The incidence of malaria in travellers to South-East Asia: is local malaria transmission a useful risk indicator?

BACKGROUND: The presence of ongoing local malaria transmission, identified though local surveillance and reported to regional WHO offices, by S-E Asian countries, forms the basis of national and international chemoprophylaxis recommendations in western countries. The study was designed to examine whether the strategy of using malaria transmission in a local population was an accurate estimate of the malaria threat faced by travellers and a correlate of malaria in returning travellers. METHODS: Malaria endemicity was described from distribution and intensity in the local populations of ten S-E Asian destination countries over the period 2003-2008 from regionally reported cases to WHO offices. Travel acquired malaria was collated from malaria surveillance reports from the USA and 12 European countries over the same period. The numbers of travellers visiting the destination countries was based on immigration and tourism statistics collected on entry of tourists to the destination countries. RESULTS: In the destination countries, mean malaria rates in endemic countries ranged between 0.01 in Korea to 4:1000 population per year in Lao PDR, with higher regional rates in a number of countries. Malaria cases imported into the 13 countries declined by 47% from 140 cases in 2003 to 66 in 2008. A total of 608 cases (27.3% Plasmodium falciparum (Pf)) were reported over the six years, the largest number acquired in Indonesia, Thailand and Korea. Four countries had an incidence > 1 case per 100,000 traveller visits; Burma (Myanmar), Indonesia, Cambodia and Laos (range 1 to 11.8-case per 100,000 visits). The remaining six countries rates were 1 case per 100,000 visits to consider targeted malaria prophylaxis recommendations to minimize use of chemoprophylaxis for low risk exposure during visits to S-E Asia. Policy needs to be adjusted regularly to reflect the changing risk

The low and declining risk of malaria in travellers to Latin America: is there still an indication for chemoprophylaxis?

A comparison was made between local malaria transmission and malaria imported by travellers to identify the utility of national and regional annual parasite index (API) in predicting malaria risk and its value in generating recommendations on malaria prophylaxis for travellers

Diagnosis and follow-up of treatment of latent tuberculosis; the utility of the QuantiFERON-TB Gold In-tube assay in outpatients from a tuberculosis low-endemic country

<p>Abstract</p> <p>Background</p> <p>Interferon-gamma (IFN-γ) Release Assays (IGRA) are more specific than the tuberculosis skin test (TST) in the diagnosis of latent tuberculosis (TB) infection (LTBI). We present the performance of the QuantiFERON^®-TB Gold In-tube (QFT-TB) assay as diagnostic test and during follow-up of preventive TB therapy in outpatients from a TB low-endemic country.</p> <p>Methods</p> <p>481 persons with suspected TB infection were tested with QFT-TB. Thoracic X-ray and sputum samples were performed and a questionnaire concerning risk factors for TB was filled. Three months of isoniazid and rifampicin were given to patients with LTBI and QFT-TB tests were performed after three and 15 months.</p> <p>Results</p> <p>The QFT-TB test was positive in 30.8% (148/481) of the total, in 66.9% (111/166) of persons with origin from a TB endemic country, in 71.4% (20/28) previously treated for TB and in 100% (15/15) of those diagnosed with active TB with no inconclusive results. The QFT-TB test was more frequently positive in those with TST ≥ 15 mm (47.5%) compared to TST 11-14 mm (21.3%) and TST 6-10 mm (10.5%), (p < 0.001). Origin from a TB endemic country (OR 6.82, 95% CI 1.73-26.82), recent stay in a TB endemic country (OR 1.32, 95% CI 1.09-1.59), duration of TB exposure (OR 1.59, 95% CI 1.14-2.22) and previous TB disease (OR 11.60, 95% CI 2.02-66.73) were all independently associated with a positive QFT-TB test. After preventive therapy, 35/40 (87.5%) and 22/26 (84.6%) were still QFT-TB positive after three and 15 months, respectively. IFN-γ responses were comparable at start (mean 6.13 IU/ml ± SD 3.99) and after three months (mean 5.65 IU/ml ± SD 3.66) and 15 months (mean 5.65 IU/ml ± SD 4.14), (p > 0.05).</p> <p>Conclusion</p> <p>Only one third of those with suspected TB infection had a positive QFT-TB test. Recent immigration from TB endemic countries and long duration of exposure are risk factors for a positive QFT-TB test and these groups should be targeted through screening. Since most patients remained QFT-TB positive after therapy, the test should not be used to monitor the effect of preventive therapy. Prospective studies are needed in order to determine the usefulness of IGRA tests during therapy.</p

Pegylated interferon alfa and ribavirin for 14 versus 24 weeks in patients with hepatitis C virus genotype 2 or 3 and rapid virological response<sup/>

A recent nonrandomized pilot trial showed that hepatitis C virus (HCV) patients with genotype 2/3 and rapid virological response (RVR) had a 90% sustained virological response (SVR) rate after 14 weeks of treatment. We aimed to assess this concept in a randomized controlled trial. In the trial, 428 treatment-naive HCV RNA-positive patients with genotype 2 or 3 were enrolled. Patients with RVR were randomized to 14 (group A) or 24 (group B) weeks of treatment. Patients were treated with pegylated interferon alpha-26 (1.5 mu g/kg) subcutaneously weekly and ribavirin (800-1400 mg) orally daily. The noninferiority margin was set to be 10% between the two groups with a one-sided 2.5% significance level. RVR was obtained in 302 of 428 (71%), and 298 of these were randomized to group A (n = 148) or group B (n = 150). In the intention-to-treat analysis, SVR rates were 120 of 148 (81.1%) in group A and 136 of 150 (90.7%) in group B (difference, 9.6%; 95% confidence interval, 1.7-17.7). Among patients with an HCV RNA test 24 weeks after the end of treatment, 120 of 139 (86.3%) patients in group A achieved SVR compared with 136 of 146 (93.2%) in group B (difference, 6.9%; 95% confidence interval, -0.1 to + 13.9). Conclusion: We cannot formally claim that 14 weeks of treatment is noninferior to 24 weeks of treatment. However, the SVR rate after 14 weeks of treatment is high, and although longer treatment may give slightly better SVR, we believe economical savings and fewer side effects make it rational to treat patients with genotype 2 or 3 and RVR for only 14 weeks

Total imported malaria from 9 countries stratified by US and Non US reporting countries 2000–2005

<p><b>Copyright information:</b></p><p>Taken from "The low and declining risk of malaria in travellers to Latin America: is there still an indication for chemoprophylaxis?"</p><p>http://www.malariajournal.com/content/6/1/114</p><p>Malaria Journal 2007;6():114-114.</p><p>Published online 23 Aug 2007</p><p>PMCID:PMC2020466.</p><p></p