lock.  Whatever the metaphor, it involves joining the host cell with the invading cell. 

By the way, the same basic alpha 2-3 receptor is also found in the lungs of humans.  Most cases of H5N1 infection were attributed (very accurately, as it turns out) that the virus had a love-in with those alpha 2-3 receptors and the virus settled deep in the lungs of people, which also explains why the antiviral inhalant Relenza is basically worthless against the current strains of H5N1, except possibly as a precautionary measure.  The medicine cannot penetrate the crap in victims' lungs to get the antiviral medicine down there.  So swallowing Tamiflu is better than trying to inhale Relenza.

Somewhere along the way, influenza A viruses of the subtype H1, H2 and H3 grew away from this alpha 2-3 receptor and their hemagglutinin began to favor the alpha 2-6 receptors of human nasal passages and throats.  The theory was that as the virus mutated to infect people more easily, this had to do with a simple change that would make the 2-3 receptor less appealing and the 2-6 receptor more enticing, especially since it was so much easier to transmit via the nose and throat than the lungs. 

But as Lee Corso would say, "Not so fast, my friend!"  An intrepid bunch of researchers at MIT have found something a little more sophisticated than all that.  You see, the conventional theory has failed a few times in previous years.  We all know that ferrets mimic the nasal and throat capabilities of humans, so ferrets are used routinely in experiments.  We also have read about tests where high-path flu has killed humans, but ferrets keep plugging along.  Indeed, the study references this in the first page, talking about the maddening experiments where some highly pathogenic influenza A viruses -- including derivatives of the 1918 pandemic strain -- would infect some ferrets, while other subtypes known to be deadly to humans would do nothing to the fuzzy little creatures.

May I also remind everyone that the CDC's own attempts to create a pandemic H5N1 virus failed to produce infection in ferrets.  Therefore, the CDC proclaimed, it was going to be much, much harder to produce a reassortant H5N1.  As a reminder, here is the link to the CDC report (which the new report also references):  http://www.pnas.org/cgi/content/abstract/0605134103v1 .

Now, MIT has given us an important road map to analyze the pandemic potential of any avian flu.  It is not as cut-and-dried to say the virus needs to adapt to alpha 2-6 receptors.  You see, H5N1 has apparently always had the ability to infect those upper tract tissues!  That, according to the MIT study, has more to do with the viral load than any other single factor.  MIT says that there are actually two different types of alpha 2-6 receptors in humans: those little cone-shaped doobers, plus some that are umbrella-shaped ( I think they look more like a mushroom cap, but what do I know?). 

The key to human-to-human sustained transmissibility is therefore NOT a simple matter of moving from alpha 2-3 to alpha 2-6.  It is the move from cone-shaped 2-6 to umbrella-shaped 2-6 receptors.  So if the virus can, indeed, infect humans via the nose and throat cone-shaped alpha 2-6 receptors, we can attribute that to an overwhelmingly devastating whiff of the virus.  A huge viral load. 

But if H5N1 is to really, really cause a mess, it has to change its affinity from cones to umbrellas/mushrooms.  And that, says MIT, is what people need to look for now:  A change in geometry, not simply an amino acid change.  So we need to think in three dimensions, not two. 

To paraphrase my buddy Shakespeare (why I return to Hamlet is unknown to me): Aye, there's the rub: The samples the scientists used were from 1997 and 2004, respectively.  They then data-mined the results against other H5N1 substrains.  Nowhere in the report does it indicate they matched this against data on Qinghai or Fujian strains of H5N1, nor Clade 2.1 Indonesian H5N1.  maybe they did and maybe they didn't.  That, apparently, is for the world's scientists to get busy with.

A good place to start looking for that new alpha 2-6 umbrella affinity would be China.  The WHO has admitted that human-to-human transmission was probably responsible for the hospitalization of a father, whose son died of confirmed H5N1 last month. 

Man in China got bird flu from contact with infected son: officials

BEIJING (AFP) — A man in China contracted bird flu because he was in close contact with his infected son, although the virus had not mutated into a form that is highly contagious among humans, authorities said Thursday.

A 52-year-old man, identified only by his surname Lu, was hospitalised with the potentially deadly H5N1 strain of the virus soon after his son died from it on December 2. Lu has since recovered.

Chinese health ministry spokesman Mao Qunan said Lu's infection was due to close contact with his son, but that the transmission was not technically "human-to-human".

"It has no biological features for human-to-human transmission," he told journalists.

Like many human cases of bird flu in China, authorities have not been able to identify the source as neither Lu nor his son had close contact with sick or dead poultry prior to infection, he said.

He refused to elaborate on the findings, which was reached by the ministry's expert group on bird flu.

Human-to-human transmission of bird flu remains rare, but experts fear such routes of infection could cause a global pandemic if the virus mutates with each person it infects and becomes more adaptable to humans.

The World Health Organisation (WHO) said Thursday that human-to-human transmission of bird flu in the case of Lu was possible but said it had not mutated into a highly contagious form.

"A human-to-human transmission through close contact between the son and the father cannot be ruled out in this family cluster," Hans Troedsson, the WHO representative in China, told AFP. (bold mine)

"However, the biological findings at this stage show that the virus has not mutated to a form that can be transmitted from human to human efficiently."

Bird flu has so far infected at least 27 people in China, 17 of whom have died.

http://afp.google.com/article/ALeqM5gTYR7isTn-MX_ok9VfTkZ_TVOm_Q: 

Maybe, in light of this discovery, CDC should reassess the success or failure of its own experiments.  And authorities need to be very careful about making proclamations that the virus has not yet mutated, unless the samples meet this new "umbrella" test.  Now how easy or hard is it to conduct this test?  I leave that for others to answer.  My brain hurts too much for me to start looking again.

(Map from Laidback Al above).

It is extremely difficult to try and nail down what is happening in Egypt right now.  But from all accounts, and from reading a multitude of postings on flu sites, the best description I can come up with is:  Sheer bedlam.

The last time I looked into the ongoing and escalating situation in the upper Nile delta, the number of suspected cases was at 102, with 5 confirmed human H5N1 infections and four deaths (see earlier blog).Now, it is believed that at least 25 people per day are being admitted with bird flu symptoms, and the Egyptian government has begun exterminating tens of thousands of birds, banned the sale of live poultry, and are at least debating the mass slaughter of pigs.  This would seem to underscore a growing concern in Egypt that pigs have become a reservoir of H5N1, or could become the fabled "mixing vessel" that produces the reassortant Pandemic Strain of H5N1.  Or it could be that the Egyptian government is considering the adoption of a South Korean-esque methodology toward H5N1 eradication.  The South Korean protocol is now to kill every single non human living creature within a 1-3 kilometer radius of an H5N1 source infection.  Every dog, cat, horse, goat, bird, pig, you name it, it's dead -- except for homo sapiens.

All this activity would be cause enough for concern, with one important new development:  The evidence of numerous suspected H5N1 family clusters emerging in familiar locations throughout the nation. We also know that seasonal flu is raging across Egypt.  That should scare us almost as much as if all these current suspected H5N1 cases tested positive (they won't all test positive).  That is because every single case of human H5N1 is now, especially, a potential case of reassortment and the instantaneous production of H5N1 that is adapted to humans.

One look at the lastest Google map, maintained by Dr. Henry Niman, underscores that concern. Go ahead and open a new browser window and follow along.  The map can be found by clicking here: http://maps.google.com/maps/ms?ie=UTF8&hl=en&msa=0&msid=106484775090296685271.000442accf347f22ad5d4&t=h&om=0&ll=30.145127,31.398926&spn=3.932693,6.130371&z=7

While there are still only 5 confirmed cases of human H5N1 infection (color blue), look at how close those cases are to other suspected H5N1 cases.  Now even if those suspected cases test negative for bird flu, their close physical proximity to actual confirmed H5N1 flu cases is unsettling.  And the disclosure that some people who are testing negative for H5N1 are still being held for observation shows that there are some who may not completely trust the accuracy of the tests, and may elect to place caution at the front of the queue.  Good for them!

The fact that pigs are showing up as an area of concern in a multitude of machine-translated missives from the Egyptian government and media should warn us that they are genuinely concerned about the potential for a reassortant H5N1 to emerge from swine.  As we all know, human and avian flus can reassort, or exchange their genes, via pigs.  Pigs acting as the "mixing vessel" is a theory that has been proven as close to cold hard fact as one can get in the year 2008.  The latest St. Jude/Iowa State/U. of Minnesota study should do away with any lingering misgivings about the theory of reassortment.

An interesting post from new Egyptian blogger Zeinobia and her Egyptian Chronicles, located at: http://egyptianchronicles.blogspot.com/2008/01/forget-about-bird-flu-now-it-is-pig-flu.html, also talks about the pig industry in Egypt and how local government decisions to exterminate pigs have been overruled by the farm lobby.  By the way, any independent-thinking Egyptian blogger/ette is a wonderful thing.  Freedom of speech (at least for the moment) over there is good.

This emerging situation in Egypt deserves close scrutiny.