News Scan for Jun 16, 2022

News brief

Africa sees significant jump in COVID-19 vaccination

Levels of COVID-19 vaccination in 31 African countries in the first 5 months of 2022 show a significant rise in COVID-19 immunization among high-risk groups, officials from the World Health Organization (WHO) African regional office said today at a briefing.

Nearly 50% of healthcare workers and people over age 60 have been fully vaccinated, up from 33% of health workers and 10% of people over 60 vaccinated by the end of 2021.

So far, two African countries—Mauritius and Seychelles—have met the 70% global target for overall population coverage, and Rwanda is expected to meet the target by the end of June. Nine countries have fully vaccinated 70% of the adult population, which is an emphasis in Africa, given that 45% of the population is in the lower-risk under-18 age-group.

Officials said 31 countries have mass vaccination campaigns scheduled for this year, and the WHO and its partners are focusing extra support for 14 countries that haven't yet vaccinated 10% of their populations.

Officials said Africa's COVID-19 cases were up slightly last week after a 3-week decline, mainly due to rises in East and North Africa.

Also, the WHO today welcomed a new licensing agreement between the Medicines Patent Pool and South Africa–based Biotech Africa to boost the supply and sale of COVID-19 serologic tests. WHO Director-General Tedros Adhanom Ghebreyesus, PhD, said in a statement that testing is the most effective way to get and keep ahead of the pandemic, adding that the agreement will leverage untapped manufacturing capacity to ensure easier access to affordable tests.
Jun 16 WHO African regional office press release
Jun 16 WHO statement


Boosters plus previous infection shown most protective against Omicron

According to a study yesterday based on COVID-19 cases in Qatar, protection afforded by natural immunity from prior infections was longer-lasting than from a primary mRNA vaccine series, but booster vaccine doses combined with prior infection provided the most protection against infections during the Omicron surge.

The study was published in the New England Journal of Medicine.

To conduct the study, researchers performed a national test-negative, case-control study in Qatar from Dec 23, 2021, through Feb 21, 2022, during the Omicron surge. They compared two doses of mRNA vaccines, three doses, natural immunity, and mixed immunity (from vaccines and natural infections).

Previous infection alone was 46.1% effective (95% confidence interval [CI], 39.5% to 51.9%) in protecting against infection with BA.2, an Omicron subvariant that surpassed the original (BA.1) Omicron strain in late March. Two doses of the Pfizer vaccine administered more than 6 months before the surge offered no protection (−1.1%; 95% CI, −7.1% to 4.6%), compared with three doses of Pfizer and no prior infection, which was 55.1% protective (95% CI, 50.9% to 58.9%).

The highest level of protection against BA.2 infection was in people who had a previous infection plus three doses of the Pfizer vaccine, which was 77.3% (95% CI, 72.4% to 81.4%).

Prior infections offered protection for up to 1 year, while a two-dose vaccine regimen offered little protection 6 months after the vaccine series was complete.

In addition, "previous infection alone, BNT162b2 [Pfizer] vaccination alone, and hybrid immunity all showed strong effectiveness (>70%) against severe, critical, or fatal Covid-19 due to BA.2 infection, " the authors wrote.

The authors concluded by saying the study shows the importance of vaccinating those with prior COVID-19 infections.

"Recent booster vaccination had moderate effectiveness, whereas hybrid immunity from previous infection and recent booster vaccination conferred the strongest protection against infection, at approximately 80%. All five forms of immunity were associated with strong and durable protection against Covid-19–related hospitalization and death," the concluded.
Jun 15 N Engl J Med


Study finds low 2-dose vaccine protection against Omicron in teens

A study today in Pediatrics of Pfizer-BioNTech COVID vaccine efficacy (VE) in teens finds that VE was lower against symptomatic Omicron infection than against Delta and decreased faster, from 51% initially to 29% after 180 days, compared with 97% and 90% for the same intervals against symptomatic Delta infection.

Researchers in Toronto conducted a test-negative study among children aged 12 to 17 years who were tested for SARS-CoV-2 by polymerase chain reaction (PCR) from Nov 22, 2021 (when Omicron was first detected) to Mar 6, 2022. They restricted their Delta analysis to before Jan 3, 2022, because of the drop-off in Delta cases as Omicron surged.

The investigators compared 9,902 Omicron cases with 19,953 test-negative controls and 502 Delta cases with 17,930 controls. In their Omicron analyses, 91% of tested teens had received two doses and 1.3% had received three doses, with 84.5% having an interval between the first two doses of less than 8 weeks.

They estimated VE against symptomatic Omicron infection of 51% (95% confidence interval [CI], 38% to 61%) for 7 to 59 days after a second dose, but it dropped to 29% (95% CI, 17% to 38%) after 180 days, compared with 97% (95% CI, 94% to 99%) and 90% (95% CI, 79% to 95%) for Delta.

Overall, two-dose VE against severe Omicron outcomes was 85% (95% CI, 74% to 91%) 7 days or more after a second dose and held steady over time. (Numbers were too small for a similar Delta analysis.) Three-dose VE against symptomatic Omicron infection was 62% (95% CI, 49% to 72%).

The authors conclude, "These results can inform third dose recommendations in adolescents, as 2-dose protection against symptomatic Omicron infection is relatively low and wanes over time, whereas protection of a second dose against severe outcomes is higher."
Jun 16 Pediatrics abstract


CDC reports 16 more kids' unexplained hepatitis cases, 290 total

In a weekly update, the US Centers for Disease Control and Prevention (CDC) yesterday reported 16 more unexplained hepatitis cases in kids, raising the national total to 290 cases under investigation. So far, 41 states or jurisdictions have reported cases, up from 39 the previous week.

The CDC has said case increases don't necessarily signal a spike in new cases, given that investigations stretch back to October 2021.

Earlier this week the CDC said a study of background levels of unexplained hepatitis didn't show a spike over the COVID-19 pandemic months. Writing in Morbidity and Mortality Weekly Report (MMWR), the authors said their findings are based on limited data and come with a lot of caveats.

They also didn't see a change in adenovirus type 40/41 activity during the pandemic months. They said the findings can't confirm or rule out a link between hepatitis and adenovirus, but it said the analysis provides useful context for ongoing investigations.

Though a definitive cause hasn't been identified, experts have said adenovirus involvement is a strong lead, but they are also looking at other exposure, including SARS-CoV-2 and toxins.

As investigations continue, Israeli researchers recently published a case series detailing five children who recovered from COVID-19 and later experienced liver injury. Two were previously healthy young infants who needed liver transplants. Three were kids ages 8 to 13 with hepatitis who recovered after treatment with steroids. None had other infectious or metabolic causes.
Jun 15 CDC unexplained hepatitis update
Jun 14 CDC MMWR report
Jun 10 J Pediatr Gastroenterol Nutr study

Stewardship / Resistance Scan for Jun 16, 2022

News brief

Urgent care stewardship linked to fewer inappropriate antibiotics

Pediatric urgent care (UC) centers involved in a multisite quality improvement (QI) study saw significant reductions in inappropriate antibiotics for three target diagnoses, a team of US researchers reported yesterday in Pediatrics.

The study involved 157 participants from 20 pediatric urgent care centers who responded to an invitation from the Society of Pediatric Urgent Care Centers to participate in a QI collaborative aimed at improving antibiotic prescribing for acute otitis media (AOM, or ear infection), otitis media with effusion (OME), and pharyngitis.

From June 2019 to December 2019, participating sites completed multiple intervention cycles from a menu of publicly available antibiotic stewardship intervention tools, including provider and patient education, provider communication training, delayed prescribing, and social media. The primary outcome was the rate of inappropriate antibiotic prescriptions for all target diagnoses.

Data from 3,833 patient encounters showed that the rate of inappropriate prescribing for all encounters fell from 60.3% at the beginning of the intervention to 27.8% at the end, for a relative reduction of 53.9%. The biggest reductions in inappropriate prescription rates were observed for AOM (57% to 36.6%) and pharyngitis (66.9% to 11.7%), which were the two most common encounters, accounting for 52% and 40.9% of all diagnoses, respectively. Inappropriate prescribing for OME, which accounted for only 7.1% of patient encounters, fell from 54.6% to 48.4%.

The study authors say that while the interventions are affordable, accessible, and easy to implement, they also have low reliability, and the changes can be difficult to maintain "because new people enter the system, and humans fall back on old habits."

"Future work is needed to embed these changes into the UC system by incorporating antibiotic stewardship initiatives into local onboarding processes, annual mandatory education, audits, and national benchmarking," they concluded.
Jun 15 Pediatrics abstract


England's NHS set to begin subscription-style payments for 2 antibiotics

England's National Health Service (NHS) announced yesterday it has agreed on reimbursement contracts for the two antibiotics selected for its pioneering, subscription-style payment model, and will soon make them available to patients.

Under the first-of-its-kind payment model, the NHS will pay an annual fee of up to £10 million ($12.4 million US) a year for up to 10 years for access to cefiderocol and ceftazidime-avibactam, manufactured by Shionogi and Pfizer, respectively. The hope is that paying an annual fee to the drugmakers based on the public health value of the two drugs, rather than reimbursing them based on the quantity of antibiotics sold, will incentivize funding for research into new antibiotics.

Although the two antibiotics are critical for patients with severe, multidrug-resistant infections like sepsis, hospital- or ventilator-acquired pneumonia, and bloodstream infections, they are used sparingly to avoid development of resistance, and the people who need them are relatively few. The low sales and lack of return on investment for these and other new antibiotics have led many pharmaceutical companies and investors to abandon antibiotic development, resulting in a weak pipeline of new products.

NHS and the UK National Institute for Health and Care Excellence selected cefiderocol and ceftazidime-avibactam as the first antibiotics to be bought through the pilot program in December 2020. The NHS says around 1,700 patients a year with severe bacterial infections will be eligible for the drugs, and the agreement ensures they will be used only when necessary.

"This world-leading agreement not only provides a template for other countries to follow, incentivising antimicrobial drug innovation globally, as we collectively deal with this threat to modern medicine and public health, but also gives new hope to thousands of patients who previously had no treatment options left," NHS Chief Executive Amanda Pritchard said in a press release.
Jun 15 NHS press release


Study: Not-susceptible urinary tract infections costlier, higher-impact

A study of electronic medical record data found that female patients with uncomplicated urinary tract infections (uUTIs) caused by not-susceptible urinary bacteria had higher healthcare costs and were more likely to develop a more serious infection compared with patients with susceptible bacteria, researchers reported this week in Antimicrobial Resistance and Infection Control.

Using data from an integrated delivery network that serves patients in mid-Atlantic states, researchers analyzed all female patients ages 12 years and older who received an antibiotic for a uUTI from July 2016 through March 2020 and had at least one urine culture within 5 days of diagnosis. The primary outcome was the difference in healthcare use and costs among patients with susceptible versus not-susceptible isolates during the 6 months after the primary diagnosis. Secondary outcomes included hospital and emergency department visits and the probability of progressing to a complicated urinary tract infection (cUTI).

A total of 2,018 women were included in the final analysis, with an average age of 44 years for both groups. The most commonly prescribed antibiotics were nitrofurantoin (60.8%), trimethoprim-sulfamethoxazole (19.4%), and ciprofloxacin (14.6%).

In the 6 months post-index uUTI event, patients with not-susceptible isolates had significantly higher numbers of prescriptions (+ 1.41) and UTI-specific prescriptions (+ 0.26) versus patients with susceptible isolates. They also had a higher probability of all-cause outpatient (+ 6.1%), UTI-related outpatient (+ 3.7%), and all-cause inpatient (+ 1.4%) visits. The predicted probability of disease progression to cUTI was more than double for patients with not-susceptible versus susceptible isolates (odds ratio, 2.35; 95% confidence interval, 1.66 to 3.33). Over 6 months, patients with not-susceptible isolates had significantly higher all-cause costs (+ $426) and UTI-related costs (+ $157) than those with susceptible isolates.

The study authors say that, with antibiotic resistance increasing in community-acquired uUTIs in the United States, clinicians should transition away from purely empiric antibiotic prescribing.

"By treating these patients without specific knowledge of the pathogen or antibiotic susceptibility, there is a possibility that patients might be prescribed an antibiotic therapy to which their isolate is not-susceptible, leading to a higher probability of treatment failure and subsequent infections with antibiotic-resistant uropathogens," they wrote.
Jun 14 Antimicrob Resist Infect Control study

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