The World Health Organization (WHO) has set an August 14 date for a meeting of its emergency committee to discuss developments regarding a surge of mpox activity in Africa and if the situation warrants a public health emergency of international concern (PHEIC).

Some of the outbreaks in Africa involve the novel clade 1b strain that emerged in the Democratic Republic of the Congo (DRC), which has been battling a severe outbreak since 2022. Some of the DRC's neighboring countries, which hadn't confirmed any mpox cases before, are now reporting cases. Also, the parent clade 1 virus is spreading in the DRC and two other countries, and the global clade 2 mpox strain is fueling outbreaks in some of the DRC's regions and in other African countries.

Health officials are working to better understand the spread patterns and if there are differences in transmissibility and disease severity among the clades. The DRC's outbreak has been marked by sexual spread for the first time in the African region, along with household contact and suspected contributions from respiratory transmission.

For now, the countries lack vaccines and treatments to battle the virus.

Second emergency committee for mpox in 2 years

The upcoming emergency committee meeting will be the second to grapple with mpox. In June 2022, the WHO convened an emergency committee to address challenges with the international spread of the clade 2 virus and said the situation didn't at that point warrant a PHEIC. A month later, the group met again and wasn't able to reach a consensus, but WHO Director-General Tedros Adhanom Ghebreyesus, PhD, considered their advice and declared a PHEIC. 

After the group met for the fifth time in May 2023 amid a steady decline in clade 2 cases, Tedros accepted the group's recommendation that the situation no longer constituted a PHEIC and that long-term challenges could be best handled with sustained response efforts.

A new study in Open Forum Infectious Diseases analyzed the clinical features of and outcomes of pediatric and adult hospitalized COVID patients at five US sites, and found that teens were at greatest risk for severe disease among all children, and those 50 to 64 years old were at greatest risk among all adults.

The study took place from March 2020 to March 2023 and included 1,560 hospitalized COVID-19 patients. Researchers calculated adjusted odds ratios (aORs) of clinical outcomes for children versus adults, younger kids compared to teens (12 to 17 years), and for older adults compared to young adults (22 to 49 years), the authors said. 

In total the study included 885 patients ages 0 to 21 years and 675 participants ages 22 to 105 years. 

Overall, children were less commonly vaccinated compared to adults ages 21 and older (14.3% vs 34.5%), and more commonly infected with the Omicron variant (49.5% vs 26.1%). Children also had fewer comorbidities than adults did.

Children had lower odds of supplemental oxygen

Children had much lower odds of receiving supplemental oxygen (aOR, 0.57; 95% confidence interval [CI], 0.35 to 0.92) and death (aOR, 0.01; 95% CI, <0.01 to 0.58) compared to adults. However, children had increased adjusted odds of receiving high-flow oxygen (2.18; 95% CI, 1.29 to 3.67) compared to adults, which the authors explained may be because this modality is more commonly used to support ventilation in the pediatric population.

Interestingly, adults aged 50-64 years had the highest odds of requiring mechanical ventilation and ICU admission after adjusting for confounding variable.

"Overall, adolescents 12-17 years experienced the greatest disease severity among the pediatric age strata," the authors said. "Interestingly, adults aged 50-64 years had the highest odds of requiring mechanical ventilation and ICU admission after adjusting for confounding variables."

The authors said their study confirmed prior work that shows that overall children experience less severe COVID-19 disease compared to adults.

Pfizer today announced initial results from a trial of its respiratory syncytial virus (RSV) vaccine Abrysvo in immunocompromised adults, which suggest the vaccine is well tolerated and prompts a strong neutralizing antibody response following one dose.

In its announcement, the company said the results are part of an ongoing phase 3 trial to evaluate two doses of the vaccine in younger adults who are at higher risk of experiencing lower respiratory tract disease from RSV. The vaccine is currently approved for use in adults ages 60 and older and for pregnant women in their last trimester as a strategy for protecting newborns.

Four study groups

The study was designed to examine vaccination in four groups of immunocompromised adults: those with non–small cell lung cancer, those on hemodialysis due to end-stage renal disease, those with autoimmune inflammatory disorder receiving active immunomodulator therapy, and solid-organ transplant recipients. Of 203 participants, half were between ages 18 and 59. 

Though the company evaluated two doses, one 120-microgram dose generated a strong neutralizing response to both RSV subtypes across all age-groups. The safety profile was similar to findings from earlier trials. 

Pfizer said it will share the findings at upcoming scientific conferences, publish them in peer-reviewed scientific journals, and submit data to drug regulators.

A retrospective analysis of data on US hospital patients with infections caused by Enterobacterales and Pseudomonas aeruginosa found that inadequate empiric therapy (IET) and delayed use of newer antibiotics was associated with significantly worse outcomes, researchers reported late last week in BMC Infectious Diseases.

Using data from the Becton Dickinson (BD) Research Insights Database, researchers with BD and drugmaker Abbvie analyzed data on hospitalized adults with facility-reported antibiotic susceptibility results at 161 US facilities from 2018 through 2022. They defined IET as antibiotic therapy prescribed within 48 hours prior to culture collection until first susceptibility results that either did not cover the pathogen or to which the pathogen was found non-susceptible. Newer antibiotics included ceftazidime-avibactam, ceftolozane-tazobactam, cefiderocol, meropenem-vaborbactam, eravacycline, and imipenem-cilcastatin-relebactam.

Findings highlight need for faster susceptibility results

Among 229,320 Enterobacterales and 36,027 P aeruginosa susceptibility results, 1.7% and 16.8% were carbapenem non-susceptible (carb-NS), respectively. In patients with Enterobacterales infections, median time to first susceptibility result was longer for carb-NS than for carbapenem-susceptible infections (64 hours vs 48 hours), and IET was prescribed in 24% of hospital admissions. In multivariate analysis, IET was associated with significantly higher mortality (odds ratio [OR], 1.29; 95% confidence interval [CI], 1.16 to 1.43) and longer hospital stays (14.8 vs 13.3 days).

In P aeruginosa patients, IET was prescribed in 46.1% of admissions. Although mortality was numerically higher with IET, the difference was not statistically significant (OR, 1.17; 95% CI, 0.97 to 1.41), and there was no difference in hospital length of stay (LOS; 12.7 days for both).

Newer antibiotic therapy was prescribed for 703 Enterobacterales patients and 603 P aeruginosa admissions. Delayed start to newer antibacterial therapy was associated with significantly greater hospital mortality and significantly longer post-culture LOS for both groups.

"In conclusion, our study demonstrates that obtaining more rapid antibacterial susceptibility results may improve overall adequacy of empiric therapy and facilitate appropriate and timely use of newer antibacterials," the study authors wrote. "Given the importance of rapid diagnostics, the integration of key diagnostic tests with antibacterial stewardship programs should be considered."