Author Archives: Beth Mole

Standard vaccines can offer protection against H5N1 pandemic flu

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Scientists may be able to protect humans from avian influenza viruses — before they have even evolved to spread among people.

An experimental flu vaccine designed for a bird-specific H5N1 influenza virus can protect humans from a lab-made H5N1 strain engineered to pass among mammals. The finding is published today in the Journal of Clinical Investigation.

The vaccine was made the same way as seasonal flu shots. But it was tested on a synthetic H5N1 flu, tweaked to

Controversial avian influenza work yields insight into combating looming viruses. EL ALVI/FLICKR

Controversial avian influenza work yields insight into combating looming viruses.
EL ALVI/FLICKR

spread among ferrets, a model of human infection. Doing any research of this sort has been dogged by heated debate and self-imposed moratoriums.

“The transmissible viruses are very scary because H5N1 has a very high mortality rate,” says lead author James Crowe, of Vanderbilt University in Nashville, Tennessee. But he says that the study justifies creating such dangerous pathogens in lab. “Our paper shows that there is a very clear mechanism for conventional vaccines to kill these things.”

Crowe and his colleagues took the blood of four patients given the experimental vaccine, and singled out the antibodies that could attack H5N1 viruses. They next wanted to test whether these antibodies could protect against the synthetic H5N1 virus — scientist’s best estimation of what a potentially pandemic virus may look like.

But scientists had enacted a voluntary moratorium on working with the highly pathogenic strains out of fear that they could get out of the lab or be used as a weapon.

To get around this, the researchers used DNA sequences from the synthetic virus to create pseudo-versions that would not cause disease. They found that antibodies from the patients’ blood could defeat the faux transmissible flu by binding between mutations that allow it to spread among mammals.

Richard Webby, a flu expert at St Jude Children’s Research Hospital in Memphis, Tennessee, says that the finding confirms that vaccines based on the bird virus can still be useful against strains that become more infectious. “Those transmission changes didn’t really seem to affect the protection afforded by the vaccines,” he explains. Webby says that the approach could guide vaccine development for other looming avian flu viruses, such as H7N9.

But Simon Wain-Hobson, chair of the Foundation for Vaccine Research in Washington DC, is less convinced that the synthetic virus will predict exactly how a real pandemic H5N1 will behave. Moreover, he says that the artificial virus did not lead to a better vaccine, which some scientists have claimed is the point of doing research with human-transmissible viruses.

Panel supports hepatitis C screening for baby boomers

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A US government advisory panel today recommended  that individuals born between 1945 and 1965 be screened for the hepatitis C virus. The announcement, which strengthens the panel’s earlier advice, increases the likelihood that health-care payers, including Medicaid, will cover screening costs for baby boomers, and that physicians will follow the guidance.

The US Preventive Services Task Force (USPSTF), a group of health experts assembled by the US Department of Health and Human Services,  had before only weakly endorsed generational screening. In a draft recommendation released in November, the USPSTF said that screening the country’s more than 72 million baby boomers would generate a marginal net health benefit, grading the recommendation a  ‘C.’ Since many health-care payers follow only recommendations dubbed B or higher by the panel, experts were concerned that physicians would not implement hepatitis C screening for baby boomers.

But in its final statement, the USPSTF upgraded that recommendation to a B.  Acknowledging that not all people who test positive for hepatitis C will develop disease, and treatments often have significant side effects, the panel said that new studies helped make the case that generation-wide screening would be substantially beneficial.

“This is a rapidly moving field and the treatments are always advancing,” says USPSTF panel member Kirsten Bibbins-Domingo, an epidemiologist at the University of California, San Francisco.

The move aligns the USPSTF with the US Centers for Disease Control and Prevention, which in August unequivocally recommended that people  between the ages of 48 and 68 years old be tested for the blood-borne virus, which causes liver disease and cancer. Experts estimate that about 4 million people in the United States are infected with hepatitis C, and  three-quarters of those infected are members of the baby-boom generation — possibly owing to intravenous drug use or past transfusions of unscreened blood.

Overall, up to 75% of those infected with hepatitis C may be unaware of their status owing to the slow onset of diseases caused by the virus. Proponents of routine testing for US baby boomers have argued that the cheap, non-invasive screening could identify more than 800,000 new cases of hepatitis C — which could then be treated using new drugs that are highly effective at eliminating the infection.

David Thomas, a viral-hepatitis specialist at Johns Hopkins University in Baltimore, Maryland, said the USPSTF decision was “a major step forward in the public-health response to hepatitis C infection”. Regardless of what factors influenced the panel’s opinion, “the major message”, says Thomas, “is that we have everyone on board”.

Marine Biological Laboratory votes to align with University of Chicago

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Members of the Marine Biological Laboratory (MBL), a venerable but financially strapped research institute in Woods Hole, Massachusetts, voted 158 to 2 today in favour of an alliance with the University of Chicago, in Illinois.

The proposed affiliation, if approved, would shift control of the MBL to the University of Chicago.

A view of the MBL across Eel Pond FLICKR/Vince Smith

A view of the MBL across Eel Pond {credit}FLICKR/Vince Smith{/credit}

But the alignment gained widespread support as a way to brighten the 125-year-old institution’s financial outlook as well as solidify its scientific connections.

“The institution has had longstanding ties with the University,” says MBL senior scientist Jonathan Gitlin. He notes that the MBL’s  first two directors, Charles O. Whitman and Frank Lillie, were both faculty members at the University of Chicago. He described the atmosphere at the 1 June vote as jubilant, and says that the partnership “will lead to another great step in the future of the institution”.

MBL president and director Joan Ruderman proposed the affiliation last December after facing losses in contributions and investment earning, financial hardships shared by many private labs. Since 2009, the institute’s annual revenue has dropped by more than US$8 million, leaving it with $41 million in income in 2012. Meanwhile, the costs to run the lab, which employs 270 scientists and staff and hosts more than 300 visiting scholars each year, have increased. The institute’s expenses overshot its income by nearly $6 million last year.

“This affiliation is definitely intended to improve this [financial] situation,” says corporation member Garland Allen, a biologist at Washington University in St Louis, Missouri.

In a 28 January letter to the MBL community, Ruderman described the affiliation as a way to “create an improved financial foundation that will enable the MBL to meet the demands of modern science and current funding realities”.

For its part, the University of Chicago aims to use the connection to bolster its research in marine biology and conservation. In a 24 May letter to the MBL community, Neil Shubin, associate dean for academic strategy at the university, wrote that these “fields are not among the University’s existing strengths”. He went on to write that the university supported the affiliation because they “believe in the fundamental intellectual model of the MBL, despite the challenging financial environment”.

The decision to finalize the affiliation now moves to the board of trustees at each institution, both of which declined to provide a timeline for a decision, citing further negotiations.

Editor’s note: An earlier version of this blog post suggested that the MBL is controlled by its corporation members when in fact it is governed by its board of trustees.

Four main culprits found for serious childhood diarrhoea

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Just four pathogens underpin most cases of serious diarrhoea in children — the second leading killer of

Rotavirus particles
FLICKR/AJC1

young children worldwide — according to a study published today in The Lancet.

Out of nearly 40 diarrhoea-causing microbes, the researchers identified four primary culprits: rotavirus, Cryptosporidium, a toxic type of Escherichia coli, and Shigella. The winnowing of the list could allow health experts to design targeted health campaigns.

“I think what we have done is allow doctors and public health experts to prioritize and potentially save thousands of lives,” says Karen Kotloff, a paediatrician at the University of Maryland, Baltimore, and first author of the study. Diarrhoeal diseases kill an estimated 800,000 young children each year, second only to pneumonia, which kills around 1.2 million.

The 3-year study began in 2007 and involved nearly 22,000 children under the age of 5 in seven locations in sub-Saharan Africa and south Asia — making it the largest study of its kind. Researchers enrolled children who sought treatment at local clinics for moderate-to-severe diarrhoea and took stool samples to identify the microbe that was causing their illness.

Topping the list is rotavirus, which is spread by contact with stools. Vaccines against the well-known pathogen already exist, and today, the government of India, in partnership with Bharat Biotech, announced promising phase III trial results for a new vaccine.

Cryptosporidium, on the other hand, was a surprise to many researchers. The protozoan infects humans and animals, and can spread in contaminated water as well as from contact with human and farmyard faeces. “This had never been on the agenda before as a major pathogen in this clinical situation,” says George Griffin, an infectious-disease researcher at St George’s University of London, UK, and a member of the scientific advisory committee for the study. Although one drug is available to treat Cryptosporidium, more research is needed to understand the disease, says Griffin.