Flu Scan for Feb 26, 2015

News brief

WHO recommends 2 strain changes for next flu vaccine

The World Health Organization (WHO) today recommended changing two of the three strains in trivalent flu vaccines for use in the Northern Hemisphere's 2015-16 flu season.

First would be replacing the H3N2 in the current vaccine with the A/Switzerland-like virus, which showed up in small numbers after last season's recommendations were made but which has dominated in the United States this flu season. US health officials have said the mismatch between this year's vaccine and the circulating strain lowered efficacy, contributing to a more difficult flu season.

Second would be switching out the B/Massachusetts strain with B/Phuket, which, like the former, is from the Yamagata lineage. For quadrivalent vaccines that contain two influenza B strains, the WHO recommended adding B/Brisbane, which belongs to the Victoria lineage.

These new vaccine recommendations from the WHO for the Northern Hemisphere match the ones made last September for the Southern Hemisphere's upcoming flu season, which typically starts in May.

Because it takes several months to prepare vaccine viruses and grow them in eggs and cell culture, the WHO makes its recommendations several months in advance, based on its global analysis of circulating flu strain patterns and genetics. It will make its next recommendation for the Southern Hemisphere in September.
Feb 26 WHO strain selection report

China reports another H7N9 case, WHO weighs in on H7N9 patterns

Health officials in China's Zhejiang province yesterday reported an H7N9 avian influenza infection in a 49-year-old man from the city of Quzhou, according to a translation of an official report from there posted by FluTrackers, an infectious disease news message board. The man had been exposed to poultry and is hospitalized.

The World Health Organization (WHO) said today in its Northern Hemisphere flu strain selection report that China has reported 148 human H7N9 cases from Sep 24, 2014, through Feb 23, which is close to the 153 cases FluTrackers has registered during the same time period. FluTrackers bases its list on translations of municipal and provincial health department reports.

According to an H7N9 case list kept by FluTrackers, the new infection lifts the global total to 614. The World Health Organization (WHO) said in a flu overview today that it has received reports of 602 H7N9 infections, 227 of them fatal. Most were from China, but travel-linked cases have also been reported from Taiwan, Hong Kong, Malaysia, and Canada.

Compared with H7N9 activity in China last winter, cases in the third wave started gradually, increasing in November 2014 and again in January of this year but not as sharply as in January 2014.

The epidemiology of H7N9 illness in humans hasn't changed, with most infections occurring in people who had contact with poultry or poultry environments, the WHO said. It added that a few small human clusters have been detected, and though human-to-human spread can't be ruled out, transmission chains have been short, with no evidence of spread into the wider community.

The H7N9 virus does seem to pass more easily from birds to humans than the pattern seen with H5N1 avian influenza, according to the WHO.

The WHO said about 36% of H7N9 infections have been fatal, but it is not known how many asymptomatic or mild infections are occurring.
Feb 26 FluTrackers thread
FluTrackers H7N9 case list
Feb 26 WHO strain selection report
Feb 26 WHO influenza overview

News Scan for Feb 26, 2015

News brief

ACIP recommends meningitis B vaccine for high-risk groups

The US Advisory Committee on Immunization Practices (ACIP) today voted unanimously to recommend the use of meningococcal group B vaccines in high-risk groups, such as those with low immunity and college students threatened by outbreaks.

The recommendation comes in the wake of federal approval of two serogroup B vaccines in recent months—Wyeth's Trumenba last October and Novartis's Bexsero in January.

Before those approvals, the United States had no licensed vaccine for group B meningococcal disease, though there were vaccines for the A, C, Y, and W-135 serogroups. When small outbreaks struck two campuses in 2013, the Food and Drug Administration allowed importation of group B vaccines under special rules.

In noting the ACIP's action today, Novartis officials welcomed the ACIP action but said they hope the committee will make a broader recommendation at its next meeting.

"Today's high-risk recommendation does not cover the majority of adolescents and young adults in the US, who are at risk for contracting MenB," said Andrin Oswald, head of Novartis Vaccines, in an e-mailed statement.

"The MenB cases in recent weeks at Providence College, University of Oregon and Yale University all serve as a sobering reminder of the importance to act before additional individuals contract this potentially life-threatening disease," he added. "We hope that ACIP will soon include MenB vaccines in a broader recommendation to help ensure everyone in this age range is aware of and has access to the vaccine."

Novartis officials said many colleges require students to get the vaccine for meningitis A, C, W, and Y, but a group B vaccine is not yet required.

The ACIP's recommendations are normally approved by the Centers for Disease Control and Prevention.
Related Feb 25 CIDRAP News item
Related Jan 23 CIDRAP News item

Study notes high pneumonia burden in young children

Children younger than 5 years old account for 70% of pediatric pneumonia hospitalizations and viruses are far more often to blame for pneumonia in kids than are bacteria, according to a study today in the New England Journal of Medicine.

The study, by Centers for Disease Control and Prevention (CDC) researchers, looked at data from 2,358 kids who had radiographically confirmed pneumonia in children's hospitals in Memphis, Nashville, and Salt Lake City from January 2010 to June 2012.

Among 2,222 of those who had specimens available for both bacterial and viral testing, a pathogen was detected in 1,802 (81%). One or more viruses were detected in 1,472 (66%) of these children. Bacteria were detected in 175 (8%), and bacteria and viruses were present in 155 (7%).

The researchers estimated an annual pneumonia incidence of 15.7 per 10,000 children. If that number were projected to a US population of roughly 74 million kids, it would mean more than 116,000 children are hospitalized each year from pneumonia in the United States. The highest incidence was among children younger than 2 years old (62.2/10,000).

Respiratory syncytial virus (RSV), which was found in 28% of specimens, was the most common pathogen detected, followed by rhinovirus (27%) and human metapneumovirus (HMPV, 13%). RSV, adenovirus, and HMPV were more common in children younger than 5 compared with older children, while the reverse was true for Mycoplasma pneumoniae.

Coauthor Andrew Pavia, MD, chief of pediatric infectious diseases at the University of Utah School of Medicine, said in a university press release, "Our results are consistent with previous findings, and support continuing immunization efforts to maintain the reduction in bacterial pneumonia."

CDC Director Tom Frieden, MD, MPH, said in a CDC news release, "This ground-breaking study shows how badly we need faster, less-expensive diagnostic tests for doctors to accurately diagnose the cause of pneumonia so they can effectively treat it." He said that the annual hospital cost of pneumonia in US children is about $1 billion.
Feb 26 N Engl J Med abstract
Feb 25 University of Utah press release
Feb 25 CDC news release

FDA approves new antibiotic, Avycaz

Today the US Food and Drug Administration (FDA) approved Avycaz (ceftazidime-avibactam), a new antibiotic, to treat adults who have limited or no alternative treatment options. The specific conditions the drug is approved for are complicated intra-abdominal infections, in which the agent is used in combination with metronidazole, and complicated urinary tract infections, including pyelonephritis, a type of kidney infection.

Avycaz is a fixed-combination drug containing ceftazidime, a previously approved cephalosporin, and avibactam, a new beta-lactamase inhibitor, the FDA said in a press release.

"It is important that the use of Avycaz be reserved [for] situations when there are limited or no alternative antibacterial drugs for treating a patient's infection," said the FDA's Edward Cox, MD, MPH.

Avycaz is the fifth approved antibacterial designated as a Qualified Infectious Disease Product (QIDP), the agency said. A QIDP is given to antibiotics to treat serious infections, and the designation allowed Avycaz an expedited review process.
Feb 26 FDA press release