Persistence of meticillin-resistant Staphylococcus aureus carriage in re-admitted patients.

A retrospective cohort study was conducted to investigate the duration and risk factors for persistence of meticillin-resistant Staphylococcus aureus (MRSA) colonization among known carriers who were re-admitted to hospital. MRSA carriage persisted in a high proportion of known carriers up to two years after their last date of discharge, and re-admission screening should be performed for at least this duration. A targeted screening approach should focus on older patients with a history of long inpatient stays, who are at higher risk of persistent carriage. Timely discharge planning is important in reducing the risk of persistent MRSA colonization among known carriers.

Risk assessment and laboratory investigation of respiratory illness in travellers returning to Singapore 2012-2015: experience from the MERS-CoV Surveillance Programme.

Since the emergence of Middle East respiratory syndrome coronavirus (MERS-CoV), Singapore has enhanced its national surveillance system to detect the potential importation of this novel pathogen. Using the guidelines from the Singapore Ministry of Health, a suspect case was defined as a person with clinical signs and symptoms suggestive of pneumonia or severe respiratory infection with breathlessness, and with an epidemiological link to countries where MERS-CoV cases had been reported within the preceding 14 days. This report describes a retrospective review of 851 suspected MERS-CoV cases assessed at the adult tertiary-care hospital in Singapore between September 2012 and December 2015. In total, 262 patients (31%) were hospitalized. All had MERS-CoV infection ruled out by RT-PCR or clinical assessment. Two hundred and thirty (88%) of the hospitalized patients were also investigated for influenza virus by RT-PCR. Of these, 62 (27%) tested positive for seasonal influenza. None of the patients with positive influenza results had been vaccinated in the year prior to hospital admission. Ninety-three (36%) out of the 262 hospitalized patients had clinical and/or radiological evidence of pneumonia. This study demonstrates the potential benefits of pre-travel vaccination against influenza and pneumococcal disease.

Vancomycin-resistant enterococci with reduced daptomycin susceptibility in Singapore: prevalence and associated factors.

Prevalence of vancomycin-resistant enterococci (VRE) and use of daptomycin are increasing in Asia. To determine the prevalence of daptomycin non-susceptible enterococci (DNSE) and understand factors associated with reduced daptomycin susceptibility in VRE, we conducted a case-control study in a 1600-bed adult tertiary hospital in Singapore. All VRE isolates from inpatients in 2012 were tested for daptomycin susceptibility. Patients with VRE isolates of daptomycin minimum inhibitory concentration (MIC) ⩾3 µg/ml were classified as daptomycin-reduced susceptible VRE (DRS-VRE) and those with daptomycin MIC 4 µg/ml (DNSE). About half (135, 55%) had reduced susceptibility to daptomycin (MIC 3-4 µg/ml). None in the DS-VRE group had prior exposure to daptomycin. After adjusting for age, gender, comorbidity, hospitalization duration, surgical history, indwelling device use, and duration of antibiotic exposure in the prior 3 months, >1 movement between wards [odds ratio (OR) 0·35, 95% confidence interval (CI) 0·16-0·74, P = 0·006] and minocycline resistance (OR 0·45, 95% CI 0·25-0·84, P = 0·011) were independently associated with DRS-VRE. Our study suggests that daptomycin exposure, >1 movement between wards, and resistance to minocycline, were associated with reduced daptomycin susceptibility in VRE.

Length of stay an important mediator of hospital-acquired methicillin-resistant Staphylococcus aureus.

Hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) is becoming increasingly established in Asian hospitals. The primary aim of this study was to decompose the risk factors for HA-MRSA based on conceptual clinical pathways. The secondary aim was to show the amount of effect attributable to antibiotic exposure and total length of stay before outcome (LBO) so that institutions can manage at-risk patients accordingly. A case-control study consisting of 1200 inpatients was conducted in a large tertiary hospital in Singapore between January and December 2006. Results from the generalized structural equation model (GSEM) show that LBO [adjusted odds ratio (aOR) 14·9, 95% confidence interval (CI) 8·7-25·5], prior hospitalization (aOR 6·2, 95% CI 3·3-11·5), and cumulative antibiotic exposure (aOR 3·5, 95% CI 2·3-5·3), directly affected HA-MRSA acquisition. LBO accounted for the majority of the effects due to age (100%), immunosuppression (67%), and surgery (96%), and to a lesser extent for male gender (22%). Our model enabled us to account and quantify effects of intermediaries. LBO was found to be an important mediator of age, immunosuppression and surgery on MRSA infection. Traditional regression approaches will not only give different conclusions but also underestimate the effects. Hospitals should minimize the hospital stay when possible to reduce the risk of MRSA.

Chikungunya fever in Singapore: acute clinical and laboratory features, and factors associated with persistent arthralgia.

BACKGROUND: In Singapore, the first local outbreak of chikungunya was reported in January 2008, followed by a larger outbreak occurred in August 2008. During the initial outbreak period, a strict containment strategy was adopted and all chikungunya PCR-confirmed cases were isolated and hospitalised at the designated national outbreak management centre. OBJECTIVES: To detail daily clinical and laboratory features of chikungunya cases during acute illness, and determine factors associated with persistent arthralgia at week 6. STUDY DESIGN: Prospective cohort study of patients with PCR-confirmed chikungunya infection and hospitalised within 5 days of illness onset, from 1st August to 10th November 2008. Post-hospital discharge, patients were followed up at the specialist outpatient clinic, and assessed for arthralgia at week 6 of illness. RESULTS: Of the 97 patients in the study, the most common presenting symptoms were fever (89.7%) and arthralgia (87.6%). Mean nadir leukocyte and platelet counts were 3.5(SD 1.9) × 10(9)/L and 165(SD 42) × 10(9)/L respectively. Of the 39 patients who were evaluated at week 6, 14 (35.9%) had persistent arthralgia. Those with persistent arthralgia tended to be females (p = 0.003), and had a lower peak creatinine level (p = 0.036) than those without. Peak viral load (p = 0.664), and duration of fever (p = 0.056) and viremia (p = 0.55) respectively, were not significantly different between those with persistent arthralgia and those without. CONCLUSIONS: This study details the daily clinical and laboratory features of chikungunya patients during acute illness. Those with persistent arthralgia tended to be females, who had significantly lower peak creatinine level.

Clinical features and epidemiology of chikungunya infection in Singapore.

Chikungunya is a re-emerging mosquito-borne viral infection that has spread from East Africa to Indian Ocean islands and re-emerged in India since 2004. In Malaysia, chikungunya re-emerged after a hiatus of seven years, causing a localised outbreak in a north-western coastal town in 2006 and subsequently widespread outbreaks in 2008. Since the first local outbreak of chikungunya in Singapore in January 2008, chikungunya infections have been increasingly reported in Singapore. In this case series, five patients aged 37-62 years, with chikungunya infection confirmed in August 2008, were reported. Three of the five were male, and only one had medical comorbidities. Two had a travel history to Johor, Malaysia, where local outbreaks of chikungunya had been reported. Fever, arthralgia and rash were the most common symptoms. Fever lasted four to five days while viraemia lasted four to 11 days, persisting two to three days after defervescence in three patients. A biphasic pattern of fever was observed in two patients. Leucopenia was noted in all patients, while mild thrombocytopenia and transaminitis occurred in three of five patients. Two patients had persistent polyarthralgia at two to three weeks after the onset of symptoms. Fever, arthralgia and rash should prompt consideration of acute chikungunya in Singapore. While taking the travel history, doctors should be mindful that indigenous chikungunya cases can occur.