A cocoon immunisation strategy against pertussis for infants: does it make sense for Ontario?

Pertussis deaths occur primarily among infants who have not been fully immunised. In Ontario, Canada, an adult booster dose was recently added to the publicly funded immunisation programme. We applied number-needed-to-treat analyses to estimate the number of adults that would need to be vaccinated (NNV) to prevent pertussis disease, hospitalisation and death among infants if a cocoon strategy were implemented. NNV=1/(P(M) X R) + 1/(P(F) X R), where P(M),P(F) (proportion of infants infected by mothers, fathers) were sourced from several studies. Rates of disease, hospitalisation or death (R) were derived from Ontario's reportable disease data and Discharge Abstract Database. After adjusting for under-reporting, the NNV to prevent one case, hospitalisation or death from pertussis was between 500-6,400, 12,000-63,000 and 1.1-12.8 million, respectively. Without adjustment, NNV increased to 5,000-60,000, 55,000-297,000 and 2.5-30.2 million, respectively. Rarer outcomes were associated with higher NNV. These analyses demonstrate the relative inefficiency of a cocoon strategy in Ontario, which has a well-established universal immunisation programme with relatively high coverage and low disease incidence. Other jurisdictions considering a cocoon programme should consider their local epidemiology.

Prolonged Pertussis Outbreak in Ontario Originating in an Under-immunized Religious Community.

Abstract. BACKGROUND: A prolonged pertussis outbreak began in Ontario in November 2011 in an under-immunized religious community and subsequently spread to the general population and a second religious community in the same region of the province. OBJECTIVE: To compare the epidemiology in the religious communities to that of the general population within the affected jurisdictions. METHODS: The analysis includes cases reported through the integrated Public Health Information System (iPHIS) between November 1, 2011 and April 15, 2013 that met the outbreak case definition. Health unit staff assessed whether cases were members of religious communities through case investigations and collected information on immunization status, treatment and outcomes. RESULTS: A total of 443 confirmed and probable outbreak cases were reported in 7 health units. The outbreak began in one religious community (138 cases), before spreading to the general population in the region (273 cases). A second under-immunized community within the region experienced 32 cases. Thirteen cases were hospitalized and no deaths were reported. Disease peaked earlier in the religious community; cases were significantly younger, more likely to be at high risk for pertussis and more likely to be unimmunized. Among the fully immunized general population, 51% of cases were between 10-14 years and with a median of 5.6 years since their last immunization. CONCLUSION: The epidemiology of pertussis in the under-immunized community is distinct from the general population. Transmission of pertussis to the general community is not unexpected during an outbreak; however, the proportion of cases up to date with immunization warrants further investigation.

Documenting the elimination of measles, rubella and congenital rubella syndrome in Ontario: 2009-12.

BACKGROUND: Under the guidance of the Pan American Health Organization (PAHO), countries of the Americas are currently documenting the elimination of measles, rubella, and congenital rubella syndrome. OBJECTIVE: This paper describes Ontario's progress in documenting the elimination of these conditions between 2009 and 2012. METHODS: All possible case classifications, including those that did not meet surveillance case definitions, were extracted from the provincial reportable disease database, the integrated Public Health Information System (iPHIS). Data were analyzed against select criteria specified by the PAHO, specifically with respect to epidemiology, vaccination coverage, and the quality of the surveillance system. RESULTS: There were no known endemic cases of measles, rubella or congenital rubella syndrome reported in Ontario during the study period. Cases were predominantly the result of importation, as these diseases remain endemic in many countries. A total of 27 confirmed cases of measles were reported over the four-year period, most of which could be verified as being directly or indirectly linked with travel outside Canada. In addition, five confirmed cases of rubella and one case of imported congenital rubella syndrome were identified. A review of immunization coverage and surveillance data quality identified gaps. The combined annual rates of suspected measles and rubella cases (between 0.7 and 1.1 cases per 100,000 population) and suspected congenital rubella syndrome cases (0.21 to 0.49 cases per 10,000 live births) were below PAHO's thresholds. Also, the frequent absence of immunization and travel histories within iPHIS was of concern (77.3% and 44.6% respectively). CONCLUSION: These results support Ontario's sustained elimination status. However, in order to satisfactorily meet PAHO's requirements for documenting the elimination of these diseases, continued vigilance is required. Efforts are currently under way within Ontario to improve reporting.

Singapore cancer trends in the last decade.

In this review, we examine the trends in cancer incidence, mortality and survival in the last decade, using published data from the Singapore Cancer Registry in the period 1998 to 2009. While overall cancer incidences have remained stable, overall cancer mortality rates have declined for both genders. Thus, it is not surprising that there was an improvement in cancer survival. A steady decrease in lung cancer among males and females was observed, thereby leading to a drop in its cancer ranking. In the last five years, the most frequently occurring cancer was colorectal cancer among the male population and breast cancer among females. Survival for both cancers remained relatively optimistic. There is good reason to pay special attention to colorectal cancer due to its high frequency of occurrence among the Singapore population and because it is amenable to early detection via screening.

Mammographic density and its interaction with other breast cancer risk factors in an Asian population.

BACKGROUND: Joint effects of mammographic density and other risk factors on breast cancer risk remain unclear. METHODS: From The Singapore Breast Screening Project, we selected 491 cases and 982 controls. Mammographic density was measured quantitatively. Data analysis was by conditional logistic regression. RESULTS: Density was a significant risk factor, adjusting for other factors. Density of 76-100% had an odds ratio of 5.54 (95% CI 2.38-12.90) compared with 0-10%. Density had significant interactions with body mass index and oral contraceptive use (P=0.02). CONCLUSIONS: Percent density increases breast cancer risk in addition to effects of other risk factors, and modifies the effects of BMI and OCs.

Effect of childbirth after treatment on long-term survival from breast cancer.

BACKGROUND: This study quantified long-term absolute and relative mortality risks of survivors of breast cancer with subsequent childbirth. METHODS: The Singapore Birth Register (n = 319,437), Swedish Multi-Generation Register (n = 11 million) and population-based cancer registries were linked to identify 492 women with childbirth after breast cancer. For these women, cumulative mortality risks and standardized mortality ratios (SMRs) were calculated and compared with those of 8529 women aged less than 40 years with breast cancer without subsequent childbirth, and with those predicted by Adjuvant! Online. RESULTS: Women with subsequent childbirth had a lower 15-year cumulative overall mortality rate than other women with breast cancer (16.8 (95 per cent confidence interval (c.i.) 13.3 to 20.9) versus 40.7 (39.5 to 41.9) per cent), but a higher relative mortality risk than the background population (SMR 13.6, 95 per cent c.i. 10.6 to 17.3). Mortality risks decreased significantly with increasing interval between diagnosis and subsequent childbirth. Mean 10-year cumulative mortality risks of women with subsequent childbirth were within the range of 10-year mortality predicted by Adjuvant! Online for women with T1 N0 tumours in otherwise perfect health. CONCLUSION: This study reinforced the view that pregnancy after breast cancer is not detrimental to survival. However, women who gave birth after this diagnosis had substantially higher mortality risks than young women in the general population. This information may be a valuable addition to routine mortality estimates.

Clinical predictors of abnormal computed tomography findings in patients with altered mental status.

INTRODUCTION: While non-contrast computed tomography (CT) of the brain can be used to rapidly identify patients with altered mental status (AMS) in the emergency department (ED), with an acute intracranial bleed or infarct, a wide variation in its use exists. The aim of this pilot study was to identify the clinical predictors of an abnormal CT result in ED patients with AMS. METHODS: We conducted a retrospective study of patients aged 15 years and older presenting with undifferentiated AMS in a busy urban ED over one year. Data collected included demographical, clinical, laboratory and radiological features. The primary outcome of interest was the presence of an abnormal CT result defined as an acute infarct or intracranial bleed. Secondary outcomes were clinical predictors of an abnormal CT result. The data was analysed using descriptive statistics. Logistic regression was used to identify clinical predictors of an abnormal CT result. Odds ratios (ORs) were reported with 95 percent confidence intervals (CIs). RESULTS: 578 patients were recruited, of which 284 (49.1 percent) were males. 327 (56.6 percent) patients underwent CT of the brain. 128 scans (39.1 percent) were abnormal. Logistic regression revealed seven clinical features that were associated with an abnormal CT result. They were mean age greater than or equal to 73 years (OR 1.03; 95 percent CI 1.015-1.045), drowsiness or unresponsiveness (OR 1.73; 95 percent CI 0.17-17.72), previous cerebrovascular accident (OR 2.03; 95 percent CI 0.82-5.02), previous epilepsy (OR 1.63; 95 percent CI 0.63-4.19), tachycardia [greater than 120/min] (OR 1.16; 95 percent CI 0.38-3.54), bradycardia [less than 60/min] (OR 1.35; 95 percent CI 0.19-9.59) and exposure to drugs (OR 1.90; 95 percent CI 0.58-6.26). CONCLUSION: We identified seven clinical predictors of an abnormal CT result in AMS patients. Future research in prospective studies is needed to validate these findings.

24-Hour observational ward management of diabetic patients presenting with hypoglycaemia: a prospective observational study.

BACKGROUND: A 24 h observational ward was set up in the study hospital emergency department (ED) in September 2005 to manage a group of patients with specific conditions including hypoglycaemia that require only short focused inpatient care. AIM: To evaluate the efficacy and safety of the management of hypoglycaemia in the observational ward via criteria of successful discharge of patients from the observational ward within 24 h and the recurrence of hypoglycaemia after discharge. METHODS: Hypoglycaemic patients admitted to the observational ward had their treatment and evaluation performed within 24 h. A protocol based on current available literature was formulated. Data were collected prospectively and included patient demographics, the duration and type of diabetes mellitus, current medications and treatment given. Patients were discharged only after a set of strict discharge criteria was fulfilled, and were followed up by telephone interviews at 7 and 28 days after discharge. RESULTS: A total of 203 patients were recruited. Of these, 170 (83.7%) patients were discharged and 33 (16.3%) were transferred to an inpatient team for a longer period of treatment. The median length of stay in the observational ward was 23.0 h. Of the 170 patients discharged, 151 (88.8%) were contacted at 7 and 28 days after discharge. Six patients had symptoms of recurrent hypoglycaemia, two of whom reattended the ED and had to be admitted. The remaining four patients had mild symptoms that were self-managed at home. Two other patients reattended for conditions not related to hypoglycaemia. Nineteen patients could not be contacted, but there was no record of any reattendances at the ED among this group of patients. CONCLUSION: There are currently no recommendations regarding the length of stay in hospital for patients with severe hypoglycaemia. This study shows that selected patients can be treated effectively and safely in a 24 hour observational ward.

Patient satisfaction in an observation unit: the Consumer Assessment of Health Providers and Systems Hospital Survey.

BACKGROUND: The growing demand for inpatient beds in Singapore has led Tan Tock Seng Hospital to set up an observation medicine unit where patients are monitored and discharged within a 24-h period. METHODS: Using the Consumer Assessment of Health Providers and Systems (CAHPS) Hospital Survey, this descriptive study examines the satisfaction levels of patients admitted into an observation unit, in particular the communication between patients and doctors and nurses. The anonymous surveys were either self-administered by the patients or by the research assistant or nurses. RESULTS: 271 patients completed the survey, with 96% of patients satisfied with the politeness (ie, treating them with courtesy and respect, listening carefully to them) of the medical staff. More highly educated patients were more satisfied with the communication between the doctors or nurses, compared with less educated patients (p<0.05). However, less educated patients gave a higher rating of their observation unit stay than more educated patients (p<0.05). CONCLUSION: With patient satisfaction becoming increasingly important as an indicator of the quality of care in the present healthcare environment, doctors and nurses should seek to improve their communication with their patients so as to ensure that patients are satisfied and receive quality care.

Penile strangulation: report of two unusual cases.

We report two cases of penile strangulation that presented to our emergency department. In the first case, a 60-year-old man, the object of strangulation was a metallic ring that was extricated using an orthopaedic cutter in the operating theatre. The patient recovered uneventfully. In the second case, a 77-year-old man, the object of strangulation was a plastic bottle, which was extricated using surgical instruments in the emergency department, but the patient subsequently developed postobstructive diuresis. The first case illustrates the difficulty that may be encountered in this delicate yet urgent situation, while the second case reports a rare complication.

Acute ophthalmoplegia (without ataxia) associated with anti-GQ1b antibody.

BACKGROUND: Anti-GQ1b antibody has been found in Miller Fisher syndrome (MFS), Guillain-Barré syndrome (GBS) with ophthalmoplegia, Bickerstaff brainstem encephalitis (BBE), and acute ophthalmoplegia without ataxia (AO). The aim of this study was to determine the clinical features of AO associated with anti-GQ1b antibody. METHODS: We retrospectively collected 34 patients with anti-GQ1b antibody syndrome. Of these patients, 31 patients had ophthalmoplegia. The patients with ophthalmoplegia were classified into MFS (n = 13), AO (n = 11), GBS with ophthalmoplegia (n = 6), and BBE (n = 1). We analyzed clinical features and patterns of external and internal ophthalmoplegia of AO, and neuro-ophthalmologic findings were compared with those of other anti-GQ1b syndromes with ophthalmoplegia. RESULTS: AO was observed in 11 (32.4%) of the 34 patients with anti-GQ1b antibody. External ophthalmoparesis was present in all the patients and included mixed horizontal-vertical (n = 7), pure horizontal (n = 3), and pure vertical gaze palsy (n = 1). Binocular involvement was common, but unilateral ophthalmoparesis was also observed in 27.3%. Other findings included ptosis (n = 5, 45.5%) and internal ophthalmoplegia (n = 6, 54.5%). Other anti-GQ1b antibody syndromes had prominent neurologic signs including ataxia, weakness, and facial palsy in addition to ophthalmoplegia. The patterns of neuro-ophthalmologic findings did not differ between AO and other anti-GQ1b antibody syndromes with ophthalmoplegia. CONCLUSIONS: Acute ophthalmoplegia (AO) commonly occurs in anti-GQ1b antibody syndrome and manifests as various combinations of external and internal ophthalmoplegia. Internal ophthalmoplegia is fairly common and unilateral involvement may occur in AO.

Diagnostic laparoscopy in the evaluation of right lower abdominal pain: a one-year audit.

INTRODUCTION: Acute appendicitis is the commonest cause for right lower abdominal pain. Clinical features, laboratory and imaging investigations are either not very sensitive or specific, and neither is therapeutic. We aimed to define the role of diagnostic laparoscopy in patients with right lower abdominal pain. METHODS: Data was collected retrospectively from January 1, 2005 to December 31, 2005. Patients admitted to the Emergency Department and subsequently transferred to the Department of Surgery, National University Hospital, Singapore, with right lower abdominal pain and who eventually underwent diagnostic laparoscopy were evaluated. RESULTS: 691 patients with right lower abdominal pain were admitted with suspected diagnosis of appendicitis. Diagnostic laparoscopy was undertaken in 103 patients aged 17-71 years old. Of the 83 females, 78 (94 percent) were premenopausal . Histology-proven acute appendicitis was diagnosed in 78 (75.7 percent) patients. Interestingly, within this group, 25.6 percent had other concomitant pathologies found on laparoscopy. 25 patients had a normal appendix; gynaecological causes accounted for pain in 15 of these 25 (60 percent) cases. In four (3.9 percent) patients, no pathology was found. Complication rate was 1.9 percent, which included ileus in two patients. In 32 (31.1 percent) patients, diagnostic laparoscopy altered the management plan, requiring either intervention or care by a subspecialty. CONCLUSION: Diagnostic laparoscopy is useful in evaluating patients with right lower abdominal pain, especially in those with equivocal signs of acute appendicitis. It also has the additional benefit of being therapeutic. Premenopausal women benefit the most from this procedure.

Adherence and efficacy of an external teat sealant to prevent new intramammary infections in the dry period.

The efficacy and adherence of an external teat sealant applied at drying off was evaluated in 2 studies between 1997 and 1999. At drying off, 2 quarters were randomized to receive intramammary dry-cow antibiotic therapy, and the remaining 2 quarters were treated with either a single or double application of external teat sealant. Approximately 3 d before calving, all teats that had been dipped at drying off were redipped in a single coating of teat sealant. Adherence of the teat sealant was scored for the first 2 wk after drying off, and physical traits of the teat skin and teat ends were recorded. Quarter milk samples were collected 1 wk before drying off, at drying off, 0 to 7 d, and 14 to 21 d postcalving. Somatic cell counts were determined from quarter samples taken at d 7 and 14 to 21 d after calving. Data were analyzed from 172 dry periods of 162 cows. The mean time of sealant adherence following drying off application was 3 +/- 0.13 d. Double sealant application significantly increased the duration of adherence by 0.67 d. Teats that had teat sealant applied twice at drying off and that had up to 3 d of adherence had the lowest linear score (LS) at 14 to 21 d (1.89 +/- 0.31) of all quarters. The LS of quarters that received antibiotic therapy only was 2.27 +/- 0.19. The majority of intramammary infections identified at drying off were caused by the minor pathogens, coagulase-negative staphylococci and Corynebacterium bovis (51 and 23%, respectively). The results from this study indicate that duration of sealant adherence to the teat-end should be considered when evaluating the impact of teat sealant treatment at drying off on the level of infection after calving. Double sealant application, cooler seasons, and longer teat lengths were associated with a significant increase in the duration of sealant adherence to the teat-end.

Herd management factors that affect duration and variation of adherence of an external teat sealant.

During 1998 and 1999, a purposive sample of Ontario dairy herds was enrolled in a study to examine management factors associated with adherence of an external teat sealant. A total of 74 herds were recruited that had previously complied with a provincial Sentinel Herd mastitis study. All herds were sent a management survey and a commercially available external teat sealant product. The sealant was applied to all cows in first lactation or greater that were scheduled to go dry. Adherence of the teat sealant was scored on a scale of 1 to 5 (1 = sealant completely removed) for the first 12 d following dry off. Complete data were analyzed from 806 cows in 48 herds (mean of 17 cows/herd). Mean duration of adherence of the teat sealant was 4 d (range 1 to 7 d). Of the management factors recorded, only changing the feed to reduce milk production prior to drying off was significantly associated with 0.78-d prolonged adherence. No factors related to dry cow housing, bedding material, or floor surface were associated with the duration of adherence. The variance around the duration of adherence was examined. The median variance of adherence was 3.0 d(2), which was equivalent to a standard deviation of 2.6 d. Herds in which dry cows were housed in tie-stall barns, and the herds that used a penicillin and novobiocin combination dry cow antibiotic had the greatest variation. We concluded that modifying the ration to reduce milk production enhanced adherence of an external teat sealant. Teat-end preparation prior to application of the teat sealant is an important factor to consider when choosing to adopt this dry period mastitis prevention strategy. This study demonstrates that beyond cow- and quarter-level factors, herd management factors can influence the duration and variation of sealant adherence experienced among different herds.

A systemic iridoviral disease in mullet, Mugil cephalus L., and tiger grouper, Epinephelus fuscoguttatus Forsskal: a first report and study.

A systemic iridoviral disease associated with high mortality was initially recognized in cultured mullet, Mugil cephalus L., and tiger grouper, Epinephelus fuscoguttatus Forsskal, by histopathology and transmission electron microscopy. Polymerase chain reaction was performed on tissues and viral isolates, using four published primer sets developed for the Red Sea bream iridovirus (RSIV). An indirect fluorescent antibody test was also performed on virus-infected ATCC gruntfin (GF) and seabass, Lates calcarifer Bloch, (SB) cells using a monoclonal antibody, RSIV M10. Our results suggested that the mullet and tiger grouper iridovirus bears genetic and antigenic similarities to RSIV.

The pathology of systemic iridoviral disease in fish.

Iridoviruses have been associated with severe disease and economic loss in farmed food fish and ornamental fish, with mortality often reported to reach 50% or more. In the present study, three tropical marine food fish species and four tropical freshwater ornamental fish species with systemic iridovirus infections were examined histopathologically and ultrastructurally. Light microscopy consistently revealed pale to intensely basophilic hypertrophied virus-infected cells in spleen, kidney and intestine from all seven species. Ultrastructural examination showed changes in the vascular endothelium overlying hypertrophied virus-infected cells suggestive of pressure necrosis. Viral isolation was improved by the use of fibroblastic cell lines. This, together with the sub-endothelial location of infected cells in all infected species examined, suggests that systemic iridoviruses are mesotheliotropic.

Characterization of a novel ranavirus isolated from grouper Epinephelus tauvina.

A large icosahedral virus was isolated from diseased grouper Epinephelus tauvina. The virus grew well in several cultured fish cell lines, with stable and high infectivity after serial passages in grouper cell line (GP). The virus was sensitive to both acid and heat treatments. Virus replication was inhibited by 5-iodo-2-deoxyuridine (IUDR), indicative of a DNA-containing genome. The virus infectivity was reduced with ether treatment, suggesting that the virus was lipid-enveloped. Electron micrographs showed abundant cytoplasmic icosahedral virons in the virus-infected GP cells. The size of the intracellular nucleocapsid was 154 nm between the opposite sides, or 176 nm between the opposite vertices with an inner electron-dense core of 93 nm. Virus particles were released through budding from plasma membranes with a size of 200 nm in diameter. SDS-PAGE of purified virus revealed 20 structural protein bands and a major capsid protein (MCP) of 49 kDa. A DNA fragment of approximately 500 nucleotides was successfully amplified by polymerase chain reaction (PCR) using the primers from conserved regions of the MCP gene of frog virus 3 (FV3), the type species of Ranavirus. Subsequent multiple alignment and phylogenetic analysis showed that the newly isolated grouper virus was closely related to largemouth bass virus (LMBV), FV3 and Regina ranavirus (RRV). Our data suggests that the virus isolate is a novel member of genus Ranavirus, family Iridoviridae. We tentatively name the virus as Singapore grouper iridovirus (SGIV). SGIV was able to cause serious systemic disease capable of killing 96% of grouper fry.

Sensitivity and specificity of somatic cell count and California Mastitis Test for identifying intramammary infection in early lactation.

Associations between values for the somatic cell count (SCC) or the California Mastitis Test (CMT) and intramammary infection (IMI) were studied in 131 dairy cows from three herds during the first 10 d post-calving. Intramammary infection was defined as the presence of one or two bacterial species in one or both quarter milk samples taken within 12 h of calving and at d 3 postcalving. Quarter milk samples identified IMI in 36% of glands. Values for SCC declined at a significantly faster rate over the first 10 d postcalving in non-infected quarters than in infected quarters. The usefulness of quarter milk SCC and CMT for screening was evaluated by calculating the sensitivity and specificity for various threshold values and days postcalving. A SCC threshold of 100,000 cells/ml for quarter samples evaluated on d 5 postcalving had the maximal sensitivity and specificity for detecting IMI. Evaluation of the CMT samples taken on d 3 postcalving using a threshold reaction of greater than zero had the highest sensitivity and specificity for detecting IMI. With this CMT sampling scheme, the sensitivities for detecting IMI with any pathogen, IMI with a major pathogen, and IMI with a minor pathogen were 56.7, 66.7, and 49.5, respectively. The CMT could have a useful role in dairy herd monitoring programs as a screening test to detect fresh cows with IMI caused by major pathogens.