Coxiella Burnetii Infections and Public Health Implications

Coxiella burnetii is a Gram-negative, obligate intracellular bacterium and the aetiological agent of Q fever, a zoonosis of global importance. Transmission typically occurs via inhalation of aerosolised bacteria shed by infected livestock, notably during parturition, leading to acute febrile illness, pneumonia or hepatitis in humans. A small proportion of cases progress to chronic disease, with endocarditis and vascular infections posing significant morbidity and mortality risks. Environmental stability of the pathogen enables long-range dispersal on dust particles and underlines the significance of geographic and climatic factors in outbreak dynamics. Surveillance and diagnosis rely on serology and molecular assays, yet underreporting persists due to nonspecific clinical presentation. Current vaccine strategies demonstrate efficacy but are limited by reactogenicity in sensitised individuals and restricted licensure, emphasising the need for safer immunoprophylaxis. Mitigation of Q fever demands a One Health approach integrating veterinary control measures, environmental monitoring and public health interventions. Recent advances in understanding bacterial phase variation, vaccine antigen selection and ecological transmission pathways offer promising avenues to refine prevention and reduce the global burden of this resilient pathogen.

Research from Nature Portfolio

Recent studies have uncovered a novel mechanism of lipopolysaccharide (LPS) phase variation in an attenuated Coxiella burnetii strain, revealing reversion–driven elongation of LPS structures and a corresponding increase in virulence in an animal model. A single base-pair mutation in the cbu0533 gene was identified as the driver of this reversal, restoring long-chain LPS and enhancing bacterial infectivity. This work highlights the molecular basis of phase variation and informs strategies to engineer safe, attenuated strains incapable of re-acquiring full virulence, thereby improving biosafety in laboratory and vaccine applications.

Coxiella Burnetii Infections and Public Health Implications publication trend

The graph below shows the total number of articles in coxiella burnetii infections and public health implications across all publications each year (not limited to Nature Index journals).

Technical terms

Coxiella burnetii: A Gram-negative intracellular bacterium causing Q fever in humans and animals.

Lipopolysaccharide (LPS): A complex glycolipid in the bacterial outer membrane critical for virulence and immune recognition.

Phase variation: The reversible alteration of bacterial surface structures that affects pathogenicity and immune evasion.

Small Cell Variant (SCV): A dormant, environmentally resistant form of Coxiella burnetii specialised for transmission.

Reactogenicity: The propensity of a vaccine or antigen to cause adverse inflammatory responses.

One Health: An integrated approach recognising the interconnectedness of human, animal and environmental health.

References

1. Natural reversion promotes LPS elongation in an attenuated Coxiella burnetii strain. Nature Communications (2024).
2. A Q fever outbreak among visitors to a natural cave, Bizkaia, Spain, December 2020 to October 2021. Eurosurveillance (2023).
3. Q fever immunology: the quest for a safe and effective vaccine. npj Vaccines (2023).
4. Airborne geographical dispersal of Q fever from livestock holdings to human communities: a systematic review and critical appraisal of evidence. BMC Infectious Diseases (2018).