Fatal MERS case reported in Kuwait
Kuwaiti health officials have notified the World Health Organization (WHO) about a fatal MERS-CoV case, in a 78-year-old man from Kuwait City who owned camels and had frequent contact with them, according to a WHO statement today.
The man developed symptoms on Sep 8 and was hospitalized 5 days later. He died on Sep 19, and contact tracing among his household members and healthcare workers is under way, the WHO said. It added that the man had no known exposure to other MERS-CoV (Middle East respiratory syndrome coronavirus) cases or other risk factors in the 14 days before he got sick.
His infection is Kuwait's fourth MERS-CoV detection and its first since March 2014, according to a case list kept by FluTrackers, an infectious disease news message board.
Researchers pinpoint soft palate as key to flu virus evolution
The soft palate—the fleshy portion at the back of the roof of the mouth—appears to play a key role in influenza virus evolution, according to a ferret study by researchers with the National Institutes of Health (NIH) and the Massachusetts Institute of Technology (MIT).
The surprise findings were published as a letter today in Nature.
Previous research has shown that airborne transmissibility depends on whether a flu virus's hemagglutinin (HA) protein can bind to a certain type of receptor on human respiratory cells. Some viruses bind better to alpha 2-6 glycan receptors, which are found primarily in mammals (including people), while others are better adapted to alpha 2-3 glycan receptors, found primarily in birds.
To help determine genetic mutations that affect airborne transmission, the team took a 2009 H1N1 virus, which binds well to alpha 2-6 receptors, and made four mutations in its HA molecule to make it better suited to bind to alpha 2-3 receptors. They then introduced the virus into ferrets, which are typically studied to model human flu infections.
The next day, uninfected ferrets were placed in cages separated from infected ferrets by a perforated barrier. Nasal secretions were collected from the animals for 2 weeks. "To our surprise, the engineered flu virus was transmitted by the airborne route to uninfected ferrets just as well as the original non-mutated virus," said Kanta Subbarao, MD, of the NIH's National Institute of Allergy and Infectious Diseases, in an NIH press release.
Sequencing of the virus then determined that airborne transmission was associated with a single genetic change in the mutated virus's HA, and it appeared to have happened within 24 hours in the ferrets. Tissue samples from the animals' upper and lower respiratory tracts helped the investigators pinpoint the soft palate—which has surfaces facing both the mouth and nasopharyngeal region—as the key site for virus mutation.
"Historically, the soft palate has not been examined in animal models of influenza," said Subbarao.
The researchers are now trying to determine the exact role the soft palate plays in flu virus transmission, according to an MIT news release. They hypothesize that flu viruses with a superior ability to transmit through the air outcompete other viruses in the region.
Sep 22 Nature letter
Sep 22 NIH news release
Sep 22 MIT news release
Study shows poultry contact very common in Egyptian H5N1 cases
H5N1 avian flu cases during the peak months of November 2014 through April 2015 in Egypt were almost exclusively associated with poultry contact and were highly correlated to H5N1 poultry outbreaks, according to a study yesterday in Emerging Infectious Diseases.
Researchers from Egypt and the US Centers for Disease Control and Prevention analyzed data on 165 patients who were hospitalized for H5N1 during the 6-month study period, 51 of whom (31%) died. They compared their data with information from 342 Egyptian patients from Mar 20, 2006, through Apr 20, 2015, 299 of whom (87%) contracted H5N1 from November through April.
Of the 165 recent patients, 163 (99%) reported exposure to domestic poultry 1 to 2 weeks before symptom onset, with 35% recounting exposure to dead birds, 19% to sick birds, and 35% to healthy birds. About 58% of patients were involved in breeding, 24% in slaughtering, and 21% in preparing poultry. Seventy percent were exposed at home.
Only 1 patient among the 165 reported wearing personal protective equipment while handling poultry.
The investigators also reported six clusters of cases in the group comprising 12 patients.
They found the data between the earlier and more recent groups of patients to be similar. The percentage of cases that were part of a cluster was 7.3% in the more recent patients, compared with 6.8% in the earlier ones. The median percentage of monthly H5N1 detections among humans sampled was 5.4% in the recent cases, compared with 2.9% in the earlier cases, which was not a significant difference.
The researchers also noted that the number of human cases each month was highly correlated with the number of H5N1 poultry outbreaks each month as identified by agriculture officials.
The authors conclude, "Although the characteristics of case-patients during 2014-15 were similar to those of previous seasons and do not suggest increased efficiency of H5N1 transmission between humans, [the Ministry of Health] would be warranted in examining H5N1 virus circulating in Egypt for genomic markers of mammalian adaptation."
Sep 22 Emerg Infect Dis study
H5N1 strikes Nigeria, Vietnam as H5N2 hits South African ostriches again
Nigeria and Vietnam have confirmed multiple new H5N1 avian flu outbreaks, and South Africa has reported another H5N2 outbreak in ostriches, according to several reports posted by the World Organization for Animal Health (OIE) yesterday and today.
Reports of H5N1 outbreaks continue to mount in Nigeria, which has notified the OIE of 78 events this year after filing reports of 7 farm outbreaks yesterday and 1 today. Agriculture officials detailed 6 outbreaks yesterday and 1 today in Rivers district in the south, as well as an outbreak yesterday in Oyo district in the southwest. The event in Oyo began on Aug 17, while those in Rivers district began from Sep17 to Sep 19.
Together, 7,788 birds died of H5N1 among 27,932 chickens in the outbreaks, and the rest were destroyed to curb disease spread. The affected farms range in size from 1,209 to 13,203 susceptible poultry.
Sep 22 OIE report on Nigeria
Sep 23 OIE report on Nigeria
In Vietnam, H5N1 struck village flocks in Vinh Long province in the south and Ha Tinh in the northcentral part of the country, according to an OIE report yesterday.
The Vinh Long outbreak began Sep 6 and killed 940 birds, with the remaining 550 culled. The Han Tinh outbreak affected 200 poultry, killing 85. The surviving 915 birds were likewise euthanized.
Of 2,490 birds in both flocks, 1,140 birds were infected and 1,025 died, while 1,465 were destroyed. Response steps such as control of poultry movement and disinfection have been initiated, the report said.
Sep 22 OIE report on Vietnam
In South Africa two flocks comprising 1,472 ostriches on separate commercial farms were affected by low-pathogenic H5N2 avian flu in Western Cape province in the southwest, officials noted in an OIE report posted today.
One farm detected 303 cases among 494 birds, while the other had 40 cases in a flock of 978. No ostrich deaths were reported. Officials implemented screening and isolation steps but did not destroy any of the flocks. Since August 2014, South Africa has reported 29 outbreaks of H5N2 in ostriches.
Sep 23 OIE report on South Africa
Southern Hemisphere flu activity slows
Influenza in the Southern Hemisphere is showing signs of an end-of-season decline and is likely past its peak in Australia and New Zealand, the WHO said in an update.
Flu activity seems to be past its peak in Australia except in South Australia, where it continued to increase with influenza B strains dominating, followed by H3N2, an "A" strain. In New Zealand active flu might have peaked in mid-August. In that country, H3N2 and flu B have predominated throughout the season. Activity of influenza-like illness (ILI) was still above the seasonal threshold but below the alert level.
Flu activity remains low in temperate South America, but ILI activity sharply increased in Chile, along with increasing influenza detections. Influenza A is most common in that country.
African nations reported few flu virus detections, but influenza A appears to be dominant in East Africa and influenza B in South Africa.
Flu activity is low in tropical Asia and other Northern Hemisphere nations but picked up a bit in India, predominantly caused by 2009 H1N1.
Globally in recent weeks 74.5% of flu viruses have been A strains, while 25.5% are B strains. Of the influenza A viruses subtyped, 74.2% were H3N2 and 25.8% 2009 H1N1.
Sep 21 WHO update