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To describe the infection control preparedness measures undertaken for coronavirus disease (COVID-19) due to SARS-CoV-2 (previously known as 2019 novel coronavirus) in the first 42 days after announcement of a cluster of pneumonia in China, on December 31, 2019 (day 1) in Hong Kong.
A bundled approach of active and enhanced laboratory surveillance, early airborne infection isolation, rapid molecular diagnostic testing, and contact tracing for healthcare workers (HCWs) with unprotected exposure in the hospitals was implemented. Epidemiological characteristics of confirmed cases, environmental samples, and air samples were collected and analyzed.
From day 1 to day 42, 42 of 1,275 patients (3.3%) fulfilling active (n = 29) and enhanced laboratory surveillance (n = 13) were confirmed to have the SARS-CoV-2 infection. The number of locally acquired case significantly increased from 1 of 13 confirmed cases (7.7%, day 22 to day 32) to 27 of 29 confirmed cases (93.1%, day 33 to day 42; P < .001). Among them, 28 patients (66.6%) came from 8 family clusters. Of 413 HCWs caring for these confirmed cases, 11 (2.7%) had unprotected exposure requiring quarantine for 14 days. None of these was infected, and nosocomial transmission of SARS-CoV-2 was not observed. Environmental surveillance was performed in the room of a patient with viral load of 3.3 × 106 copies/mL (pooled nasopharyngeal and throat swabs) and 5.9 × 106 copies/mL (saliva), respectively. SARS-CoV-2 was identified in 1 of 13 environmental samples (7.7%) but not in 8 air samples collected at a distance of 10 cm from the patient’s chin with or without wearing a surgical mask.
Appropriate hospital infection control measures was able to prevent nosocomial transmission of SARS-CoV-2.
Understanding the pattern of middle-ear cholesteatoma becomes pertinent with the rise of endoscopic surgery as surgeons decide on the optimal approach to visualise and extirpate disease. With modifications to the Telmesani attic–tympanum–mastoid staging system, this study aimed to evaluate the commonest patterns of middle-ear cholesteatoma and their implications for surgical approach.
A retrospective study was conducted in a single tertiary institution in Singapore. All patients undergoing cholesteatoma surgery between January 2012 and June 2015 were included. Staging of cholesteatoma was based on clinical assessment corroborated by radiological findings.
Out of the 55 ears included, 98.2 per cent had cholesteatoma involving the attic. The disease extended into the mastoid antrum and beyond in 43 cases (78.2 per cent). The facial recess and/or sinus tympanum was affected in 26 cases (47.3 per cent).
The majority of cholesteatoma cases present with extensive attic disease and significant mastoid involvement. In these cases, endoscopes may be best suited to adjunctive rather than exclusive use in surgery.
Seasonal influenza virus epidemics have a major impact on healthcare systems. Data on population susceptibility to emerging influenza virus strains during the interepidemic period can guide planning for resource allocation of an upcoming influenza season. This study sought to assess the population susceptibility to representative emerging influenza virus strains collected during the interepidemic period. The microneutralisation antibody titers (MN titers) of a human serum panel against representative emerging influenza strains collected during the interepidemic period before the 2018/2019 winter influenza season (H1N1-inter and H3N2-inter) were compared with those against influenza strains representative of previous epidemics (H1N1-pre and H3N2-pre). A multifaceted approach, incorporating both genetic and antigenic data, was used in selecting these representative influenza virus strains for the MN assay. A significantly higher proportion of individuals had a ⩾four-fold reduction in MN titers between H1N1-inter and H1N1-pre than that between H3N2-inter and H3N2-pre (28.5% (127/445) vs. 4.9% (22/445), P < 0.001). The geometric mean titer (GMT) of H1N1-inter was significantly lower than that of H1N1-pre (381 (95% CI 339–428) vs. 713 (95% CI 641–792), P < 0.001), while there was no significant difference in the GMT between H3N2-inter and H3N2-pre. Since A(H1N1) predominated the 2018–2019 winter influenza epidemic, our results corroborated the epidemic subtype.
Dislocation of the cochlear implant magnet is an uncommon but recognised complication of magnetic resonance imaging in a patient with a cochlear implant.
This paper reports a case of cochlear implant magnet dislocation despite head bandaging. The patient subsequently underwent endoscopic repositioning of the magnet under general anaesthesia. The cochlear implant system was tested intra-operatively and confirmed to be functioning. The patient was well at follow up and the small wound healed well with no complications.
This report presents the endoscopic technique as a viable minimally invasive surgical approach to address cochlear implant magnet dislocation.
Multidrug-resistant organisms (MDROs) are increasingly reported in residential care homes for the elderly (RCHEs). We assessed whether implementation of directly observed hand hygiene (DOHH) by hand hygiene ambassadors can reduce environmental contamination with MDROs.
From July to August 2017, a cluster-randomized controlled study was conducted at 10 RCHEs (5 intervention versus 5 nonintervention controls), where DOHH was performed at two-hourly intervals during daytime, before meals and medication rounds by a one trained nurse in each intervention RCHE. Environmental contamination by MRDOs, such as methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Acinetobacter species (CRA), and extended-spectrum β-lactamse (ESBL)–producing Enterobacteriaceae, was evaluated using specimens collected from communal areas at baseline, then twice weekly. The volume of alcohol-based hand rub (ABHR) consumed per resident per week was measured.
The overall environmental contamination of communal areas was culture-positive for MRSA in 33 of 100 specimens (33%), CRA in 26 of 100 specimens (26%), and ESBL-producing Enterobacteriaceae in 3 of 100 specimens (3%) in intervention and nonintervention RCHEs at baseline. Serial monitoring of environmental specimens revealed a significant reduction in MRSA (79 of 600 [13.2%] vs 197 of 600 [32.8%]; P<.001) and CRA (56 of 600 [9.3%] vs 94 of 600 [15.7%]; P=.001) contamination in the intervention arm compared with the nonintervention arm during the study period. The volume of ABHR consumed per resident per week was 3 times higher in the intervention arm compared with the baseline (59.3±12.9 mL vs 19.7±12.6 mL; P<.001) and was significantly higher than the nonintervention arm (59.3±12.9 mL vs 23.3±17.2 mL; P=.006).
The direct observation of hand hygiene of residents could reduce environmental contamination by MDROs in RCHEs.
To study the association between gastrointestinal colonization of carbapenemase-producing Enterobacteriaceae (CPE) and proton pump inhibitors (PPIs).
We analyzed 31,526 patients with prospective collection of fecal specimens for CPE screening: upon admission (targeted screening) and during hospitalization (opportunistic screening, safety net screening, and extensive contact tracing), in our healthcare network with 3,200 beds from July 1, 2011, through December 31, 2015. Specimens were collected at least once weekly during hospitalization for CPE carriers and subjected to broth enrichment culture and multiplex polymerase chain reaction.
Of 66,672 fecal specimens collected, 345 specimens (0.5%) from 100 patients (0.3%) had CPE. The number and prevalence (per 100,000 patient-days) of CPE increased from 2 (0.3) in 2012 to 63 (8.0) in 2015 (P<.001). Male sex (odds ratio, 1.91 [95% CI, 1.15–3.18], P=.013), presence of wound or drain (3.12 [1.70–5.71], P<.001), and use of cephalosporins (3.06 [1.42–6.59], P=.004), carbapenems (2.21 [1.10–4.48], P=.027), and PPIs (2.84 [1.72–4.71], P<.001) in the preceding 6 months were significant risk factors by multivariable analysis. Of 79 patients with serial fecal specimens, spontaneous clearance of CPE was noted in 57 (72.2%), with a median (range) of 30 (3–411) days. Comparing patients without use of antibiotics and PPIs, consumption of both antibiotics and PPIs after CPE identification was associated with later clearance of CPE (hazard ratio, 0.35 [95% CI, 0.17–0.73], P=.005).
Concomitant use of antibiotics and PPIs prolonged duration of gastrointestinal colonization by CPE.
Carbapenem-resistant Acinetobacter baumannii (CRAB) with diverse multilocus sequence typing emerged among our nursing home residents (6.5%) with a high background rate of MRSA (32.2%). Rectal swabs yielded a higher rate of CRAB detection than axillary or nasal swabs. Bed-bound status, use of adult diapers, and nasogastric tube were risk factors for CRAB colonization.
To assess the effectiveness of infection control preparedness for human infection with influenza A H7N9 in Hong Kong.
A descriptive study of responses to the emergence of influenza A H7N9.
A university-affiliated teaching hospital.
Healthcare workers (HCWs) with unprotected exposure (not wearing N95 respirator during aerosol-generating procedure) to a patient with influenza A H7N9.
A bundle approach including active and enhanced surveillance, early airborne infection isolation, rapid molecular diagnostic testing, and extensive contact tracing for HCWs with unprotected exposure was implemented. Seventy HCWs with unprotected exposure to an index case were interviewed especially regarding their patient care activities.
From April 1, 2013, through May 31, 2014, a total of 126 (0.08%) of 163,456 admitted patients were tested for the H7 gene by reverse transcription-polymerase chain reaction per protocol. Two confirmed cases were identified. Seventy (53.8%) of 130 HCWs had unprotected exposure to an index case, whereas 41 (58.6%) and 58 (82.9%) of 70 HCWs wore surgical masks and practiced hand hygiene after patient care, respectively. Sixteen (22.9%) of 70 HCWs were involved in high-risk patient contacts. More HCWs with high-risk patient contacts received oseltamivir prophylaxis (P=0.088) and significantly more had paired sera collected for H7 antibody testing (P<0.001). Ten (14.3%) of 70 HCWs developed influenza-like illness during medical surveillance, but none had positive results by reverse transcription-polymerase chain reaction. Paired sera was available from 33 of 70 HCWs with unprotected exposure, and none showed seroconversion against H7N9.
Despite the delay in airborne precautions implementation, no patient-to-HCW transmission of influenza A H7N9 was demonstrated.
Nosocomial outbreaks of norovirus infection pose a great challenge to the infection control team.
Between November 1, 2009, and February 28, 2010, strategic infection control measures were implemented in a hospital network. In addition to timely staff education and promotion of directly observed hand hygiene, reverse-transcription polymerase chain reaction for norovirus was performed as an added test by the microbiology laboratory for all fecal specimens irrespective of the request for testing. Laboratory-confirmed cases were followed up by the infection control team for timely intervention. The incidence of hospital-acquired norovirus infection per 1,000 potentially infectious patient-days was compared with the corresponding period in the preceding 12 months, and the incidence in the other 6 hospital networks in Hong Kong was chosen as the concurrent control. Phylogenetic analysis of norovirus isolates was performed.
Of the 988 patients who were tested, 242 (25%) were positive for norovirus; 114 (47%) of those 242 patients had norovirus detected by our added test. Compared with the corresponding period in the preceding 12 months, the incidence of hospital-acquired norovirus infection decreased from 131 to 16 cases per 1,000 potentially infectious patient-days (P < .001 ), although the number of hospital-acquired infections was low in both the study period (n = 8) and the historical control periods (n = 11). The incidence of hospital-acquired norovirus infection in our hospital network (0.03 cases per 1,000 patient-days) was significantly lower than that of the concurrent control (0.06 cases per 1,000 patient-days) (P = .015). Forty-three (93%) of 46 norovirus isolates sequenced belonged to the genogroup II.4 variant.
Strategic infection control measures with an added test maybe useful in controlling nosocomial transmission of norovirus.
Patients with nasopharyngeal carcinoma may have residual cervical lymphadenopathy after definitive treatment of the primary tumour and regional cervical nodal disease. Whether such lymphadenopathy truly represents persistent disease is unclear. There are few published studies addressing this clinical problem.
We retrospectively and systematically reviewed the clinical records of 12 patients with nasopharyngeal carcinoma who had presented to a tertiary academic hospital, over an 11-year period, with suspected persistent cervical nodal disease after definitive radiotherapy or concurrent chemoradiotherapy. Findings on fine needle aspiration cytology and computed tomography scanning were correlated with final histopathological results.
The incidence of negative neck dissection was 41.7 per cent. The positive and negative predictive values of fine needle aspiration cytology in identifying disease were 100 and 42.9 per cent, respectively. Computed tomography scanning had a positive predictive value of 58.3 per cent in identifying disease.
In patients treated definitively for nasopharyngeal carcinoma, residual cervical lymphadenopathy may not represent persistent disease. Head and neck surgeons involved in the management of these patients should bear in mind the current limitations of fine needle aspiration cytology and computed tomography in confirming the diagnosis pre-operatively. Salvage neck dissection may over-treat some of these patients.
We report a case of otogenic fungal pachymeningitis in a diabetic patient who presented with multiple cranial nerve palsies and nasopharyngeal swelling.
We present a case report, we describe the investigations, management and clinical course of fungal pachymeningitis, and we present a review of the world literature on fungal and non-fungal pachymeningitis.
To our knowledge, this is the first report of fungal pachymeningitis with magnetic resonance imaging features suggestive of nasopharyngeal carcinoma. It is also the first reported case with aspergillus cultured from both a dural biopsy and the ear canal.
Fungal pachymeningitis is a rare condition which may present to otorhinolaryngologists. Its clinical and radiological findings can be confused with those of nasopharyngeal carcinoma; fungal pachymeningitis should thus be included in the differential diagnosis of nasopharyngeal carcinoma.
To determine the prevalence of tonsillar actinomycetes colonization in patients with and without recurrent tonsillitis and to study the association of this condition with recurrent tonsillitis and tonsillar hypertrophy.
Study design and setting:
A retrospective study of 834 patients who had undergone tonsillectomy for recurrent tonsillitis (group A) and for sleep-disordered breathing without a history of recurrent tonsillitis (group B).
The prevalence of tonsillar actinomycetes colonization was higher in patients who had undergone tonsillectomy for sleep-disordered breathing (44.1 per cent) than in patients who had undergone tonsillectomy for recurrent tonsillitis (33.3 per cent). The prevalence did not differ by sex or age of patient, although the occurrence rate was higher in the adult compared with the paediatric population. There was no statistically significant difference between the mean size of the tonsils removed in the two groups, and actinomycetes colonization did not affect tonsil size. Histopathological analysis of resected tonsils did not show active tissue infection.
The presence of actinomyces does not indicate active disease. We are of the opinion that, although actinomyces colonization is more prevalent in patients with sleep-disordered breathing, it does not contribute to tonsillar hypertrophy nor to recurrent tonsillitis.
Conductive-polymer coated fabrics have been investigated as intelligent materials in the past years. In this paper, a flexible fabric strain sensor coated with polypyrrole is reported, which is featured with high sensitivity, good stability and large deformation. It is fabricated by chemical vapor deposition at low temperature. The effects of temperature, humidity, acid and alkaline medium have been assessed. The conductivity-strain tests reveal the sensor exhibits a high strain sensitivity of ~160 for a deformation as large as 50%, while its good stability is indicated by a small loss of conductivity after the thermal and humidity aging tests, and supported by the slight change in conductivity and sensitivity over a storage of eighteen months. The acid and alkaline solution mainly decreased their initial conductivity but have the slight effect to their sensitivity. The flexible fabric strain sensor is expected to be a promising “soft” smart material in the smart garment, wearable hardware and biomedical applications.
Myxofibrosarcoma was originally described as the myxoid variant of malignant fibrous histiocytoma (MFH). It is uncommon in the head and neck region. We hereby report a case of myxofibrosarcoma in the sphenoid sinuses. The diagnostic and management difficulties are discussed. Close collaboration between surgeon, radiologist, histopathologist and clinical oncologist in making accurate diagnosis and appropriate management of this rare tumour are emphasized.
A novel MEMS technology using multi-layer poly-silicon (poly-Si) is proposed. The poly-Si film is formed from the new Nickel-Induced-Lateral-Crystallization (NILC) method and has very large grain (>10νm) and near crystal quality. 700 nm thermal oxide was grown on a Si wafer. 100 nm LPCVD amorphous Si was deposited and followed by a 50 Å Ni deposition. The a-Si was crystallized at 550°C for 65 hours and subsequent 800°C for 2 hours to form the first (lower) NILC poly-Si layer. N-channel TFTs were fabricated on the NILC polysilicon layer. The process was repeated and a second (upper) polysilicon layer and TFTs were formed on top of the first polysilicon layer.
The lower polysilicon has slightly larger grains and better material quality. Thin-film- transistors (TFT) fabricated on the 3-dimensional (3-D) poly-Si layers have I-V characteristics similar to (>40%) silicon-on-insulator TFTs. While TFTs on lower layer have better mobility and device properties, TFTs on upper layer have better uniformity. The accumulated heating and other effects have also been studied.
When molten Pd40.5Ni40.5P19 is undercooled way below its liquidus Tl, liquid state spinodal decomposition is observed. Crystallization of this system is particularly interesting because it has plenty of interfaces. The microstructure of an as-crystallized specimen can be divided into four regions, namely, A: random spinodal; B: aligned and elongated spinodal; C: coarsened spinodal and island structure; and D: rod structure and ternary eutectics. The origin of these different microstructures is discussed.