Flu Scan for Apr 03, 2015

News brief

Declining US flu season still having substantial impact

Although influenza in the United States continues to decline, it has now been elevated for 19 consecutive weeks, has caused seven more pediatric deaths, and continues to create record levels of hospitalization in the elderly, the Centers for Disease Control and Prevention (CDC) reported today in its weekly update.

The proportion of people seeing a healthcare provider for influenza-like illness (ILI) dropped from 2.2% to 2.0% last week, which is the national baseline. In the past 13 flu seasons ILI has remained at or above baseline levels for 1 to 19 weeks, with an average of 13 weeks.

Five of 10 US regions reported ILI activity at or above region-specific baselines, compared with 6 in the previous week, the CDC reported. However, Puerto Rico, Minnesota, and Oklahoma reported high ILI activity last week, compared with just Puerto Rico and Oklahoma the week before. Widespread flu was reported in four northeastern states, down from seven states across the country in the previous week.

The percent of specimens that tested positive for influenza was 10.8%, which was up from 10.6% the week before. About 80% of viruses subtyped were influenza B, up from 75% the week before and representing a typical late-season surge. Almost all the influenza A viruses subtyped were the H3N2 strain.

Of all deaths reported through the CDC's monitoring system last week, 6.9% were attributed to pneumonia and flu, which was below the epidemic threshold of 7.1%.

Of the 7 new pediatric deaths, 4 were attributed to H3N2, 2 to influenza B, and 1 to an unspecified influenza A subtype. They bring the season's total to 123. The previous week saw 9 flu-related pediatric deaths.

The rate of flu-related hospitalizations again climbed, from 58.4 to 59.9 per 100,000 population. And the rate of hospitalization in those 65 and over again hit a record high since the CDC began tracking that figure in 2005, rising from 289.7 to 296.2 per 100,000.
Apr 3 CDC weekly FluView report
Apr 3 CDC flu situation update

China reports 3rd recent H5N1 case in Yunnan province

Chinese health officials today confirmed a case of H5N1 avian flu in Yunnan province, the third case in that province in 11 days, Hong Kong's Centre for Health Protection (CHP) reported in a news release.

The case involved a 6-year-old boy in Chuxiong city. He developed a fever on Mar 23 and was hospitalized on Mar 25. He has since recovered after treatment, the CHP said, but it did not say whether he had recent contact with poultry, a known risk factor.

Provincial authorities on Mar 23 and Mar 25 reported cases in a 34-year-old man and a 17-year-old boy, respectively, both from Kunming, about 100 miles east of Chuxiong. The man had recent poultry exposure.

China has now confirmed five H5N1 cases in 2015. Egypt, in contrast, has had at least 128 cases this year.
Apr 3 CHP news release
Related Mar 25 CIDRAP News scan

News Scan for Apr 03, 2015

News brief

Glanders detected in donkey near Texas-Mexico border

A stray donkey that crossed from Mexico into Texas has tested positive for glanders, a highly contagious disease that primarily affects equines, the Southwest Farm Press reported this week.

The bacterium that causes glanders, Burkholderia mallei, has been classified by the US government as a category B bioterror agent, meaning it can be transmitted fairly easily but has a lower mortality rate than a category A agent.

The Texas Animal Health Commission (TAHC) reported that a mounted US Department of Agriculture (USDA) inspector corralled five Mexican donkeys just north of Presidio, Tex., near the Rio Grande, according to the story. The animals were isolated in USDA holding pens in Presidio, and one of them later tested positive for glanders.

"It is imperative that we remain vigilant in protecting our borders from disease intrusions such as Glanders," said Dee Ellis, DVM, state veterinarian and TAHC director, told the newspaper. "Early detection of Glanders and the immediate quarantine of these donkeys was critical in preventing and protecting against the spread of this foreign disease."

The TAHC is working closely with the USDA to monitor the situation along the border, the story said. Equine glanders was eliminated from the United States in 1942, and the last human case in the country was in 1934.
Apr 1 Southwest Farm Press story
CIDRAP-authored glanders overview

Experts weigh research challenges in Ebola countries

Two groups of infectious disease experts today addressed the challenges researchers face in doing efficacy trials in the face of waning Ebola levels in the outbreak countries, the options for addressing the problems, and the benefits of working out the study design issues now and for future outbreaks. The opinion pieces appeared in The Lancet and Science.

In the Lancet article, David Heymann, MD, a global health and infectious disease expert with the London School of Hygiene and Tropical Medicine, and two other colleagues from Europe discussed options for moving the Ebola vaccine forward if phase 3 studies stall, due to dropping disease levels.

They suggested that the study plans can be put on hold until an outbreak situation emerges. In the meantime, they wrote, authorities can work on a regulatory pathway that could consider accelerated approval based for the time being on safety and immunogenicity rather than on efficacy. The process could also include conducting studies on toxicology, defining the functional relationship between immune responses in people and in nonhuman primates, and reaching an agreement to pin down efficacy later.

The experts contended that the steps would encourages groups to stockpile the vaccine and manufacturers to produce it, which would help ensure that a vaccine supply would be available for quick deployment to outbreak hot spots to complete efficacy trials.
Apr 3 Lancet commentary

In the Science editorial, Marc Lipsitch, PhD, director of the Center for Communicable Disease Dynamics at the Harvard School of Public Health, and colleagues wrote that the challenges researchers are facing in doing efficacy studies in the outbreak region would probably be faced when developing vaccines for other emerging infectious diseases. They suggested three principles that are used to some degree in current Ebola vaccine trial designs that could be used to guide vaccine planning in other health emergencies.

Principles include block randomization within small centers, with analysis matched by center, stepped rollout, and adaptive design.

The authors observed that researchers are faced with balancing the epidemiology of the disease with the characteristics of the vaccines. They said that the ethics of speeding a vaccine to many people should be weighed with the need to evaluate efficacy.

Discussions take time against the backdrop of the need for expediency, they wrote. "The more such discussions can take place outside emergencies and establish general principles to inform vaccine trial designs in future outbreaks, the more effective the responses to such outbreaks will be."
Apr 3 Science commentary