Flu Scan for Dec 12, 2014

News brief

US flu activity, H3N2 mismatch both increase

Though still below epidemic thresholds, US influenza activity has begun to pick up, and the vaccine mismatch with circulating H3N2 strains has reached two-thirds, the Centers for Disease Control and Prevention (CDC) said today in its weekly update.

In addition, two more children died from flu.

Of 16,093 specimens tested by US labs, 3,415 (21.2%) were positive for influenza for the week that ended Dec 6, up from 17.0% the week before. And 6.0% of all deaths were attributed to pneumonia and influenza, which is up from 5.4% the week and inching closer to the epidemic threshold of 6.6%.

Eight of the 10 US regions experienced elevated activity of influenza-like illness (ILI) in outpatients, the same as the previous week. The Midwest and South had the highest flu activity. The CDC's region that includes Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin reported 27.5% of samples positive for influenza, and the region that includes Arkansas, Louisiana, New Mexico, Oklahoma, and Texas reported 26.0%.

Puerto Rico and six mostly southern states reported high ILI activity, the same as the week before. More dramatically, 14 states reported widespread flu activity, up from 6 states.

Among the 3,415 influenza-positive specimens, 3,252 (95.2%) were influenza A and 163 (4.8%) were influenza B. Of the 1,261 "A" viruses that were subtyped, 1,254 (99.4%) were H3N2 and only 7 (0.6%) were 2009 H1N1.

A total of 133 of 197 H3N2 viruses tested, or 67.5%, did not match well with the H3N2 component in the vaccine. That is up from 58% the week before.

The CDC reported two new pediatric deaths from flu, both in the week that ended Nov 29. One was caused by H3N2 and the other by an influenza A virus that was not subtyped.
Dec 12 CDC FluView update
Dec 5 CIDRAP News story on strain mismatch and vaccine issues

Study: Unvaccinated kids have much higher flu risk than adults

Children who have not been vaccinated for influenza have much higher flu attack rates than unvaccinated adults, according to a study yesterday in BMC Infectious Diseases.

Researchers analyzed a systematic review of 34 randomized controlled trials. The trials evaluated a total of 94,821 participants during 47 flu seasons from 1970 to 2009.

Unvaccinated adults experienced a flu attack rate of 3.5%, while the attack rate in children was more than quadruple that, at 15.2%. Overall attack rates tended to be higher when flu was diagnosed with hemagglutination inhibition assay (HIA) either alone or in combination with polymerase chain reaction (PCR) than they were when diagnosed with PCR alone.

The influenza type B attack rate in unvaccinated children was more than nine times the adult rate (5.5% in children and 0.6% in adults). Influenza type A, however, caused more disease, with an attack rate of 12.3% in unvaccinated children and 2.3% in unvaccinated adults.

The study was funded by GlaxoSmithKline and included GSK researchers.
Dec 8 BMC Infect Dis study

Egypt reports 2 new H5N1 cases, 1 fatal

Egyptian officials have confirmed H5N1 avian flu in a 33-year-old woman and 16-month-old girl in Sohag governorate, with the former case proving fatal, Reuters reported today.

The woman died after being admitted to a hospital, Egypt's health ministry said, and the child has been hospitalized since Dec 7. The woman's death is the eighth H5N1-related fatality in the country this year. Reuters said the 2 infections bring the country's 2014 H5N1 case total to 16, but other media reports say 15.

Sohag governorate is in central Egypt along the Nile River.

Since 2003, the World Health Organization has confirmed 668 global cases in 16 countries as of Oct 2, including 393 deaths.
Dec 12 Reuters story

News Scan for Dec 12, 2014

News brief

CDC reports 28 more EV-D68 cases, 1 polio-like illness

After several weeks with no new reports of enterovirus D68 (EV-D68) respiratory infections, the Centers for Disease Control and Prevention (CDC) has reported 28 more illnesses, raising the national count since August to 1,149 cases in 48 states and Washington, DC. But an official said the agency is not aware of any new case clusters.

In addition, the agency has identified one more case of acute flaccid myelitis (AFM), a polio-like illness that involves unexplained limb weakness in children and seems related to EV-D68. The new AFM count is 94 cases in 33 states.

EV-D68, which was rare until recently, typically triggers cold-like symptoms but can cause a severe respiratory illness, almost exclusively in children, many of whom have asthma. The CDC says the pathogen has been the most common enterovirus identified in the United States this year.

Before yesterday's update, the CDC count of EV-D68 cases had remained at 1,121 in 47 states since Nov 20. The new update mentions 48 states but does not name the new state added to the list.

CDC spokeswoman Jeanette St. Pierre, when asked about the increase in cases, said today, "The number we are reporting includes cases confirmed by the CDC and the states. Sometimes there is lag time for the specimens reaching the CDC. We are not aware of a new cluster of cases."

Regarding the AFM cases, a CDC official said recently that close to half of the AFM patients had tested positive for EV-D68 in nasal or stool samples, suggesting a likely link between the two conditions. But the connection was not certain, because the virus had not been found in any cerebrospinal fluid samples, which would signal infection in the nervous system.

The CDC has said that 12 patients died after EV-D68 infections, but it has not reported any conclusions about the role of the virus in the deaths, saying that determination is up to the states. The number of such deaths listed by the CDC has not changed recently. In October, New Jersey officials said EV-D68 contributed to the death of a 4-year-old boy who died in his sleep.
CDC 2014 EV-D68 page
CDC Dec 12 update on AFM cases
Related Dec 2 CIDRAP News story
Related Nov 21 CIDRAP News item

NRC/IOM symposium will air gain-of-function research issues

The National Research Council (NRC) and Institute of Medicine (IOM) will hold a 2-day symposium next week to discuss issues related to "gain-of-function" (GOF) research on certain viruses, as part of an effort to develop a US policy on the controversial topic while funding is suspended.

The symposium will take place Dec 15 and 16 at the National Academy of Sciences Building in Washington, DC, and will be streamed over the Web.

In October the Obama administration announced it was suspending funding of GOF studies on influenza, MERS-CoV (Middle East respiratory syndrome coronavirus), and SARS (severe acute respiratory syndrome) coronavirus to allow time to assess risks and benefits and develop a federal policy.

The term GOF is generally used to refer to experiments that involve enhancing the pathogenicity, transmissibility, or host range of a pathogenic microbe, with the aim of better understanding disease pathways and developing vaccines and drugs. It emerged as a major issue in 2011 in connection with two studies that resulted in H5N1 avian flu viruses with increased transmissibility in ferrets.

The aim of the symposium, according to an NRC/IOM statement, is to "examine the underlying scientific and technical questions that are the source of current discussion and debate over GOF research involving pathogens with pandemic potential." It will look at potential risks and benefits of GOF research and whether other research methods might yield similar knowledge.

The conference is being organized by an ad hoc NRC/IOM committee chaired by IOM member Harvey V. Fineberg, MD, PhD. Among the many experts expected to participate is Yoshihiro Kawaoka, DVM, PhD, of the University of Wisconsin, author of one of the two H5N1 studies that put GOF research in the spotlight.

In related news, several of the leading voices in the GOF research debate aired their views this week in a question-and-answer article in Nature Reviews Microbiology. The authors are W. Paul Duprex, PhD, of the Boston University School of Medicine; Ron A. M. Fouchier, PhD, of Erasmus Medical Center in the Netherlands; Michael J. Imperiale, PhD, of the University of Michigan; Marc Lipsitch, PhD, of the Harvard School of Public Health, and David A. Relman, MD, of Stanford University.
Information on Dec 15-16 GOF symposium, with Webcast link
GOF symposium agenda
Oct 17 CIDRAP News item on GOF funding pause
Dec 8 Nat Rev Microbiol article