Study ties kids' MRSA skin infections to household colonization
A study of 150 households has found that recurrent methicillin-resistant Staphylococcus aureus skin and other soft-tissue infections (MRSA SSTIs) may be associated with persistent MRSA colonization of household members and contamination of environmental surfaces, US researchers reported yesterday in JAMA Pediatrics.
In the study, researchers from the Washington University School of Medicine in St. Louis and the University of Chicago investigated factors associated with persistent S aureus colonization and recurrent SSTI among 150 households with children with MRSA SSTIs, making a total of five quarterly visits over a 12-month period to conduct surveys and obtain swab samples from household members, pets, and environmental surfaces. Molecular testing was performed on all S aureus samples to identify the particular strain of the bacteria, and multivariable generalized mixed-effect logistic regression models were used to asses factors associated with persistent S aureus personal colonization, environmental contamination, and interval SSTI.
Of 540 participants who completed all five samplings, 213 (39%) were persistently colonized with S aureus, most often in the nostrils and with the same strain that infected the index patient at enrollment. Nine pets (8%) were persistently colonized with S aureus. Participants reporting interval intranasal mupirocin application were less likely to experience persistent colonization (odds ratio [OR], 0.44; 95% credible interval [CrI], 0.30 to 0.66), whereas increasing strain-specific environmental contamination pressure was associated with increased individual persistent colonization (OR, 1.17; 95% CrI, 1.06 to 1.30). Strains with higher colonization pressure (OR, 1.47; 95% CrI, 1.25 to 1.71) and MRSA strains (OR, 1.57; 95% CrI, 1.16 to 2.19) were more likely to persist.
Seventy-six index patients (53%) and 101 household contacts (19%) reported interval SSTIs. Individuals persistently colonized with MRSA (OR, 1.56; 95% CrI, 1.17 to 2.11), those with a history of SSTI (OR, 2.55; 95% CrI, 1.88 to 3.47), and index patients (OR, 1.54; 95% CrI, 1.07 to 2.23) were more likely to report an interval SSTI.
"Our analyses suggest that long-term eradication and SSTI prevention measures should be targeted at both the personal and the household levels, pairing personal decolonization with environmental hygiene interventions associated with reduced contamination," the authors wrote.
Mar 30 JAMA Pediatr abstract
Global flu surveillance shows declining flu, with some ILI rises
Flu activity in many parts of the Northern Hemisphere continues to decline, though influenza-like illness (ILI) markers remained high or rose in some countries, the World Health Organization (WHO) said yesterday in its latest global flu update.
The high and rising levels of ILI in the face of declining flu positive tests probably reflects the COVID-10 pandemic, though the report did not address that connection. The WHO did say, however, that during the reporting period, which covers the first half of March, several countries tested routine flu surveillance specimens, and some found COVID-19 positives, a practice it encourages if resources are available.
North American countries, including some in Europe saw declining rates of tests positive for flu but increased ILI levels. Flu activity was low in several parts of the world, for example, in Central Asia and Western Asia. In East Asia, both flu positives and ILI levels declined.
In temperate parts of the Southern Hemisphere, flu is still at interseasonal levels, though in some parts of Australia, emergency department visits for respiratory symptoms increased and were at levels higher than expected for this time of year. In South Africa, detections of 2009 H1N1 flu were up slightly.
Globally, of respiratory samples that tested positive for flu, 72.1% were influenza A. Of the subtyped influenza A viruses, 77.7% were 2009 H1N1.
Mar 30 WHO global flu update