Current Opinion in Infectious Diseases最新文献

Purpose of review: Cases of whooping cough (pertussis) have rebounded strongly from the very low incidence observed during the pandemic. This re-emergence is characterized by changes in epidemiology. Here we describe the importance of genomics to monitor and understand the drivers to these changes.

Recent findings: Changes in the genotype of strains isolated during recent outbreaks suggests that the pandemic disturbed the global Bordetella pertussis population structure. The emergence of dominant and antibiotic-resistant clones in China is of concern even though the source of antibiotic selection pressure on B. pertussis is unclear. A recent study illustrates how to use genomic data to go beyond just surveillance, inferring the relative fitness of genotypes and the identification of specific mutations distinguishing such lineages. Such approaches are required to understand the forces driving adaptation.

Summary: Pertussis is resurgent in many countries, involving changes in epidemiology and strong suggestions of strain adaptation. The continued use of vaccination, and design of new interventions, to control pertussis requires an understanding of these changes. Genomic analyses will be key to this, involving integration of more complete host and pathogen parameters than have been used to date.

Purpose of review: Since its emergence in 2020, the COVID-19 pandemic has created a global surge of survivors experiencing neurologic effects from SARS-CoV-2 infection. This review aims to provide an updated synthesis of the acute and chronic neurological manifestations of COVID-19, and to outline the current therapeutic strategies for these conditions.

Recent findings: Epidemiological studies have shown that COVID-19 patients with neurological symptoms during acute infection tend to have poorer hospital and functional outcomes. While the risk of adverse neurologic symptoms including cognitive dysfunction, headache, autonomic dysfunction, and chronic fatigue are thought to be greatest following infection with the original SARS-CoV-2 strain and its alpha variant, they remain prevalent after infection with subsequent less virulent strains as well. Some recent work has also found a link between SARS-CoV-2 and structural brain changes. However, ongoing trials show promising results for pharmacologic and nonpharmacologic treatments targeting the postacute neurological sequelae of COVID-19.

Summary: Lingering neurological manifestations after COVID-19 still pose considerable individual, healthcare system, and socioeconomic repercussions. Both preventive and multimodal treatment approaches are necessary to address these conditions. Further research is required to assess the lasting impacts of SARS-CoV-2 on the nervous system, particularly its potential contribution to the development of neurodegenerative diseases.

Purpose of review: Arthropod-borne viruses (arboviruses) represent a group of pathogens with increasing global relevance, some of which cause neuroinvasive disease. Transmitted by arthropod vectors and maintained by a variety of primary and amplifying hosts, epidemics are dependent on numerous environmental and anthropogenic factors. This review serves to highlight several important neuroinvasive arboviruses relevant to North America and discuss the neurologic presentations, diagnosis, outcomes, and future trends.

Recent findings: Recent shifts in the epidemiology and ecology of arboviruses in North America include the divergence of arboviruses such as dengue and chikungunya from dependence on enzootic cycles, the geographical expansion of Oropouche virus, and the increasing incidence of some established North American arboviruses such as Powassan virus. Accurate identification of the factors contributing to arboviral outbreaks is critical to improve preventive public health measures. Similarly, further elucidating the relevant pathogen and host factors that determine neuroinvasiveness, neurotropism, and neurovirulence will be key to the development of successful vaccines and targeted therapeutics.

Summary: Arboviruses are an important pathogen relevant to human disease. Familiarity with the presentations, diagnostic workup, treatment and preventive strategies, and expected course is critical for clinicians caring for these patients.

Purpose of review: Mycobacterium abscessus is the second most isolated nontuberculous mycobacterial (NTM) respiratory pathogen in United States. It is also among the most difficult to treat NTM respiratory pathogens. The purpose of this review is to highlight current opportunities and limitations in the management of M. abscessus pulmonary disease and ways to optimize therapy to avoid treatment choices that make management of these patients even more difficult.

Recent findings: The main themes of the manuscript emphasize recognition of M. abscessus drug resistance mechanisms and their implication for limiting M. abscessus treatment response. The dichotomy between favorable outcomes for macrolide-susceptible vs. macrolide-resistant M. abscessus isolates is discussed in detail as well as the limitations in our current in-vitro susceptibility testing of M. abscessus isolates.

Summary: Predictably favorable treatment outcomes for patients with M. abscessus pulmonary disease remain elusive. New antibiotic combinations offer promise but await clinical testing in prohibitively expensive trials. Some new approaches such as phage therapy have been introduced, but so far, none are universally available or reliably effective. Clinicians and patients are left to struggle with imperfect treatment strategies in the hopes that some will emerge to justify larger treatment trials.

Purpose of review: Evidence behind antibiotic duration while treating ventilator-associated pneumonia (VAP) remains unclear. There is a need to balance minimizing the development of antimicrobial resistance without compromising clinical outcomes given the high mortality.

Recent findings: Recent studies have suggested that shorter antibiotic courses, when individualized to clinical response, may be adequate for treating VAP without increasing the incidence of mortality or recurrence, regardless of pathogens. Moreover, shortening duration may reduce the risk of adverse events, including acute kidney injury.

Summary: Shortening the duration of antibiotic treatment for VAP, in the setting of appropriate clinical response, is a reasonable strategy to reduce costs and selective pressure driving antimicrobial resistance. This was demonstrated in the latest REGARD-VAP study, even among VAP patients with nonfermenting Gram-negative bacilli or carbapenem-resistant pathogens. Given the challenges in diagnosing VAP, such pragmatic approaches would be essential as part of overall antibiotic stewardship programmes. Further refinement to the criteria for antibiotic cessation may be possible.

Purpose of review: The prevalence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) in skin and soft tissue infections (SSTI) has significantly changed in recent decades. We conducted a literature review to determine whether this microorganism, which became increasingly common as a cause of SSTI in the 2000s, still plays a significant role in these infections today.

Recent findings: Over the past 30 years, there has been a pattern of increase and then decrease in these infections. The highest frequency was observed in the United States, to the extent that guidelines recommended empirical antibiotic treatment for this pathogen in SSTI. Clone USA300 is the primary causative agent in the United States. In Europe, SSTI are much less common than in the United States, and the presence of this clone has been significantly lower. A decrease in the frequency of SSTI and CA-MRSA has been observed in developed countries. However, the spread of specific clones in Latin America, Asia and Africa highlights the need for rigorous global surveillance.

Summary: In recent years, the prevalence of CA-MRSA SSTI has decreased in developed countries. However, globalisation, immigration and intercontinental travel have favoured the spread of some clones with epidemic potential. It remains to be seen whether the current lower frequency will be maintained or whether these clones will give rise to a new wave.

Purpose of review: Arboviral infections caused by Dengue, Zika, and Chikungunya viruses continue to pose a significant global health threat, particularly in endemic regions. This review is timely because of the increasing prevalence of these infections, driven by factors such as urbanization and climate change. Dermatological manifestations of these viruses are crucial for early diagnosis, especially given the overlap in symptoms, which can complicate differential diagnosis.

Recent findings: Recent studies emphasize the importance of mucocutaneous symptoms in diagnosing arboviral infections. In Dengue, distinctive rashes like the 'islands of white in a sea of red' and hemorrhagic skin manifestations have been key diagnostic features. Zika is marked by a pruritic maculopapular rash and nonpurulent conjunctivitis, whereas Chikungunya often results in persistent rashes, desquamation, and hyperpigmentation, particularly on the face. Emerging research highlights the skin's role as both a primary infection site and an immune mediator in these viral diseases, offering new insights into their pathophysiology and potential therapeutic targets.

Summary: The unique dermatological profiles of Dengue, Zika, and Chikungunya are critical for guiding clinical diagnosis and treatment, especially in resource-limited settings. Understanding these cutaneous manifestations can improve early recognition, particularly in differentiating between these viruses in co-endemic areas. Future research may uncover novel therapeutic strategies by focusing on the interaction between these viruses and the skin's immune responses.

Purpose of review: To discuss recent findings on the global burden of respiratory tract infections in underprivileged populations, highlighting the critical role of socioeconomic factors in the incidence and severity of these diseases, with a particular focus on health disparities affecting Indigenous communities.

Recent findings: Pulmonary tuberculosis and lower respiratory tract infections, particularly those caused by Streptococcus pneumoniae and respiratory syncytial virus (RSV), continue to disproportionally impact populations in low-income countries and Indigenous communities worldwide. Indigenous children <5 years old bear the highest global burden of RSV infection, reflecting persistent social inequalities between Indigenous and non-Indigenous populations. Repeated episodes of acute pneumonia during childhood significantly contribute to the high prevalence of chronic respiratory diseases among Indigenous populations. The widespread occurrence of bronchiectasis in these communities is closely linked to adverse socioeconomic conditions.

Summary: Significant disparities in the incidence and severity of lower respiratory tract infections between affluent and impoverished populations are driven by socioeconomic inequalities. Vaccinating vulnerable population groups with newly developed vaccines has the potential to prevent infections caused by pathogens such as S. pneumoniae and RSV. However, global access to these vaccines and monoclonal antibodies remains limited due to their high costs.