COVID-19 Scan for Sep 01, 2022

News brief

Study: Previous COVID-19 infection offers protection against BA.5

Infections with previous COVID-19 variants offer more protection against the Omicron BA.5 subvariant in vaccinated people compared with vaccinated people who had no previous  infections, according to a New England Journal of Medicine study yesterday.

The study was based on research conducted at the University of Lisbon in Portugal and is among the first studies to analyze protection against BA.5 among vaccinated and naturally infected people. The authors used the Portuguese national registry of COVID-19 cases to determine which variant likely caused infection based on date and variant predominance. Cases in patients age 12 and older were used.

The researchers found that while natural infections from 2020 and 2021 (when the wild-type strain and the Delta variant were predominant) offered some protection again BA.5, people infected with the BA.1 and BA.2 variants, at the beginning of 2022, who were also vaccinated had four times the protection as those who were only vaccinated.

"This study demonstrates, in the period of time analysed, that previous infection in vaccinated people (the so-called hybrid immunity) continues to confer for the variants that are known for their ability to evade the immune response, such as the subvariant currently dominant," said Valter Fonseca, MD, PhD, co-author of the study, in a press release from the Instituto de Medicina Molecular at the University of Lisbon.

The authors said their findings challenge the perception that protection afforded by previous BA.1 or BA.2 infection is very low.

"Our data indicate that this perception is probably a consequence of the larger pool of persons with BA.1 or BA.2 infection than with infection by other subvariants, and it is not supported by the data," they said.
Aug 31 N Engl J Med
Aug 31 University of Lisbon
press release


37% of a group of Maryland preschoolers with COVID-19 had no symptoms

An 8-month COVID-19 screening study of 175 Maryland households with at least one child aged 0 to 4 years finds that 37% of preschoolers had no symptoms, suggesting that screening only symptomatic children may not be enough to prevent outbreaks in this age-group.

A team led by Johns Hopkins University researchers analyzed weekly symptom questionnaires, self-collected nasal swabs, and sera from 690 participants in 175 Maryland households with one or more children younger than 5 years from Nov 24, 2020, to Oct 15, 2021. The study preceded the emergence of the more transmissible Omicron variant.

Of the 690 participants, 51.4% were female, 37.1% were aged 0 to 4 years, 14.5% were 5 to 17, 48.4% were 18 to 74, 87.4% were White, 6.2% were multiracial, 4.8% were Hispanic, 3.5% were Black, 2.2% were Asian, and 0.7% were of other races.

A total of 7.8% of all participants tested positive for COVID-19, including 22 of 256 children 0 to 4 years old (8.6%), 11 of 100 children aged 5 to 17 years (11.0%), and 21 of 334 adults (6.3%). Infection rates were 2.25 per 1,000 person-weeks among children younger than 5, 3.48 in the 5- to 17-year age-group, and 1.08 among adults.

Children were asymptomatic more often than adults (11 of 30 [36.7%] vs 3 of 21 [14.3%]), with preschoolers having no symptoms at the same rate as older children (7 of 19 [36.8%]). Symptom status didn't correlate with viral load or age, but the number of symptoms was associated with viral load in adults. The highest viral load was greater among participants infected with a Delta variant than among those infected with Alpha or non-variants of concern (VOCs).

Whole-household infection was rare. No fully vaccinated participants were infected with Alpha or non-VOCs, but six vaccinated and eight unvaccinated participants had Delta infections.

"Although the implications of these findings for household transmission remain to be evaluated, they suggest that SARS-CoV-2 infection may be underrecognized and that symptoms may not reflect infectiousness in young children," the researchers concluded.
Aug 31 JAMA Netw Open study

News Scan for Sep 01, 2022

News brief

Avails receives additional CARB-X funding for rapid susceptibility test

Diagnostics company Avails Medical announced today that it has received an additional $1.7 million in funding from CARB-X (the Combating Antibiotic-Resistant Bacteria Biopharmaceutical Accelerator) to continue developing a rapid electronic antibiotic susceptibility test (AST).

Company officials say the eAST system, which shortens the time to antibiotic susceptibility results from several days to an average of 5 hours, will enable healthcare providers to determine faster the best antibiotic treatment for patients with severe bloodstream infections. The system uses electronic biosensors that fit onto commercially available AST panels.

"Every hour counts for a patient with sepsis," Eszter Deak, PhD, director of scientific and medical affairs for Avails Medical, said in a company press release. "Avails' unique rapid eAST technology presents a meaningful opportunity to improve patient care by shortening the time to effective antibiotics at an affordable cost."

Avails, of Menlo Park, California, originally received $2.5 million in funding from CARB-X in February 2021.
Sep 1 Avails Medical press release


Online retailer a source of turtles in Salmonella outbreak, CDC says

In an update yesterday on a Salmonella Stanley outbreak tied to small turtles, the Centers for Disease Control and Prevention (CDC) said investigators have identified an online retailer as a source of the illnesses. Five patients reported buying turtles from before they got sick.

Also, officials reported 6 more infections and 3 more affected states, raising the outbreak total to 21 cases from 14 states. Eight people were hospitalized. The latest illness onset is Jul 15. Ages range from less than 1 year to 75 years, with a median of 14 years old.

The Florida Department of Health on Jul 20 collected samples from the facility, and whole-genome sequencing showed that the samples from the turtles are closely related to the strain from sick people. Sequencing bacteria from patients, turtles, and turtle environments didn't predict any resistance to antibiotics.

Small turtles have been linked to several Salmonella outbreaks in the past, and federal law bans their sale. However, they can sometimes be found online or at other outlets. The CDC has urged people in risk groups, such as those with underlying health conditions and families with young children, to avoid having turtles for pets.
Aug 31 CDC outbreak update

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