Gripe aviar

Micrografía electrónica de transmisión coloreada de partículas del virus H5N1 de la gripe aviar. Foto: NIAID (Wikimedia Commons / CC BY 2.0).

InternacionalSalud Pública, ,

De forma sorprendente, una epidemia de gripe aviar por el virus influenza A(H5N1), iniciada en 2020, afectó a vacas lecheras de varios estados de EEUU en marzo de 2024. Es la primera vez que esto sucede. Ha habido al menos cuatro casos de infecciones leves (habitualmente conjuntivitis) en personas en contacto con vacas infectadas.

Un cambio genético del virus A(H5N1) circulante, que es del subgrupo 2.3.4.4b, ha facilitado su adaptación a los mamíferos. El H5N1 está en la lista de virus potencialmente emergentes desde hace 20 años. Ha causado unos 900 casos humanos en 23 países, con una letalidad del 50%.…  Seguir leyendo »

Samples are taken from a dead sea lion in the Paracas National Reserve, in Peru, where many have died of the H5N1 bird flu virus this year. Photograph: SERNANP/AFP/Getty Images

InternacionalSalud Pública, ,

Last month a pet dog in Canada died of H5N1, also known as bird flu, after eating a wild goose. Worryingly this follows a pattern, with an increasing number of bird flu cases appearing in mammals who come into contact with an infected bird, dead or alive.

When you see a wild bird such as a duck or seagull, think bird flu. Because it’s actually more likely than not they’re infected with the virus. And many species of wild birds are asymptomatic, meaning that they don’t show any symptoms. The risk of transmission to pets is low, but they can get sick from chewing or eating an infected bird, whether it’s dead or alive.…  Seguir leyendo »

In an area affected by the bird flu off the coast of Perros-Guirec, France, September 2022. Stephane Mahe / Reuters

InternacionalSalud Pública,

In 2005, U.S. President George W. Bush stood at a lectern in Bethesda, Maryland, to make an important announcement. He was joined by five members of his cabinet, two senators, three congressmen, and multiple international guests. It was an unusual show of force for a press conference, and with two unpopular wars underway and the response to Hurricane Katrina still floundering, there was plenty else to attend to.

“Leaders at every level of government have a responsibility to confront dangers before they appear and engage the American people on the best course of action”, he declared. A failure to do so, he said, could cost millions of lives and trillions of dollars.…  Seguir leyendo »

Un pelícano que se sospecha murió a causa de la influenza aviar H5N1 en una playa de Perú en diciembre. Ernesto Benavides/Agence France-Presse vía Getty Images

InternacionalSalud Pública, ,  

Mientras el mundo apenas está comenzando a recuperarse de los estragos de la COVID-19, ya se enfrenta a una posible pandemia provocada por un patógeno mucho más mortífero.

Desde hace mucho tiempo, la gripe aviar —llamada más formalmente influenza aviar—ha estado atemorizando a los científicos. Este patógeno, sobre todo la cepa H5N1, no ha infectado con frecuencia a los seres humanos, pero cuando lo ha hecho, ha causado la muerte del 56 por ciento de quienes se sabe que la han contraído. No ha generado una pandemia gracias a la poca capacidad que tiene de pasar con facilidad de una persona a otra, si es que lo hace.…  Seguir leyendo »

A pelican suspected to have died from H5N1 avian influenza on a beach in Peru in December. Ernesto Benavides/Agence France-Presse — Getty Images

InternacionalSalud Pública, ,

As the world is just beginning to recover from the devastation of Covid-19, it is facing the possibility of a pandemic of a far more deadly pathogen.

Bird flu — known more formally as avian influenza — has long hovered on the horizons of scientists’ fears. This pathogen, especially the H5N1 strain, hasn’t often infected humans, but when it has, 56 percent of those known to have contracted it have died. Its inability to spread easily, if at all, from one person to another has kept it from causing a pandemic.

But things are changing. The virus, which has long caused outbreaks among poultry, is infecting more and more migratory birds, allowing it to spread more widely, even to various mammals, raising the risk that a new variant could spread to and among people.…  Seguir leyendo »

An employee gives out hand sanitizer to a girl in Zhongshan Park on Tuesday in Wuhan, China. (Getty Images)

MundoAsia, , , ,

The H5N1 avian influenza outbreak in 1996, severe acute respiratory syndrome (SARS) in 2003-2004 and now covid-19 were all first detected in China. Some accounts even claim that a precursor to the 1918 influenza pandemic, the worst in modern history, first appeared in China.

Why do so many highly infectious diseases appear to start their deadly spread in China?

Many recent articles have honed in on the policy errors of China’s authoritarian political system. As the novel coronavirus began to sweep across the United States, President Trump sought to directly implicate Beijing by referring to “the Chinese virus,” instead of its technical designation, SARS-COV-2.…  Seguir leyendo »

MundoAsia, , ,

How does the Chinese Communist Party manage to calm a public convinced that -- on matters of public health, at least -- officials are probably lying to them?

It’s a critical question as infections and fatalities related to the H7N9 bird flu slowly tick upward, unnerving Chinese disinclined to trust their government. The crisis of confidence has its roots in the fatal consequences of the high- level coverup of SARS in 2003, and, more recently, in the still unexplained dead-pig tide that polluted Shanghai waterways. With this sorry history as a precursor and widely assumed precedent, Chinese seem ready to believe anything that doesn’t come from a government mouthpiece -- especially if it contradicts the official story or fills a knowledge gap that the government hasn’t addressed.…  Seguir leyendo »

InternacionalSalud Pública, , ,

News that a new form of deadly bird flu recently killed two Shanghai residents arrived in the morning’s papers, along with some expert suggestions on how to avoid catching the unwelcome disease.

“Wash your hands, and cover your nose and mouth when coughing or sneezing,” was the advice published in the Oriental Morning Post, Shanghai’s most popular newspaper (and repeated in others). “And avoid eating or contact with dead and diseased livestock.”

That last directive might be a little tricky to fulfill. Since early March, Shanghai’s waterways have been clogged by dead pigs -- officially at least 11,000 of them but likely a lot more.…  Seguir leyendo »

InternacionalSalud Pública, ,

H5N1 bird flu has caused serious disease and deaths in humans. More than half of the almost 600 patients have died. The virus has not, however, sparked off an influenza pandemic as it cannot spread efficiently from human to human. Research supervised by Ron Fouchier, a fellow virologist in the laboratory that I head at Erasmus Medical Centre in Rotterdam, has shown that only a handful of mutations would allow the virus to spread efficiently among mammals. Similar experiments carried out by a US-Japanese group have yielded largely the same data.

These experiments seem to have rekindled the debate that has smoldered since the last bio-terrorist attacks took place in the US more than a decade ago.…  Seguir leyendo »

InternacionalSalud Pública, ,

If you were paying attention to the flap over two recent flu experiments involving ferrets, you may have come away with the impression that scientists all but waved a red flag in front of terrorists and said, "Here's a perfect biological weapon — help yourselves."

But there's really not much cause for alarm.

Here's the background. In December, the National Science Advisory Board for Biosecurity asked the premier science journals Science and Nature to redact key information from two papers scheduled for publication, one by University of Wisconsin virologist Yoshihiro Kawaoka and the other by a team at Erasmus Medical Center in Rotterdam, the Netherlands, led by Ron Fouchier.…  Seguir leyendo »

InternacionalSalud Pública, ,

Adeadly influenza virus has circulated widely in birds in recent years, decimating flocks but rarely spreading to humans. Nonetheless, because of its persistence in bird flocks, this highly pathogenic virus has loomed as a major public health threat. Seasonal influenza kills less than 1 percent of the people it infects. In contrast, human infections with the H5N1 virus, though exceedingly rare, are fatal in most cases. Should this virus mutate in a way that allows it to be transmitted as efficiently among people as seasonal influenza viruses are, it could take an unprecedented toll on human life.

A number of important scientific and public health questions regarding this virus remain unanswered, including the likelihood of such mutations arising and the mechanisms by which they may occur.…  Seguir leyendo »

InternacionalSalud Pública, , ,

Here's a concept you've probably never heard of: "viral sovereignty." This extremely dangerous idea comes to us courtesy of Indonesia's minister of health, Siti Fadilah Supari, who asserts that deadly viruses are the sovereign property of individual nations -- even though they cross borders and could pose a pandemic threat to all the peoples of the world. So far "viral sovereignty" has been noted almost exclusively by health experts. Political leaders around the world should take note -- and take very strong action.

The vast majority of repeated avian flu outbreaks the past four years, in both humans and poultry, have occurred in Indonesia.…  Seguir leyendo »

InternacionalSalud Pública, ,

Bird flu has not yet turned into a pandemic, but it is already killing the meager hopes of some of the world’s poorest people for a marginally better life.

When poultry become infected with the deadly strain of avian influenza (H5N1), it is essential that all birds nearby be culled to prevent further spread. We all stand to benefit from this important pandemic prevention strategy, recommended by the World Health Organization and the United Nations Food and Agriculture Organization. Unfortunately, however, the world’s poor are unfairly shouldering the burden of the intervention.

Last month officials in Jakarta, Indonesia, announced a ban on household farming of poultry there.…  Seguir leyendo »

InternacionalSalud Pública, ,

Just when most of us thought it was safe to go back into the water (or at least eat chicken and turkey), H5N1 raises its black dorsal fin and reminds us that it has unfinished business with the human race. Although hypotheses abound, virologists have yet to understand avian flu's enigmatic behaviour: burning like a wildfire one season, going to ground the next. However, since the original outbreak in Hong Kong in 1997, one trend remains consistent: after each hibernation or disappearance, H5N1 re-emerges with its virulence intact and its geographical and species ranges extended.

A decade of breakneck research, driven by the fear that another 1918 influenza catastrophe (50-100 million dead in three months, the most murderous event in human history) was close at hand, has provided little solace.…  Seguir leyendo »

InternacionalSalud Pública, ,

By Johnjoe McFadden, a professor of molecular genetics at the University of Surrey and author of Quantum Evolution (THE GUARDIAN, 13/04/06):

Creationists often claim that evolution is just a theory since no one has ever observed it. Being generally a slow process, it is hard to catch evolution in action. But it isn't always slow. For fast replicating pathogens, such as the bird flu virus, evolutionary change can be rapid and lethal. Even Darwin, the originator of the theory of natural selection, lamented the "clumsy, wasteful, blundering, low and horribly cruel" nature of its action. The evolution of the H5N1 strain of bird flu is now advancing on a million wings, and its course may seal the fate of many of us.…  Seguir leyendo »

EuropaUnión Europea, , ,

By Magnus Linklater (THE TIMES, 12/04/06):

The dead swan has been safely tucked away in the laboratory’s deep freeze. The scare story has retreated to the inside pages. The Government’s chief scientist pronounces himself happy with the way the outbreak has been handled. There is really nothing much left to trouble us, it seems, about this avian flu business — save for the tell-tale whiff of complacency hanging in the air.

The way that the Government and the poultry industry responded to the discovery of an H5N1-infected bird in Scotland was, by all accounts, calm and professional; the precautions taken were swift and exemplary.…  Seguir leyendo »

InternacionalSalud Pública, ,

By Jackie Ashley (THE GUARDIAN, 10/04/06):

There has been panic in Scotland, with an estimated 45,000 masks bought within days of the first reports of the possible pandemic, and calls for anyone with flu-like symptoms to be detained. This, though, was three years ago, when the coming plague was Sars, an infection we were told might sweep the world as it emerged from China and Vietnam. There, it is true, several hundred people eventually died; the toll in Britain, and indeed Scotland, was zero.

So we have been here before. When we read of emergency food plans to tackle shortages, of school closures to cut the likely death toll among children and of even grimmer contingency plans for mass graves for up to 320,000 people who might die from bird flu, then we all need to pinch ourselves and remember the earlier waves of media-fanned panic.…  Seguir leyendo »

ReflexionesNaturaleza, ,

By Marc Siegel an associate professor at the New York University School of Medicine and the author of "Bird Flu: Everything You Need to Know About the Next Pandemic."

Fear is a deeply rooted emotion -- one that can serve as a lifesaving response to imminent danger. But because we humans often magnify risk, fear can also cause us to overreact to remote threats, such as bird flu.

According to a significant study published in the prestigious British journal Nature recently, the H5N1 bird flu virus is at least two large mutations and two small mutations away from being the next human pandemic virus.…  Seguir leyendo »

Pandemias: ¿un riego para la seguridad?

EspañaSanidad y Salud Pública, ,

Por Rickard Sandell. Investigador Principal para Demografía y Población, Real Instituto Elcano (REAL INSTITUTO ELCANO, 15/03/06):

Tema: Este análisis estudia los escenarios de riesgo a los que podría enfrentarse España en el caso no demasiado improbable de que el país se vea afectado en el futuro por una pandemia de gripe humana.

Resumen: Hoy por hoy la posibilidad de que se produzca una pandemia de gripe humana es poco más que teórica. No obstante, y debido a la propagación de la gripe aviar y al hecho de que se han producido casos de transmisión de aves a humanos, la OMS ha emitido una alerta de pandemia para informar de que un nuevo subtipo de virus de la gripe está afectando a seres humanos, aunque de momento no se está extendiendo de forma eficaz y sostenible entre la población humana.…  Seguir leyendo »

MundoÁfrica, ,

Par Patrice Debré, président du Centre de coopération internationale en recherche agronomique pour le développement (Cirad), professeur d'immunologie à la Pitié-Salpêtrière, et Emmanuel Camus, directeur du département élevage et médecine vétérinaire du Cirad (LE FIGARO, 03/03/06):

Avant de devenir peut-être, à un terme inconnu, la pandémie (maladie humaine largement répandue) redoutée par certains, la grippe aviaire est d'abord une épizootie, maladie animale qui très exceptionnellement affecte l'homme (moins de 100 victimes humaines depuis le début de la crise). Les conséquences économiques de cette maladie animale déjà présente pourraient être graves en Europe. Cependant, l'Europe et la France en particulier disposent d'armes pour la contrôler : des services vétérinaires et des laboratoires efficaces, des réseaux de surveillance présents sur le terrain, des éleveurs bien formés et bien informés...…  Seguir leyendo »