Related Experiment Video

Updated: Jul 6, 2026

Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae
09:12

Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae

Published on: January 17, 2014

The risk of infection after nasal colonization with Staphylococcus aureus

Nasia Safdar1, Elisa A Bradley

  • 1Section of Infectious Diseases, Department of Medicine, University of Wisconsin Medical School, Madison, WI 53792, USA. ns2@medicine.wisc.edu

The American Journal of Medicine
|April 1, 2008
PubMed
Abstract

Insights

Methicillin-resistant Staphylococcus aureus (MRSA) colonization increases infection risk fourfold compared to methicillin-susceptible S. aureus (MSSA). Effective MRSA eradication strategies are needed to mitigate this elevated risk.

Area of Science:

  • Infectious Diseases
  • Microbiology
  • Public Health

Background:

  • Staphylococcus aureus colonization, particularly nasal, is a precursor to invasive infections.
  • Distinguishing the infection risk between methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) colonization is crucial.

Purpose of the Study:

  • To systematically review and estimate the comparative risk of infection associated with MRSA versus MSSA colonization.
  • To clarify the magnitude of risk posed by MRSA colonization.

Main Methods:

  • Systematic review of ten observational studies including 1170 patients.
  • Meta-analysis using a random-effects model to calculate pooled odds ratios and 95% confidence intervals.
  • Data extracted on both MSSA and MRSA colonization and subsequent infection.

Main Results:

  • MRSA colonization was associated with a significant 4-fold increase in infection risk (OR 4.08, 95% CI 2.10-7.44).
  • Heterogeneity was observed across studies regarding patient populations, illness severity, and colonization detection methods.

Conclusions:

  • MRSA carriage presents a substantially higher risk for subsequent infection compared to MSSA.
  • Further research is essential to develop and validate methods for sustained MRSA eradication to reduce infection rates.

More Related Videos

Improved Enzyme Protection Assay to Study Staphylococcus aureus Internalization and Intracellular Efficacy of Antimicrobial Compounds06:36

Improved Enzyme Protection Assay to Study Staphylococcus aureus Internalization and Intracellular Efficacy of Antimicrobial Compounds

Published on: September 8, 2021

Related Concept Videos

Staphylococcal Skin Infections01:29

Staphylococcal Skin Infections

Staphylococcus aureus is a Gram-positive coccus that resides harmlessly on the skin and mucous membranes of healthy individuals. When the skin barrier is breached, it can shift from a commensal to an opportunistic pathogen. This transition is facilitated by surface adhesins, such as clumping factor B and S. aureus surface protein G (SasG), which bind to structural proteins, including loricrin and cytokeratin, in the damaged epidermis. Protein A, another key factor, binds the Fc region of...
Factors Affecting the Risk of Infection01:26

Factors Affecting the Risk of Infection

The hosts' susceptibility to infection depends on several factors. The integrity of the skin and mucous membranes helps protect the body against microbial attacks. When the skin is altered, the chance of infection, limb loss, and even death increases.
The integrity and count of the white blood cells help the body resist pathogens and fight infection. When impaired, it reduces the body's resistance to pathogens. The acidic pH levels of the gastrointestinal, genitourinary tracts, and skin create...
Microbiota of the Respiratory Tract01:29

Microbiota of the Respiratory Tract

The human respiratory tract, comprising the upper and lower segments, serves as a critical interface with the external environment. The upper respiratory tract (URT)—including the nostrils, sinuses, pharynx, and oropharynx—is heavily colonized by microbes, while the lower respiratory tract (LRT), composed of the larynx, trachea, bronchi, and lungs, was long thought to be sterile. However, recent molecular studies have revealed that the lungs are not devoid of microbes but act more like...
Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
Healthcare Associated Infections I: Iatrogenic, Exogenic and Endogenic01:26

Healthcare Associated Infections I: Iatrogenic, Exogenic and Endogenic

Healthcare-associated infections (HAIs) occur in a healthcare facility while a person receives care for another ailment. This category also includes work-related infections among healthcare staff.
HAIs significantly increase the cost of health care. Extended stays in healthcare institutions, increased disability, increased costs of medications, including specialized antibiotics, and prolonged recovery times add to the patient's expenses and the healthcare institution and funding bodies. Common...
Development of the Oral Microbiota01:28

Development of the Oral Microbiota

The establishment of the oral microbiome begins before birth, challenging the long-held belief that the fetal oral cavity is sterile. The presence of oral microbes such as Streptococcus and Fusobacterium in amniotic fluid suggests that microbial exposure may occur in utero, potentially through translocation from the maternal oral or gastrointestinal tract. This early colonization primes the neonatal immune system and sets the stage for subsequent microbial succession. Maternal health,...