COVID-19 Scan for Jan 18, 2022

News brief

Study suggests 3 Pfizer vaccine doses may protect against Omicron

Today a study from Germany published in Science shows three doses of the Pfizer-BioNTech COVID-19 vaccine raised antibody levels against the highly transmissible Omicron (B.1.1.529) variant.

The study was based on sera from 51 participants, which was challenged with Wuhan, Beta, Delta, or Omicron pseudoviruses. The participants had received either two or three doses of the Pfizer vaccine. Though neutralizing antibodies are just one measure of vaccine effect and don't demonstrate effectiveness per se, the authors say they can be strongly predictive of the degree of immune protection against symptomatic SARS-CoV-2 infection.

Twenty-one days after the primary two-dose series, sera samples had a significant reduction in neutralizing activity against Omicron; after two doses, geometric mean neutralization titers (GMT) against Omicron pseudovirus were 22.8-fold lower than the Wuhan reference pseudovirus, and 20 out of 32 immune sera displayed no detectable neutralizing activity against Omicron.

But within 4 weeks of a third dose, Omicron-neutralizing titers had increased 23-fold compared with two doses.

"Our data show that a third BNT162b2 [Pfizer] dose effectively neutralizes Omicron at a similar order of magnitude as was observed after two doses of BNT162b2 against wild-type SARS-CoV-2," the authors concluded.
Jan 18 Science


Fewer racial minorities given monoclonal antibodies to treat COVID-19

Analysis of data from 41 healthcare systems participating in the US National Patient-Centered Clinical Research Network shows that monoclonal antibodies (mAbs) were administered to Black, Asian, Hispanic, and other minority-race COVID-19 outpatients at lower rates than their White peers.

Led by Centers for Disease Control and Prevention (CDC) researchers, the study found smaller racial differences in the use of the antiviral remdesivir and the corticosteroid dexamethasone in hospitalized COVID-19 patients. The data, collected from March 2020 to August 2021, was published late last week in Morbidity and Mortality Weekly Report (MMWR).

Among the 805,276 COVID-19 patients who received mAbs, their use was infrequent, with average monthly use of 4% or less for all racial groups. Hispanic patients were given mAbs 58% less often than other patients, and Black and Asian patients and those of other races were given the antibodies 22%, 48%, and 47% less often, respectively, than their White counterparts from November 2020 to August 2021.

Of the 120,204 inpatients who received remdesivir and dexamethasone, Hispanic patients were given dexamethasone 6% less often than others, and Black patients received remdesivir 9% more often than White patients.

"This could indicate racial and ethnic differences in clinical indications for medication use (e.g., age distribution and prevalence of comorbidities) or could be reflective of varying prescribing practices, protocols, and drug access by institutions that serve populations of different racial and ethnic distributions," the researchers said.

Reducing racial inequities in access to COVID-19 therapies requires patient and clinician awareness of the problem and potential solutions; resources; and action by government, private entities, and community- and faith-based organizations, the researchers said.

"Bringing health care to populations facing barriers in access to mAb via a mobile infusion unit or via telehealth providers has been shown to increase mAb use, decrease severe outcomes, and reduce costs," they wrote. "Efforts to reduce racial and ethnic disparities with equitable outpatient COVID-19 treatment access, practices, and supportive systems are urgently needed."

The authors emphasized that while mAbs, remdesivir, and dexamethasone can reduce COVID-19–related illness and death and relieve the hospital burdens, vaccines and other preventive measures remain the best defenses against infection.
Jan 14 MMWR study

News Scan for Jan 18, 2022

News brief

US detects H5N1 avian flu in wild duck as Europe, Africa note more H5N1

The US Department of Agriculture (USDA) on Jan 14 announced that highly pathogenic H5N1 avian influenza was detected in a wild wigeon in South Carolina, marking the first time the Eurasian strain of the virus has been detected in the United States since 2016.

The finding follows the recent detection of high-path H5N1 in wild birds and poultry in Canada's Newfoundland and Labrador region.

The bird was harvested by a hunter in Colleton County, located in the state's Lowcountry region on its southern coast, according to a statement from the USDA's Animal and Plant Health Inspection Service (APHIS). It was tested as part of ongoing active surveillance. According to a notification from the World Organisation for Animal Health (OIE), the sample was collected on Dec 30.
Jan 14 APHIS statement
Jan 14 OIE report

In other avian flu developments, Croatia and Spain recently reported new H5N1 events in poultry, according to OIE reports. Croatia's outbreak began on Jan 10 at a backyard facility in Osijek-Baranja County that houses layers, ducks, and ornamental pigeons. The virus killed 13 of 52 susceptible birds, and the rest were culled to curb the spread of the virus.

Spain reported an H5N1 outbreak at a turkey farm in Castile and Leon region, which started on Jan 13 and killed 966 of 18,900 susceptible poultry.

In Africa, Togo reported an H5N1 outbreak at layer farm in Maritime region that began on Jan 1, killing 1,801 of 11,450 birds.
Jan 14 OIE report on H5N1 in Croatia
Jan 18 OIE report on H5N1 in Spain
Jan 15 OIE report on H5N1 in Togo


H9N2 avian flu infects 4 more in China

China recently reported four more human H9N2 avian flu infections, all involving children and all with November and December illness onsets, Hong Kong's Centre for Health Protection (CHP) said in its regular avian influenza update.

Two of the patients, a 3-year-old boy and a 3-year-old girl, are from Hubei province. The others include a 7-year-old girl from Jiangsu province and a 14-year-old girl from Guangxi province. The report didn't include any details about their exposure to the virus.

H9N2 is common in Asian poultry, and sporadic infections are known to occur in people who have contacts with poultry and poultry environments. Infections are mild and are typically reported in children. In November, however, China reported a fatal case in an adult—a 39-year-old man from Guizhou province.
Jan 18 CHP avian flu report


FDA details contamination clues in probe of hydroponic greens Salmonella

Marking the first investigation into an outbreak tied to a domestic hydroponic growing operation, the US Food and Drug Administration (FDA) late last week issued the findings related to a Salmonella Typhimurium event linked to prepackaged salad greens that sickened 31 people from four states last summer.

In earlier outbreak announcements, federal officials had identified the grower as Bright Farms, based in Rochelle, Illinois.

The FDA said though the root cause of the contamination was not identified. But it added that FDA and partner investigators identified several potentially contributing factors, including a different Salmonella serotype in pond water used to grow the leafy greens, as well as growth media storage practices, water management practices, and sanitation issues at the facility that weren't enough to prevent contamination.

Officials isolated the outbreak strain in a storm water basin next to the farm, but it wasn't clear if it was the source of the greens contamination. The FDA made several recommendations for the company and other similar growers, including ensuring that growing pond water is safe for its intended use.
Jan 14 FDA statement

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