Pigs in Cameroon infected by humans, researchers say.

Pigs in village, Cameroon

UCLA life scientists and their colleagues have discovered the first evidence of the H1N1 virus in animals in Africa. In one village in northern Cameroon, a staggering 89 percent of the pigs studied had been exposed to the H1N1 virus, commonly known as the swine flu.

“I was amazed that virtually every pig in this village was exposed,” said Thomas B. Smith, director of UCLA’s Center for Tropical Research and the senior author of the research. “Africa is ground zero for a new pandemic. Many people are in poor health there, and disease can spread very rapidly without authorities knowing about it.”

H1N1 triggered a human pandemic in the spring of 2009, infecting people in more than 200 countries. In the U.S., it led to an estimated 60 million illnesses, 270,000 hospitalizations and 12,500 deaths, according to the Centers for Disease Control. The virus, known scientifically as Influenza A (H1N1), is made up of genetic elements of swine, avian and human influenza viruses. The pigs in Cameroon, the researchers say, were infected by humans.

“The pigs were running wild in that area,” said lead author Kevin Njabo, a researcher in UCLA’s department of ecology and evolutionary biology and associate director of the Center for Tropical Research. “I was shocked when we found out it was H1N1. Any virus in any part of the world can reach another continent within days by air travel. We need to understand where viruses originate and how they spread, so we can destroy a deadly virus before it spreads. We have to be prepared for a pandemic, but so many countries are not well-prepared — not even the United States.”

Njabo and his colleagues randomly collected nasal swabs and blood samples from domestic pigs that were part of 11 herds in villages and farms in Cameroon in 2009 and 2010. The results are published in the current issue of Veterinary Microbiology, a peer-reviewed scientific journal specializing in microbial animal diseases.

Nasal swabs can detect a current infection, and blood samples reveal past exposure to a virus. Because an active infection lasts only about five days, “we have to be lucky to get an active infection in the field, but evidence of the infection stays in the blood.”

In the village in northern Cameroon, Njabo found two pigs with active H1N1 infections, and virtually every other pig had evidence of a past infection in its blood.

“The pigs got H1N1 from humans,” Njabo said. “The fact that pigs in Africa are infected with the H1N1 flu virus illustrates the remarkable interconnectedness of the modern world with respect to diseases. The H1N1 virus that we found in livestock in Cameroon is virtually identical to a virus found in people in San Diego just a year earlier, providing an astonishing example of how quickly the flu can spread all over the globe.

“The discovery of H1N1 in African swine is also important because it shows how farming practices can trigger disease outbreaks and suggests opportunities for improving human and livestock health. Our studies indicate that H1N1 infections are more common in swine that wander freely in villages than in animals that are confined to farms.”

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Most clinical trials for treating stroke have focused on adults.

James Tatum, UC San Francisco

Last year a 4-year-old arrived at UCSF Medical Center from the emergency room of another hospital with pneumonia — and worse. Infected with H1N1 influenza virus, the child had developed a blood clot.

The clot had dislodged and gotten stuck in one of the big vessels supplying much of the oxygen-rich blood to the child’s brain. It was a stroke, and if the UCSF medical team had not responded in time, the child could have died.

The lessons of that day are part of a new retrospective study by interventional neuroradiologist, James Tatum, M.D., and colleagues at UCSF looking at the effectiveness of treating children having stokes with a technique known as “mechanical embolectomy,” a standard treatment for stroke in adults.

“Mechanical embolectomy holds promise as a first-line therapy for large vessel acute ischemic stroke in children,” said Tatum, who presented the work this week at the 63rd Annual Meeting of the American Academy of Neurology in Hawaii. However, he added, “larger studies are going to have to be performed in order to investigate.”

The study looked at four children treated for stroke at UCSF in the last few years using two devices approved by the U.S. Food and Drug Administration.

One, the Merci manufactured by Concentric Medical Inc. in Mountain View, is a corkscrew of sorts that surgeons thread through the blockage and then pull out to remove the obstruction. The other device, called the Penumbra System and manufactured by Penumbra Inc. in Alameda, is a tube with a plunger that creates suction and aspirates the clot away.

Typically these mechanical devices are combined with a clot-busting compound like tPA, which breaks up the molecules gluing the clot together and helps clear the artery.

In the four cases described in the study, both devices performed well, Tatum said. Neither Tatum nor UCSF has any financial interest in either device.

Even though there were only four children in the study, it was something of a milestone because it nonetheless was the largest group of children ever studied for this new type of stroke treatment. Even though stroke is one of the leading causes of death in adults, it is relatively rare in children. All the large clinical trials for treating stroke have focused on adults.

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Flu activity usually peaks in January, February or March.

Tan Nguyen, UC Davis

By Tan Nguyen, M.D.

Despite the recent warm spell and other early signs of spring, it’s important to remain vigilant about influenza prevention.

While the infectious disease typically gets lots of media attention in the fall thanks to the introduction of seasonal vaccines, flu activity itself usually peaks in January, February or March.

And as of mid-February, the California Department of Public Health reports that overall influenza activity is on the increase. Cases are now present in both Southern California and Northern California.

To help keep from falling victim, pay attention to prevention behaviors such as handwashing and covering coughs and sneezes. And if you haven’t been already, consider getting vaccinated.

The flu, or influenza, is a viral illness that causes fevers, chills, sweats, headache, and muscle aches.  It can also lead to fatigue, a painful cough, sore throat, and sinus and chest congestion.

While influenza symptoms can last from several days to a couple of weeks, most people start to gradually get better after two or three days. However, in some high-risk groups of people, severe symptoms can develop.

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New study aims to offer more solid evidence of vaccine safety in pregnancy.

Christina Chambers, UC San Diego

The Organization of Teratology Information Specialists (OTIS), a nonprofit organization based at UC San Diego, with affiliates across North America, urges pregnant women to receive the influenza vaccine as soon as possible. The recommendation comes shortly after the American College of Obstetricians and Gynecologists Committee on Obstetric Practice issued new guidelines regarding the influenza vaccine during pregnancy.

OTIS aims to educate women about exposures during pregnancy and lactation through a toll-free hotline as well as observational research studies. The organization is looking for the help of pregnant women to collect information on exposures such as the flu vaccine in pregnancy, with a goal to enroll 1,100 pregnant women across the U.S. in the study by March 2011.

“The newest opinion from experts is that pregnant women at any gestational age during the flu season should receive the influenza vaccine,” said Christina Chambers, Ph.D., MPH, UC San Diego professor of pediatrics and an epidemiologist with a special focus in the area of birth defects prevention. Chambers also serves as program director of OTIS’ California affiliate and the California Teratogen Information Service (CTIS) Pregnancy Health Information Line.

“It’s preferable for a woman to receive the immunization early during the flu season since protection against the flu doesn’t begin to set in until about two weeks after the flu shot is administered,” Chambers added. The vaccine protection typically lasts six to eight months.

According to Chambers, fewer than half of pregnant women get the flu vaccine while they are pregnant, even though the recommendation is that all pregnant women receive the vaccine. She adds that pregnant women have an increased risk of having serious complications from the flu, such as severe breathing problems. Severe disease and even death from infection with the flu virus occurs more often in pregnant women than in women who are not pregnant.

The flu vaccine being administered during the 2010-11 flu season provides protection against both the seasonal and H1N1 flu viruses. Unlike last season, this year a separate H1N1 flu shot is no longer needed. In addition to the flu shot, a nasal-spray influenza vaccine is also available. However, unlike the flu shot, the nasal-spray vaccine contains a live, but weakened virus, so is not recommended during pregnancy.

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Viruses love plane travel. They get to fly around the world inside a closed container while their infected carrier breathes and coughs, spreading pathogens to other passengers, either by direct contact or through the air. And once people deplane, the virus can spread to other geographical areas.

Scientists already know that smallpox, measles, tuberculosis, seasonal influenza and severe acute respiratory syndrome (SARS) can be transmitted during commercial flights. Now, in the first study to predict the number of H1N1 flu infections that could occur during a flight, UCLA researchers found that transmission during transcontinental travel could be fairly high.

Reporting in the current online edition of the journal BMC Medicine, Sally Blower, director of the Center for Biomedical Modeling at the Semel Institute for Neuroscience and Human Behavior at UCLA, along with Bradley Wagner and Brian Coburn, postdoctoral fellows in Blower’s research group, used novel mathematical modeling techniques to predict in-flight transmission of the H1N1 virus.

They found that transmission could be rather significant, particularly during long flights, if the infected individual travels in economy class. Specifically, two to five infections could occur during a five-hour flight, five to 10 during an 11-hour flight, and seven to 17 during a 17-hour flight.

“Clearly, it was air travel, by transporting infectious individuals from the epicenter in Mexico to other geographic locations, that significantly affected the spread of H1N1 during the outbreak last spring,” Coburn said. “However, until our study, it hadn’t been determined how important in-flight transmission could be. Therefore, we decided to make a mathematical model and predict what could be expected to occur during a flight.”

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School faculty at the California Animal Health and Food Safety Laboratory System have confirmed that a captive cheetah from California tested positive on preliminary tests for the pandemic H1N1 virus.

This is the first non-domestic cat to be diagnosed with the pandemic H1N1 influenza virus.  Dr. Beate Crossley, a virologist, made the diagnosis. The diagnosis was made using a nasal swab taken from the cheetah where it lives and sending the specimen to the laboratory in Davis at the School of Veterinary Medicine.

The animal has since recovered, and animals and people that have been in contact with the cheetah show no symptoms of the disease.

It is not known how the cheetah contracted the virus.

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The 2009 H1N1 influenza virus used a new strategy to cross from birds into humans, a warning that it has more than one trick up its sleeve to jump the species barrier and become virulent.

In a report in this week’s early online edition of the journal Proceedings of the National Academy of Sciences, UC Berkeley researchers show that the H1N1, or swine flu, virus adopted a new mutation in one of its genes distinct from the mutations found in previous flu viruses, including those responsible for the Spanish influenza pandemic of 1918, the “Asian” flu pandemic in 1957 and the “Hong Kong” pandemic of 1968.

Previous influenza strains that crossed from birds into people had a specific point mutation in the bird virus’s polymerase gene that allowed the protein to operate efficiently inside humans as well. The polymerase transcribes the virus’s RNA, allowing the host to express viral genes, and also copies the viral genome, needed to make new viruses.

The 2009 H1N1 virus retains the bird version of the polymerase, but has a second mutation that seems to suppress the ability of human cells to prevent the bird polymerase from working.

[See additional coverage: Berkeley Lab release]

“We were quite shocked when we looked at the swine flu virus, which was clearly replicating in people and other mammalian systems, yet had a polymerase that looked like it was derived from a bird virus, which should not function too well in a human cell type,” said UC Berkeley post-doctoral fellow Andrew Mehle of the Department of Molecular and Cell Biology. “The other mutation within the polymerase seems to compensate and allow the enzyme to function.”

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Dr. Christian Sandrock of UC Davis’ Divisions of Infectious Diseases and Pulmonary and Critical Care Medicine gives an update on the H1N1 virus, including a review of prior pandemics, the virology of H1N1, the current epidemiology, diagnosis and treatment updates, as well as vaccination and planning.

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UCSF Medical Center and UCSF Children’s Hospital are implementing a temporary change to their visitor policy due to a recent increase in cases of H1N1 flu and the potential for the virus to spread.

Under the new policy, which goes into effect Monday, Nov. 9, 2009, visitors under the age of 16 will no longer be allowed on patient care floors and will be restricted to the hospitals’ cafeteria and main lobby.

“We are applying this change to our visitor policy because we have seen a modest increase in total flu cases both in our patients and in the general population,” said Joshua Adler, MD, chief medical officer of UCSF Medical Center and UCSF Children’s Hospital. “Because H1N1 is more likely to occur in children, we believe this is a prudent next step that will help reduce the risk of exposure to our patients and healthcare workers.”

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The national H1N1 flu vaccine shortage is hitting the University of California, where campuses and medical centers have scant supplies.

UC can’t purchase flu vaccine doses itself. The university and other health care providers in the state rely on local public health departments to supply them.

“The H1N1 vaccine is trickling in at best at the medical centers and it’s almost nonexistent at campuses,” said Grace Crickette, UC chief risk officer. “Our expectation is that the public health departments will give us some, but it’s going to be limited and sporadic.”

Meanwhile, Kaiser Permanente — which has about 6.6 million members in California, including almost 32,000 UC employees — does have larger amounts of H1N1 vaccine, which it is giving to high-risk groups first. Kaiser has a larger supply of H1N1 vaccine because it entered a 1998 partnership with the state Department of Public Health and the national Centers for Disease Control and Prevention to augment flu surveillance efforts. As part of Kaiser’s participation in the California Influenza Surveillance Project, that allows it greater access to flu vaccine.

Vaccine priority groups include pregnant women, children 6 months to 18 years old, young adults 19 to 24 years old, caregivers of children younger than 6 months, adults 25-64 years old with chronic health conditions and health care and emergency workers.

While UC would like to inoculate all UC employees who fit those priority groups, employees should get vaccinated outside of UC if they can, Crickette said. UC employees with Kaiser health insurance should get vaccinated there, and employees with other insurers should check with their physicians or public health departments, she said. Similarly, UC would like to offer H1N1 flu clinics for students, but due to the vaccine shortage, students should take advantage of any other opportunity to get vaccinated.

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UC Davis researchers studying the 2009 H1N1 influenza virus, formerly referred to as “swine flu,” have identified a group of immunologically important sites on the virus that are also present in seasonal flu viruses that have been circulating for years. These molecular sites appear to result in some level of immunity to the new virus in people who were exposed to the earlier influenza viruses.

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