Flu Scan for Nov 04, 2014

News brief

Study finds probable H5N8 transmission between wild and domestic ducks

Strains of the H5N8 avian influenza virus may be easily transmitted by wild mallards and cause severe illness in domestic ducks, according to a study published yesterday in Emerging Infectious Diseases.

Researchers at South Korea's Animal and Plant Quarantine Agency evaluated the pathogenicity of the Gochang1, Buan2, and Donglim3 strains of H5N8 in wild mallards, wild Baikal teals, and domestic Pekin ducks. Pathogenicity of the H5N8 strains was also compared with H5N1 avian flu strains.

Pathogenicity tests involved H5 hemagglutination-inhibition (HI) assays, oropharyngeal and cloacal swabs, and tissue sampling from dead birds. Neither the H5N8 nor the H5N1 strains caused severe illness or death in wild mallards.

Moderate pathogenicity was reported in domestic ducks exposed to the H5N8 strain, causing a 0 to 20% mortality rate, the study reported. All uninoculated domestic ducks (the "contact" ducks) also tested positive for H5N8 viral titers, suggesting that transmission of H5N8 from wild to domestic breeds occurred during the study.

The study also found that H5N8 viral shedding and replication lasted significantly longer in mallards than in domestic ducks, and that mallards shed more virus when infected with H5N8 compared with H5N1. These findings suggest that wild ducks may be long-distance vectors for H5N8 strains, the authors wrote.

Given the implications for transmission from wild birds, the researchers recommended increased surveillance of H5N8 in domestic ducks.
Nov 3 Emerg Infect Dis study

WHO: Global flu activity low except on some Pacific islands

Global influenza activity is generally low, with the exception of increased influenza-like illness (ILI) reported on several Pacific islands, the World Health Organization (WHO) said in its weekly update yesterday.

Flu activity remained low in North America, Africa, and Asia and at inter-seasonal levels in Europe, the agency said. In tropical countries of the Americas, flu detections decreased, with respiratory syncytial virus (RSV) causing most cases of ILI.

In the Southern Hemisphere, flu activity has reached inter-seasonal levels except on the Pacific islands of Micronesia, Fiji, French Polynesia, Kiribati, Samoa, Vanuatu, and Wallis & Futuna.

In its weekly flu virology report, the WHO said that 59% of 1,318 influenza specimens were positive for influenza A, and 41% were positive for influenza B. Of the 420 "A" strains subtyped, 374 (89%) were H3N2 and 46 (11%) were 2009 H1N1.
Nov 3 WHO global flu update
Nov 3 WHO influenza virology report

News Scan for Nov 04, 2014

News brief

Citing good trial results, Sanofi to seek approval for dengue vaccine

Sanofi Pasteur announced yesterday it will seek approval of its dengue virus vaccine in a number of dengue-plagued countries, following completion of a large phase 3 trial that showed overall vaccine efficacy of about 61%.

The results of the trial, involving close to 21,000 children in Brazil, Colombia, Mexico, Honduras, and Puerto Rico, were published yesterday by the New England Journal of Medicine. It was the second and larger of two phase 3 trials the company has conducted. Sanofi's vaccine is the furthest developed of several experimental dengue vaccines.

In the blinded trial, children between ages 9 and 16 were assigned in a 2-to-1 ratio to receive three doses of Sanofi's tetravalent (four-strain) dengue vaccine or a placebo at 0, 6, and 12 months. The vaccine is a recombinant, live attenuated formulation. The children were followed for 25 months.

The trial included 20,869 children. The investigators confirmed 176 dengue infections in the vaccine group and 221 cases in the control group, for an overall efficacy of 60.8% (95% confidence interval [CI], 52.0% to 68.0%).

There were 12 severe dengue cases, of which 1 was in the vaccine group. That signaled a vaccine efficacy of 95.5% (95% CI, 68.8%-99.9%) against severe disease in those who received at least one dose, according to the report. Vaccine efficacy against hospitalization for dengue was calculated at 80.3% (95% CI, 64.7% to 89.5%).

Vaccine efficacy against the four dengue virus serotypes ranged from 42.3% (type 2) to 77.7% (type 4), the report says.

Oliver Charmeil, Sanofi Pasteur's CEO and president, said in a press release, "We plan to submit the vaccine for licensure in 2015 in endemic countries where dengue is a public health priority. We are committed to supporting countries' ambitions to significantly impact the human and economic burden of dengue through comprehensive vaccination programs."

The results of Sanofi's other phase 3 trial were reported in July. In that study, involving 10,275 children in Southeast Asia, the vaccine was found to have an overall efficacy of 56.5%.
Nov 3 N Engl J Med abstract
Related Sep 3 CIDRAP News item
Jul 11 CIDRAP News item about Asian trial

Saudi Arabia reports 2 new MERS cases and 3 recoveries

Saudi Arabia's Ministry of Health (MOH) confirmed two new MERS-CoV cases today in Riyadh, as well as three recoveries in previously reported case-patients.

The new cases occurred in a 31-year-old woman and 33-year-old man. The MOH reports that both patients are hospitalized in a general ward.

Neither patient is a healthcare worker (HCW), had preexisting disease, or had contact with animals. The MOH is investigating whether they had contact with suspected or confirmed MERS-CoV (Middle East syndrome coronavirus) cases in clinical or community settings.

The MOH also reported recoveries in three previously reported MERS-CoV case-patients: a 38-year-old male HCW from Taif, a 42-year-old female HCW from Riyadh, and a 17-year-old boy from Riyadh. All had preexisting disease.

The new MOH report pushes the Saudi MERS-CoV case count to 793 total cases (15 active) and 440 recoveries. Of the 793 cases, 338 have proved fatal.
Nov 4 Saudi MOH update
Nov 3 CIDRAP News story on recent WHO confirmations in Saudi Arabia and Qatar

In related news, the Saudi MOH today updated its MERS infection-control procedures.

"It is critical that all healthcare workers and facilities, public and private, follow these updated protocols," said Dr. Anees Sindi, deputy commander of the MOH's Command & Control Center, in an MOH press release. "With more than 70 percent of recent MERS-CoV cases resulting from secondary infections, mainly acquired in the hospital, we have recognized the need to implement stricter infection-control measures across the health system.

"Sporadic cases of the disease, which are thought to be caused by unprotected contact with camels, are likely to happen," Sindi added. "Secondary infections, however, should be preventable."

The protocols include ensuring hospital workers are familiar with the latest MERS-CoV case definition, using appropriate protective equipment, and calling a hotline to report cases and receive guidance. The MOH also noted that it has created 17 regional MERS specialist hospitals across the country to combat the outbreak.
Nov 4 MOH press release