Effect of Temperature and Tissue Type on the Development of Myiasis Causing Fly; Chrysomya bezziana (Diptera: Calliphoridae).

Chrysomya bezziana Villeneuve is the major human myiasis producer in tropical countries, including Sri Lanka. Although of great medical and veterinary importance, only a single study has been published on the development of C. bezziana. This limitation is due in part to the difficulty of maintaining this species in a colony outside of using a living host. In this study, a novel technique that overcomes this limitation is presented along with development data for C. bezziana fed on three different meat types: swine muscle, swine liver, and bovine muscle at two temperature regimes: 35 and 37°C. The optimum development of C. bezziana was recorded at 35°C in bovine muscle (262.20 h) followed by swine muscle (286.00 h) and swine liver (307.00 h). Data from the current study indicate tissue type significantly impacts change in length and width of larvae over time, whereas the two temperatures examined had no significant effect.

A low cost rapid urease test to detect Helicobacter pylori infection in resource limited settings.

The aim of the study was to evaluate the suitability of a modified one minute rapid urease test (one day rapid urease test) as a low cost H. pylori detection method. A sample of 205 patients clinically suspected of having H. pylori infection was tested. One day rapid urease test and histology based H. pylori tests (the gold standard) were performed on endoscopic antral biopsies. There were 6 true positives, 191 true negatives, 8 false positives and zero false negatives. The sensitivity, specificity and positive (PPV) and negative predictive values (NPV) of the test were 100%, 96%, 42.9%, and 100% respectively. The cost per patient was 0.3US$. High sensitivity, specificity and NPV, low cost and simplicity of method were the advantages of the test and the main limitation was low PPV. Hence, one day rapid urease test can be considered as a suitable low cost method to detect H. pylori infection in resource limited settings.

Prevalence of Helicobacter pylori in benign gastric ulcers in a cohort of Sri Lankan patients.

Helicobacter pylori prevalence is decreasing globally and prevalence of non H. pylori gastric ulcers is increasing. The following study was conducted to assess the prevalence of H. pylori in benign gastric ulcers in a sample of Sri Lankan patients. This was a cross-sectional study of 59 dyspeptic patients with benign gastric ulcers. Multiple endoscopic gastric biopsies were obtained and histology, immunohistochemistry and polymerase chain reaction were performed for H. pylori detection. An immunochromatography assay was performed to detect blood anti H. pylori antibodies. Four (6.8%) were positive for H. pylori. Therefore, it is likely that most benign gastric ulcers are of non-H. pylori aetiology.