Avian Flu Scan for Jul 26, 2016

News brief

Study shows wild birds not long-term reservoir for high-path H5 strains

The viruses causing outbreaks of highly pathogenic H5 avian flu that spread across North American poultry farms in late 2014 into the summer of 2015 did not persist in wild aquatic birds like ducks, suggesting they are not an ongoing source of highly pathogenic avian influenza (HPAI) viruses, according to a study yesterday in Proceedings of the National Academy of Sciences.

"The findings provide a scientific basis for the decision by officials to use culling and quarantines to stop the 2014-15 outbreak in domestic poultry," corresponding author Robert Webster, PhD, an emeritus member of the St. Jude Department of Infectious Diseases, said in a St. Jude news release. "Now, research is needed to identify the mechanism that has evolved in these wild birds to disrupt the perpetuation of highly pathogenic influenza."

St. Jude and other US researchers analyzed swabs from birds' throats and anal regions, as well as bird droppings from 22,892 wild ducks and other aquatic birds collected before, during, and after the 2014-15 HPAI outbreak, which has been linked to HPAI H5N8 from Asia. Samples were collected in the United States and Canada. The H5N8 virus reassorted in North American waterfowl and caused 248 avian flu outbreaks, the vast majority in the United States, and almost $5 billion in losses.

The waterfowl tested positive for H5 strains only during the outbreak—not before or after. In addition, a review of historical North American wild waterfowl samples turned up only low-pathogenic H5 viruses during the past 43 years.

The findings suggest that undiscovered mechanisms might restrict the emergence and perpetuation of HPAI in wild aquatic birds, the authors wrote.

They conclude, "Timely and efficient strategies used to successfully prevent and eradicate HPAIVs infecting poultry, without the use of vaccines, appear to complement natural biological mechanisms in disrupting the perpetuation and possible spread of HPAIVs by wild aquatic birds."
Jul 25 Proc Natl Acad Sci abstract
Jul 25 St. Jude press release


France reports new H5N1 avian flu outbreak in ducks

After reporting two outbreaks last week, French officials today confirmed a new highly pathogenic H5N1 avian flu outbreak in Dordogne department, according to a post from Avian Flu Diary, an infectious disease blog.

The affected flock comprises 24,000 ducks, according to a translated statement from France's agricultural ministry. The flock is only 400 meters from outdoor breeding chickens, officials reported yesterday.

Last week's outbreaks were in Dordogne and Aveyron departments. They ended 3 months with no known outbreaks. Since November 2015 the country has confirmed 80 outbreaks involving five new strains of European-origin avian flu, three of them highly pathogenic.
Jul 26 Avian Flu Diary post

News Scan for Jul 26, 2016

News brief

Flour recall expanded after 4 more E coli cases reported

General Mills expanded its recall of flour products yesterday after four more people in two states became sick with Escherichia coli infections.

To date, the Centers for Disease Control and Prevention (CDC) has reported that 46 people in 21 states have gotten sick with E coli strains in outbreak linked to General Mills products. The CDC also said one person developed hemolytic uremic syndrome, a type of kidney failure linked to E coli. The outbreak has resulted in 13 hospitalizations.

According to the CDC, infections have been reported from Dec 21, 2015, to Jun 25, with Minnesota reporting five cases, the most in any one state. General Mills said the illnesses occurred after people ate raw dough or batter, and the CDC warned consumers to not eat or bake with the recalled products.
Jul 25 General Mills
Jul 25 CDC


Candidate Ebola vaccine protects monkeys

A new study in the Journal of Infectious Diseases showed that FILORAB1, an inactivated rabies virus–based Ebola vaccine, was both safe and effective in rhesus and cynomolgus monkeys, and an updated vaccine that included glucopyranosyl lipid A as an immune-boosting adjuvant was 100% effective against lethal Ebola infection.

FILORAB1 was previously successful in preventing Ebola virus in mice, and the new data on monkeys is promising for potential human use.

"FILORAB1 builds on the excellent safety record of the current inactivated RABV vaccine approved for human use, which has been administered to tens of millions of people, including pregnant women and children, and addresses several shortcomings of the virally vectored EBOV vaccines currently in development by offering an improved safety profile, bivalency for a more common pathogen, and possibly improved stability for long-term storage," the authors wrote.

The Ebola outbreak that originated in West Africa in 2013 was the largest outbreak to date, with more than 28,000 cases. Ebola is very deadly, with a case-fatality rate of 53%. Since 2013, a number of Ebola vaccines have been in various stages of development.
Jul 24 J Infect Dis study


FDA updates safety warnings for fluoroquinolones

The Food and Drug Administration (FDA) has approved updated safety warnings for fluoroquinolone antibiotics.

The updated safety labels will now contain information about the risk of disabling and potentially permanent side effects associated with oral and injectable fluoroquinolones. Those side effects, which can occur in combinations hours to weeks after exposure to the antibiotics, involve tendons, joints, muscles, nerves, and the central nervous system.

In addition, the agency said that because of these side effects, the labels will say that fluoroquinolones should not be used to treat patients with acute bacterial sinusitis, acute exacerbation of chronic bronchitis, or uncomplicated urinary tract infections—unless patients with those conditions have no alternative treatment options. But fluoroquinolones are still considered a therapeutic option for more serious bacterial infections such as anthrax and plague.

The updated warning comes after an FDA safety review concluded that the risk of disabling and potentially permanent side effects associated with the antibiotics outweighed the benefits for patients with other treatment options. The agency had advised about those side effects in May but did not specify warning labels at that point.

The drugs receiving updated warnings include levofloxacin, ciprofloxacin, ciprofloxacin extended-release tablets, moxifloxacin, ofloxacin, and gemifloxacin.
Jun 24 FDA press release
May 12 CIDRAP News story on FDA safety warning


Nearly 60% of hospitalized patients given antibiotics for asthma

Findings from a large retrospective study indicate that a significant percentage of patients hospitalized for asthma are receiving inappropriate treatment with antibiotics.

In a research letter published yesterday in JAMA Internal Medicine, US researchers reported that, out of 51,951 patients hospitalized with asthma in 2013 and 2014, 58.2% were treated with antibiotics at some point during their stay, despite the lack of any indication for antibiotic therapy. Roughly 40% were prescribed antibiotics on their first day. The most commonly prescribed antibiotics were macrolides, quinolones, third-generation cephalosporins, and tetracyclines.

The authors said the high rate of antibiotic treatment could be attributed to the difficulty of differentiating between bacterial and non-bacterial infections and distinguishing asthma from chronic obstructive pulmonary disease. But they also suggested that "gaps in knowledge" about the benefits of antibiotic therapy for asthma may play a role. The authors noted that current guidelines recommend against using antibiotics for exacerbations of asthma unless there is a concurrent infection.

"These findings suggest a significant opportunity to improve patient safety, reduce the spread of resistance, and lower spending through greater adherence to guideline recommendations," the authors said in the letter.
Jul 25 JAMA Intern Med research letter

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