Predicting outbreaks: a spatial risk assessment of West Nile virus in British Columbia

Background  

West Nile virus (WNv) has recently emerged as a health threat to the North American population. After the initial disease outbreak in New York City in 1999, WNv has spread widely and quickly across North America to every contiguous American state and Canadian province, with the exceptions of British Columbia (BC), Prince Edward Island and Newfoundland. In this study we develop models of mosquito population dynamics for Culex tarsalis and C. pipiens, and create a spatial risk assessment of WNv prior to its arrival in BC by creating a raster-based mosquito abundance model using basic geographic and temperature data. Among the parameters included in the model are spatial factors determined from the locations of BC Centre for Disease Control mosquito traps (e.g., distance of the trap from the closest wetland or lake), while other parameters were obtained from the literature. Factors not considered in the current assessment but which could influence the results are also discussed.     

Comparison between two valsalva techniques for improvement of hypopharyngeal nasendoscopy: a preliminary communication

Objective: To compare the nasal valsalva with the trumpet manoeuvre and anterior neck skin traction as aids to nasendoscopic examination of the hypopharynx. Design: Randomised, controlled comparison of examination techniques. Setting: Single tertiary referral centre. Participants: Twenty‐six adult patients requiring hypopharyngeal nasendoscopic examination were recruited. Patients were examined with both techniques in a randomised order that was recorded to video cassette. Main Outcome Measures: Blinded assessment of the percentage visualisation of the pyriform fossae, post‐cricoid and upper oesophageal sphincter was carried out by three consultant otolaryngologists independently. Results: Mean percentage scores (and 95% confidence intervals) for nasal valsalva versus trumpet manoeuvre for the three consultants, respectively, were as follows: right pyriform fossa: 77(68, 87) versus 80(71, 91), 61(55, 66) versus 60(54, 66), 46(38, 54) versus 45(37, 54); left pyriform fossa: 76(65, 87) versus 80(69, 91), 59(53, 64) versus 55(49, 61), 42(35, 49) versus 42(35, 50); post‐cricoid: 55(44, 67) versus 59(47, 71), 53(46, 60) versus 53(46, 60), 32(25, 39) versus 32(25, 39); upper oesophageal sphincter: 11(1, 21) versus 21(11, 31), 15(9, 21) versus 20(14, 26), 4(0, 8) versus 7(3, 11). No significant difference was found between the two techniques at any subsite. Individual differences were noted in a minority of patients where one or other technique gave a clearly improved view. Conclusions: The nasal valsalva and the trumpet manoeuvre with anterior neck skin traction are complementary techniques for improving the view of the hypopharynx.     

A randomized trial of ceftriaxone versus trimethoprim-sulfamethoxazole to prevent ventriculoperitoneal shunt infection.

BACKGROUND AND PURPOSE: Shunt infection represents a particularly morbid condition, which can also result in mortality. In order to decrease the high morbidity and mortality rates, prevention is an essential step. The purpose of this study was to compare the prophylactic use of ceftriaxone and trimethoprim-sulfamethoxazole (SXT) for the prevention of ventriculoperitoneal (VP) shunt infection. METHODS: In this prospective, single-institution, randomized clinical trial, 107 children with hydrocephalus and an indication for shunting were randomly assigned to prophylaxis with ceftriaxone (n = 50) or SXT (55), each administered as a single dose during anesthesia and two divided doses postoperatively. Patients were followed up for at least one year. RESULTS: The mean age of patients was 15 months, and 85% were aged 6 months or younger. During the first postoperative year, meningitis occurred in 13.5% of patients receiving ceftriaxone and 14.5% of the SXT group, with no statistically significant difference between the groups. Younger age, presence of cerebrospinal fluid leakage and aqueductal stenosis as a cause of hydrocephalus showed significant correlation with meningitis occurrence on univariate analysis. However, only the latter 2 factors were associated with meningitis on multivariate analysis. The risk of shunt infection did not correlate with the gender of the patient, time of VP shunt surgery, or duration of hospitalization for shunting. CONCLUSION: Ceftriaxone and SXT showed similar efficacy in preventing shunt infection. Cerebrospinal fluid leakage before or after VP shunt placement and aqueductal stenosis were independent risk factors for meningitis after VP shunt.     

Breast feeding may protect children against Campylobacter jejuni associated diarrhoea

To investigate the bacterial etiology of infant diarrhea in Karachi, Pakistan, 180 rectal swab samples collected from diarrhea patients under 5 years of age and 30 samples from age- and sex-matched healthy children were analyzed. Enteropathogenic organisms were isolated from 70 case samples (38.9%). The two most common etiologic agents were Campylobacter jejuni (19.4%) and Aeromonas hydrophilia (6.1%). Salmonella, Shigella, and Yersina appear to have a limited incidence in this age group. None of the control specimens yielded any enteropathogen. Breast-fed infants had a significantly lower risk of enteric infection. A pathogen was isolated in 26.0% of samples from breast-fed children with diarrhea compared with 46.8% of samples from bottle-fed diarrhea patients. All C jejuni infections identified in this study involved bottle-fed children. Boiled water was used to prepare infant formula in only 31.1% of these patients. These findings are consistent with those of other studies showing a decreased rate or severity of diarrhea in breast-fed infants. Mothers should be encouraged to breast feed their infants or, if this is not possible, to use boiled water for the preparation of infant formula.     

Glycaemic responses to cereal-based Indian food preparations in patients with non-insulin-dependent diabetes mellitus and normal subjects

The in vivo glycaemic responses to six cereal-based foods traditionally consumed in South India were evaluated in patients with non-insulin-dependent diabetes mellitus (NIDDM) and healthy volunteers. All foods contained 50 g carbohydrate and were compared with a 50 g glucose load. Also studied were the in vitro starch digestibility and nutrient composition of the foods. The postprandial responses to the foods at 30, 60 and 120 min were significantly (P < 0.05) lower than those to the reference glucose, in both groups. The peak glucose responses for three foods, i.e. chapatti, idli and poori, occurred 60 min postprandially in both groups. The glycaemic index (GI) values ranged from 67 to 90 in NIDDM and from 44 to 69 in healthy subjects with no significant differences within the groups. Significant relationships were observed between peak responses and area under the curve for foods in patients with NIDDM and in vitro rate of starch hydrolysis (r 0.83, r 0.85, P < 0.05). The GI values predicted using in vitro data were found to be similar to the GI values observed in patients with NIDDM. The GI concept is useful for identifying foods in the habitual Indian diet with attributes of the desired glycaemic effect such as delayed peak rise and low area under the curve.     

Chronic inflammatory demyelinating polyradiculoneuropathy: A role for haematopoietic stem cell transplantation?

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a clinical syndrome of a chronic progressive or relapsing and remitting, symmetrical, sensory and motor radiculoneuropathy. The immune reaction in CIDP is characterised by selective inflammation of peripheral nerves and is probably due to the interaction of cellular and humoral responses. Only three treatments for CIDP have demonstrated benefit in randomised studies, corticosteroids, plasma exchange and intravenous immunoglobulin. 25% of patients fail to respond or do not respond adequately to these treatments. Experimental data in animal models have shown that several autoimmune disorders, either congenital or acquired, can be transferred and/or treated by the transplantation of bone marrow stem cells. Haematopoietic stem cell transplantation (HSCT) has been performed with varying success in over 700 patients with autoimmune disorders throughout Europe. The experience in CIDP is very limited. This article will review current understanding of CIDP and experience of the use of HSCT in refractory CIDP.