An outbreak of infections caused by non-typeable Haemophilus influenzae in an extended care facility

Effective infection prevention and control measures in long-term care facilities in non-outbreak and outbreak settings: a systematic literature review

BACKGROUND

Healthcare-associated infections in long-term care are associated with substantial morbidity and mortality. While infection prevention and control (IPC) guidelines are well-defined in the acute care setting, evidence of effectiveness for long-term care facilities (LTCF) is missing. We therefore performed a systematic literature review to examine the effect of IPC measures in the long-term care setting.

METHODS

We systematically searched PubMed and Cochrane libraries for articles evaluating the effect of IPC measures in the LTCF setting since 2017, as earlier reviews on this topic covered the timeframe up to this date. Cross-referenced studies from identified articles and from mentioned earlier reviews were also evaluated. We included randomized-controlled trials, quasi-experimental, observational studies, and outbreak reports. The included studies were analyzed regarding study design, type of intervention, description of intervention, outcomes and quality. We distinguished between non-outbreak and outbreak settings.

RESULTS

We included 74 studies, 34 (46%) in the non-outbreak setting and 40 (54%) in the outbreak setting. The most commonly studied interventions in the non-outbreak setting included the effect of hand hygiene (N = 10), oral hygiene (N = 6), antimicrobial stewardship (N = 4), vaccination of residents (N = 3), education (N = 2) as well as IPC bundles (N = 7). All but one study assessing hand hygiene interventions reported a reduction of infection rates. Further successful interventions were oral hygiene (N = 6) and vaccination of residents (N = 3). In outbreak settings, studies mostly focused on the effects of IPC bundles (N = 24) or mass testing (N = 11). In most of the studies evaluating an IPC bundle, containment of the outbreak was reported. Overall, only four articles (5.4%) were rated as high quality.

CONCLUSION

In the non-outbreak setting in LTCF, especially hand hygiene and oral hygiene have a beneficial effect on infection rates. In contrast, IPC bundles, as well as mass testing seem to be promising in an outbreak setting.

Bacterial composition of nasal discharge in children based on highly accurate 16S rRNA gene sequencing analysis

Nasopharyngeal colonization by bacteria is a prerequisite for progression to respiratory disease and an important source of horizontal spread within communities. We aimed to perform quantitative analysis of the bacterial cells and reveal the microbiota of the nasal discharge in children at the species level based on highly accurate 16S rRNA gene sequencing. This study enrolled 40 pediatric patients with rhinorrhea. The bacterial cells in the nasal discharge were counted by epifluorescence microscopic analysis. The microbiota was analyzed by using the 16S rRNA gene clone library sequencing method. We demonstrated that a high abundance (median 2.2 × 10⁷ cells/mL) of bacteria was contained in the nasal discharge of children. Of the 40 samples, 37 (92.5%) were dominated by OTUs corresponding to Haemophilus aegyptius/influenzae, Moraxella catarrhalis/nonliquefaciens, or Streptococcus pneumoniae. These samples showed higher cell abundance and lower alpha diversity than the remaining three samples in which the other bacteria coexisted. In addition, 12 sequences with low homology to type strains were considered as previously unknown bacterial lineages. In conclusion, the nasal discharge of most young children contains a large amount of respiratory pathogens and several unknown bacteria, which could not only cause endogenous infection but also be a source of transmission to others.

A systematic review on the causes of the transmission and control measures of outbreaks in long-term care facilities: Back to basics of infection control

BACKGROUND

The unique characteristics of long-term care facilities (LTCFs) including host factors and living conditions contribute to the spread of contagious pathogens. Control measures are essential to interrupt the transmission and to manage outbreaks effectively.

AIM

The aim of this systematic review was to verify the causes and problems contributing to transmission and to identify control measures during outbreaks in LTCFs.

METHODS

Four electronic databases were searched for articles published from 2007 to 2018. Articles written in English reporting outbreaks in LTCFs were included. The quality of the studies was assessed using the risk-of-bias assessment tool for nonrandomized studies.

FINDINGS

A total of 37 studies were included in the qualitative synthesis. The most commonly reported single pathogen was influenza virus, followed by group A streptococcus (GAS). Of the studies that identified the cause, about half of them noted outbreaks transmitted via person-to-person. Suboptimal infection control practice including inadequate decontamination and poor hand hygiene was the most frequently raised issue propagating transmission. Especially, lapses in specific care procedures were linked with outbreaks of GAS and hepatitis B and C viruses. About 60% of the included studies reported affected cases among staff, but only a few studies implemented work restriction during outbreaks.

CONCLUSIONS

This review indicates that the violation of basic infection control practice could be a major role in introducing and facilitating the spread of contagious diseases in LTCFs. It shows the need to promote compliance with basic practices of infection control to prevent outbreaks in LTCFs.

Intensive Patient Treatment

Intensive care units (ICUs) are treating hospital’s poorest patients that need medical assistance during the most extreme period of their life. Intensive patients are treated with extensive invasive procedures, which may cause a risk of hospital infections in 10–30% of the cases. More than half of these infections can be prevented. The patients are often admitted directly from outside the hospital or from abroad with trauma after accidents, serious heart and lung conditions, sepsis and other life-threatening diseases. Infection or carrier state of microbes is often unknown on arrival and poses a risk of transmission to other patients, personnel and the environment. Patients that are transferred between different healthcare levels and institutions with unknown infection may be a particular risk for other patients. In spite of the serious state of the patients, many ICUs have few resources and are overcrowded and understaffed, with a lack of competent personnel. ICU should have a large enough area and be designed, furnished and staffed for a good, safe and effective infection control. The following chapter is focused on practical measures to reduce the incidence of infections among ICU patients.

Nosocomial Outbreak of Upper Respiratory Tract Infection With β-Lactamase-Negative Ampicillin-Resistant Nontypeable Haemophilus influenzae

OBJECTIVETo describe the epidemiologic features of an outbreak of an acute respiratory tract infection (ARI) caused by β-lactamase-negative ampicillin-resistant (BLNAR) nontypeable Haemophilus influenzae (NTHi) in an acute-care ward.DESIGNCross-sectional case-control study.SETTINGAn acute-care ward (ward A) in a general hospital of Kochi in western Japan.METHODSPatients who shared a room with an index patient and all staff in ward A were screened and followed from July 1 to August 31, 2015. Sputum or throat swab samples were collected from participants and tested by culture and polymerase chain reaction (PCR). The association between detected pathogens and ARI development among all participants was examined. A case-control study was conducted to identify risk factors for disease.RESULTSIn total, 78 participants, including the index patient, were enrolled. Of all participants, 27 (34.6%) developed mild respiratory symptoms during a 3-week period: 24 were diagnosed as upper respiratory tract infections, and 3 were diagnosed as lower respiratory tract infections. The presence of BLNAR NTHi was confirmed in 13 participants, and multilocus sequence typing demonstrated that these isolates belonged to sequence type 159. All isolates showed identical pulsed-field gel electrophoresis patterns. The presence of BLNAR NTHi was strongly associated with ARI development, whereas viruses were not associated with the disease. Multivariate analyses demonstrated that a history of contact with the index patient was independently associated with ARI caused by BLNAR NTHi.CONCLUSIONSBLNAR NTHi has the potential to cause upper respiratory tract infections among adults and to spread rapidly in hospital settings.Infect Control Hosp Epidemiol 2018;39:652-659.

Comparison of the first whole genome sequence of 'Haemophilus quentini' with two new strains of 'Haemophilus quentini' and other species of Haemophilus

Comparison of the genome of the Gram negative human pathogen Haemophilus quentini MP1 with other species of Haemophilus revealed that, although it is more closely related to Haemophilus haemolyticus than Haemophilus influenzae, the pathogen is in fact genetically distinct, a finding confirmed by phylogenetic analysis using the H. influenzae multilocus sequence typing genes. Further comparison with two other H. quentini strains recently identified in Canada revealed that these three genomes are more closely related than any other species of Haemophilus; however, there is still some sequence variation. There was no evidence of acquired antimicrobial resistance within the H. quentini MP1 genome nor any mutations within the DNA gyrase or topoisomerase IV genes known to confer resistance to fluoroquinolones, which has been previously identified in other H. quentini isolates. We hope by presenting the annotation and genetic comparison of the H. quentini MP1 genome it will aid the future molecular detection of this potentially emerging pathogen via the identification of unique genes that differentiate it from other species of Haemophilus.

Haemophilus influenzae serotype f endocarditis and septic arthritis

Haemophilus influenzae represents gram-negative coccobacilli which can cause endocarditis, meningitis, septicemia, pneumonia, septic arthritis. H.influenzae exists as encapsulated and unencapsulated (non-typeable) strains. Non-typeable H.influenzae are emerging pathogens especially in elderly population. We report a case of a 73 year old woman with bacteremia, endocarditis and septic arthritis due to H.influenzae serotype f. This case emphasizes the clinical features and the key elements of diagnosis and management of infections caused by non-typeable strains of H.influenzae.

Outbreak of a beta-lactam resistant non-typeable Haemophilus influenzae sequence type 14 associated with severe clinical outcomes

Background

During October 2011 several residents and staff members at a long-term care facility (LTCF) for elderly fell ill with respiratory symptoms. Several of the residents required hospitalization and one died. Non-typeable Haemophilus influenzae (NTHi) was identified as the causative pathogen.

Methods

A descriptive analysis of the outbreak and countermeasures was performed. For each identified bacterial isolate implied in the outbreak, standard laboratory resistance testing was performed, as well as molecular typing and phylogenetic analysis.

Results

The identified H. influenzae was beta-lactamase negative but had strikingly high MIC-values of ampicillin, cefuroxime and cefotaxime. All isolates displayed the same mutation in the ftsI gene encoding penicillin-binding protein (PBP) 3, and all but one were identified as sequence type 14 by Multilocus Sequence Typing (MLST). In total 15 individuals in connection to the LTCF; 8 residents, 6 staff members and one partner to a staff member were colonized with the strain.

Conclusion

This report illustrates the existence of non-typeable H. influenzae with high virulence, and furthermore emphasizes the importance of continuous surveillance of possible outbreaks in health care facilities and prompt measures when outbreaks occur.

Haemophilus influenzae infections in the H. influenzae type b conjugate vaccine era

The widespread use of Haemophilus influenzae type b (Hib) conjugate vaccines has nearly eradicated invasive Hib disease where the vaccines are used. This success was accompanied by a shift in capsular serotypes of invasive H. influenzae disease, with nontypeable strains replacing type b strains as the most common bloodstream isolate, but there is no convincing evidence of a true increase in the incidence of non-serotype b invasive infections. H. influenzae causes predominantly mucosal infections. The introduction of vaccines for otitis media and global shifts in antimicrobial susceptibility emphasize the importance of continued surveillance of H. influenzae colonization and disease patterns.

Radiological findings in acute Haemophilus influenzae pulmonary infection

OBJECTIVE

The aim of this study was to assess pulmonary thin-section CT findings in patients with acute Haemophilus influenzae pulmonary infection.

METHODS

Thin-section CT scans obtained between January 2004 and March 2009 from 434 patients with acute H. influenzae pulmonary infection were retrospectively evaluated. Patients with concurrent infection diseases, including Streptococcus pneumoniae (n=76), Staphylococcus aureus (n=58) or multiple pathogens (n=89) were excluded from this study. Thus, our study group comprised 211 patients (106 men, 105 women; age range, 16-91 years, mean, 63.9 years). Underlying diseases included cardiac disease (n=35), pulmonary emphysema (n=23), post-operative status for malignancy (n=20) and bronchial asthma (n=15). Frequencies of CT patterns and disease distribution of parenchymal abnormalities, lymph node enlargement and pleural effusion were assessed by thin-section CT.

RESULTS

The CT findings in patients with H. influenzae pulmonary infection consisted mainly of ground-glass opacity (n=185), bronchial wall thickening (n=181), centrilobular nodules (n=137) and consolidation (n=112). These abnormalities were predominantly seen in the peripheral lung parenchyma (n=108). Pleural effusion was found in 22 patients. Two patients had mediastinal lymph node enlargement.

CONCLUSION

These findings in elderly patients with smoking habits or cardiac disease may be characteristic CT findings of H. influenzae pulmonary infection.

[An outbreak of Hemophylus influenzae infection among residents in an insurance care facility for the elderly]

AIM

To study the epidemics of the hemophilus influenzae (HI) infection in the summer, 2005 among 46 residents in the second floor of our insurance care facility, Mam Cuore.

METHODS

The spreading pattern of HI infection, antibiotic susceptibility and serological identification of HI isolated from sputum culture were investigated, and underlying diseases, functional disorders, body weight, age, sex, ADL- and dementia-scores were compared among patients with the non-symptomatic group, HI infection and severe HI pneumonia groups.

RESULTS

Lower ADL and body weight were noted to suffer significantly more HI infection and severe pneumonia. Furthermore, stroke patients tended to suffer more HI infection. Dementia patients suffered significantly more severe pneumonia. Residents of rooms close to the room of original patient showed symptoms earlier than patients in more distant rooms. While the numbers of patients with HI infection were 15 (60%) and 10 (40%) before and after the first isolation of HI, 5 out of 15 patients (33%) and one out of 10 patients (10%) progressed to severe pneumonia, respectively. Although these results did not have statistical significance, they suggests that rapid assessment and therapy of HI infection tended to prevent aggravation. Non-typeable strains were detected and were all beta-lactamase nonproducing ampicillin resistant (BLNAR) without susceptibilities to cefaclor (CCL) and cefdinir (CFDN). Preceding the epidemic, an outbreak of the common cold syndrome was recognized.

CONCLUSION

Assessing elderly patients suspected of the HI infection, and organized management for treatment are essential to improving outcome.