Testing by a team of researchers with the Louis Stokes Cleveland VA Medical Center indicates that sporicidal disinfectants are more effective against the multidrug-resistant fungal pathogen Candida auris than quaternary-ammonium disinfectants, according to a study published today in Infection Control & Hospital Epidemiology.

For the study, the researchers tested 23 disinfectants used for cleaning and disinfecting surfaces at 57 healthcare facilities in 30 states. The products included chlorine- and peracetic acid–based disinfectants, which are sporicidal, and quaternary-ammonium and hydrogen peroxide–based disinfectants, which are not. To test their efficacy against C auris, the researchers used a three-part soil load containing isolates from four phylogenetic clades of C auris—including the drug-resistant clade 4 strain AR-0385—and a strain of Candida albicans and then cultured the soiled surfaces after they were treated.

The disinfectants were classified as effective if a greater than 5 log₁₀ reduction in C auris was achieved.

Cleaning and disinfection practices may not be sufficient to limit spread.

Overall, five chlorine-based disinfectants and the one peracetic acid–based disinfectant consistently reduced all the C auris and C albicans strains by 5 log₁₀ or more, as did three hydrogen peroxide–based cleaners. But the quaternary-ammonium disinfectants were largely ineffective. Only one product reduced C auris strains by more than 5 log₁₀, but it wasn't effective against the drug-resistant AR-0385 strain.

Current practices may not cut it

The study authors say that while real-world studies are needed, the findings are important because quaternary-ammonium disinfectants are widely used in US healthcare facilities, which have seen a dramatic increase C auris colonization and infection in recent years.

"The fact that many patients with C. auris are colonized and only detected through screening increases the likelihood that unrecognized cases may enter facilities where cleaning and disinfection practices may not be sufficient to limit spread," they wrote.

The risk of flu-related intensive care unit (ICU) admission was sevenfold higher in lower middle-income countries (LMICs) than in high-income countries (HICs), according to an analysis yesterday in the Journal of Infectious Diseases.

The Global Influenza Hospital Surveillance Network conducted the study, the first to evaluate years of global, patient-level data from hospitals to determine geographic differences in flu severity. The analysis included 15,660 patients admitted to 116 hospitals in 22 countries for flu from 2012 through 2019. Of all patients, 72.4% had influenza A, and 27.6% had influenza B.

"Given lack of routine testing for influenza, and the complex pathway by which influenza can exacerbate chronic conditions and lead to severe disease, influenza burden estimates remain uncertain, especially in data-poor settings," the authors wrote.

Comorbidities doubled the risk

After adjustment for patient-level covariates, the risk of flu-related ICU admission was sevenfold higher in LMICs than in HICs. Having two or more underlying medical conditions significantly heightened the likelihood of ICU admission, mechanical ventilation, and in-hospital death (adjusted odds ratios [aORs], 2.40, 2.58, and 1.66, respectively), while female sex was protective against death (aOR, 0.80).

Relative to patients aged 5 to 64 years, those 65 and older had double the odds of death (aOR, 2.18), and those younger than 5 had lower chances of ICU admission, mechanical ventilation, and death (aORs, 0.67, 0.67, and 0.17, respectively).

Delayed care-seeking in LMIC could contribute to the increased severity.

Admission during the 2017-18 flu season increased the risk of ICU admission, mechanical ventilation, and death (aORs, 1.62, 2.15, and 1.37, respectively). Infection with the influenza A H1N1 strain independently predicted ICU admission (aOR, 1.67), mechanical ventilation (aOR, 1.47), and death (aOR, 1.37) compared with influenza A H3N2.

The researchers noted that flu vaccination is generally less available in LMICs. "Moreover, differences in standards of care and/or lack of access to antivirals in LMIC are also a possible explanation," they wrote. "Delayed care-seeking in LMIC could contribute to the increased severity."

Pharmaceutical company Merck last week announced positive topline results from two phase 3 trials of its investigational 21-valent pneumococcal vaccine.

The vaccine, V116, covers the 21 serotypes of Streptococcus pneumoniae that are responsible for 85% of invasive pneumococcal disease in adults ages 65 years and older and includes 8 serotypes that represent adult pneumococcal disease and are not currently covered by pneumococcal vaccines. If approved, it would be the first pneumococcal conjugate vaccine specifically designed for adults.

In the STRIDE-3 trial, V116 demonstrated statistically significant immune responses 30 days post-vaccination when compared with the pneumococcal 20-valent conjugate vaccine (PCV20) in vaccine-naïve adults for serotypes common to both vaccines. In the STRIDE-6 trial, which evaluated the safety, tolerability, and immunogenicity of V116 in adults aged 50 and older who had received pneumococcal vaccination at least one year before enrollment, the vaccine demonstrated immunogenicity for all 21 serotypes. Both studies showed V116 had a safety profile that was comparable to the comparator vaccines (PCV13, PCV15, PCV20, and PPSV23).

Could represent an additional weapon

"Despite the availability of current pneumococcal conjugate vaccines, many adults remain vulnerable to pneumococcal disease, especially those who are older," Eliav Barr, MD, senior vice president, head of global clinical development, and chief medical officer at Merck Research Laboratories, said in a company press release. "These results support the potential for V116 to become an important new preventative option for adults, regardless of prior pneumococcal vaccination status, by expanding coverage to include eight serotypes not currently included in any licensed vaccine."

Despite the availability of current pneumococcal conjugate vaccines, many adults remain vulnerable to pneumococcal disease, especially those who are older.

Merck says it will make the trial results available to the scientific community in the near future. Four other phase 3 trials of V116 are still ongoing.