News Scan for Mar 15, 2021

News brief

Small Saudi study finds 12% in ICU had both MERS and COVID-19

Out of 67 intensive care unit (ICU) patients who underwent simultaneous SARS-CoV-2 and Middle East respiratory syndrome coronavirus (MERS-CoV) testing in Saudi Arabia, 8 (11.9%) had coinfections, according to a new Travel Medicine and Infectious Disease study.

The study didn't find any anomalous symptoms or mortality rates, although the researchers say more data are needed around mortality.

The study ran from Mar 14 to Oct 19, 2020, and found that most coinfected patients were male (75.0%) and obese (87.5%). Average patient age was 44. The most common symptoms were cough (87.5%), history of fever (87.5%), and abdominal pain (75.0%), and the average hospital and ICU stay was 21.1 and 10.9 days, respectively. All eight were treated with supportive therapy and corticosteroids, and seven had to receive mechanical ventilation for an average of 6.7 days.

Final outcomes were 4 discharges (50.0%), 3 deaths (37.5%), and 1 unknown, as the patient was transferred and lost to follow-up.

"In this small case-series the combined infection was not associated with increased risk of death in comparison with mono-infection with MERS-CoV," the researchers write, noting that the estimated case mortality for MERS-CoV is also 37.5%. They added, however, that if the patient lost to follow-up died, then mortality would rise to 50%.

The researchers note that a previous Journal of Epidemiology and Global Health study on SARS-CoV-2 and MERS-CoV coinfections didn't find any instances in 99 hospitalized COVID patients from Mar 22 to May 31, 2020.
Mar 13 Travel Med Infect Dis study

 

Study: SARS-CoV-2 was evolutionarily poised to jump from bats to humans

SARS-CoV-2 has undergone few adaptations since it jumped from bats to humans, sparking the COVID-19 pandemic, a study published late last week in PLOS Biology shows.

UK, US, and Belgian researchers sequenced 133,741 human SARS-CoV-2 genomes from December 2019 to October 2020 and 69 coronavirus genomes from horseshoe bats to identify novel adaptations to the human host.

Lead author Oscar MacLean, PhD, of the University of Glasgow, said in a PLOS news release that the findings don't mean that there have been no changes, only that they have not been evolutionarily significant.

"This stasis can be attributed to the highly susceptible nature of the human population to this new pathogen, with limited pressure from population immunity, and lack of containment, leading to exponential growth making almost every virus a winner," MacLean said.

Coauthor Sergei Pond, PhD, of Temple University, said in the release that the speed of viral spread right from the beginning has been surprising. "Usually viruses that jump to a new host species take some time to acquire adaptations to be as capable as SARS-CoV-2 at spreading, and most never make it past that stage, resulting in dead-end spillovers or localised outbreaks," he said.

The researchers said that SARS-CoV-2 and related viruses did change significantly before the leap from bats to humans, meaning that their ease in jumping between host types had already evolved by then, likely without the need for an intermediary host like a pangolin.

"While an undiscovered 'facilitating' intermediate species cannot be discounted, collectively, our results support the progenitor of SARS-CoV-2 being capable of efficient human–human transmission as a consequence of its adaptive evolutionary history in bats, not humans, which created a relatively generalist virus," the authors said in the study.

SARS-CoV-2 variants such as B117 began surfacing toward the end of 2020 because more people had already been infected, said coauthor David Robertson, PhD, of the University of Glasgow, in the release. "This will select for variants that can dodge some of the host response," he said. "Coupled with the evasion of immunity in longer-term infections in chronic cases (e.g., in immunocompromised patients), these new selective pressures are increasing the number of important virus mutants."
Mar 12 PLOS Biology study
Mar 12 PLOS news release

 

H5N8 avian flu strikes poultry farm in Kuwait

Animal health officials in Kuwait reported a highly pathogenic H5N8 avian flu outbreak in poultry, marking another recent appearance of the virus in the Middle East.

The outbreak began on Mar 7 at a commercial poultry farm in Al Jahrah governorate in the east central part of the country, killing 1,900 of 7,000 susceptible birds. The surviving ones were culled.

Kuwait's reported its last H5N8 outbreak in November 2020.
Mar 12 OIE report on H5N8 in Kuwait

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