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33 result(s)
Journal Article > ResearchFull Text

The genetic diversity of Nipah virus across spatial scales

J Infect Dis. 16 December 2024; Volume 230 (Issue 6); e1235-e1244.; DOI:10.1093/infdis/jiae221
Cortes-Azuero O, Lefrancq N, Nikolay B, McKee C, Cappelle J,  et al.
J Infect Dis. 16 December 2024; Volume 230 (Issue 6); e1235-e1244.; DOI:10.1093/infdis/jiae221

BACKGROUND

Nipah virus (NiV), a highly lethal virus in humans, circulates in Pteropus bats throughout South and Southeast Asia. Difficulty in obtaining viral genomes from bats means we have a poor understanding of NiV diversity.


METHODS

We develop phylogenetic approaches applied to the most comprehensive collection of genomes to date (N = 257, 175 from bats, 73 from humans) from 6 countries over 22 years (1999–2020). We divide the 4 major NiV sublineages into 15 genetic clusters. Using Approximate Bayesian Computation fit to a spatial signature of viral diversity, we estimate the presence and the average size of genetic clusters per area.


RESULTS

We find that, within any bat roost, there are an average of 2.4 co-circulating genetic clusters, rising to 5.5 clusters at areas of 1500–2000 km2. We estimate that each genetic cluster occupies an average area of 1.3 million km2 (95% confidence interval [CI], .6–2.3 million km2), with 14 clusters in an area of 100 000 km2 (95% CI, 6–24 km2). In the few sites in Bangladesh and Cambodia where genomic surveillance has been concentrated, we estimate that most clusters have been identified, but only approximately 15% of overall NiV diversity has been uncovered.


CONCLUSIONS

Our findings are consistent with entrenched co-circulation of distinct lineages, even within roosts, coupled with slow migration over larger spatial scales.

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Journal Article > ResearchFull Text

Outcomes for efavirenz versus nevirapine-containing regimens for treatment of HIV-1 infection: A systematic review and meta-analysis

PLOS One. 22 July 2013; Volume 8 (Issue 7); e68995.; DOI:10.1371/journal.pone.0068995
Pillay P, Ford NP, Shubber Z, Ferrand RA
PLOS One. 22 July 2013; Volume 8 (Issue 7); e68995.; DOI:10.1371/journal.pone.0068995
Français
INTRODUCTION
There is conflicting evidence and practice regarding the use of the non-nucleoside reverse transcriptase inhibitors (NNRTI) efavirenz (EFV) and nevirapine (NVP) in first-line antiretroviral therapy (ART).

METHODS
We systematically reviewed virological outcomes in HIV-1 infected, treatment-naive patients on regimens containing EFV versus NVP from randomised trials and observational cohort studies. Data sources include PubMed, Embase, the Cochrane Central Register of Controlled Trials and conference proceedings of the International AIDS Society, Conference on Retroviruses and Opportunistic Infections, between 1996 to May 2013. Relative risks (RR) and 95% confidence intervals were synthesized using random-effects meta-analysis. Heterogeneity was assessed using the I(2) statistic, and subgroup analyses performed to assess the potential influence of study design, duration of follow up, location, and tuberculosis treatment. Sensitivity analyses explored the potential influence of different dosages of NVP and different viral load thresholds.

RESULTS
Of 5011 citations retrieved, 38 reports of studies comprising 114 391 patients were included for review. EFV was significantly less likely than NVP to lead to virologic failure in both trials (RR 0.85 [0.73-0.99] I(2) = 0%) and observational studies (RR 0.65 [0.59-0.71] I(2) = 54%). EFV was more likely to achieve virologic success than NVP, though marginally significant, in both randomised controlled trials (RR 1.04 [1.00-1.08] I(2) = 0%) and observational studies (RR 1.06 [1.00-1.12] I(2) = 68%).

CONCLUSION
EFV-based first line ART is significantly less likely to lead to virologic failure compared to NVP-based ART. This finding supports the use of EFV as the preferred NNRTI in first-line treatment regimen for HIV treatment, particularly in resource limited settings.
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Journal Article > ResearchFull Text

CMV retinitis in China and SE Asia: the way forward

BMC Infect Dis. 24 November 2011; Volume 11 (Issue 1); DOI:10.1186/1471-2334-11-327
Heiden D, Saranchuk P
BMC Infect Dis. 24 November 2011; Volume 11 (Issue 1); DOI:10.1186/1471-2334-11-327
AIDS-related CMV retinitis is a common clinical problem in patients with advanced HIV/AIDS in China and Southeast Asia. The disease is causing blindness, and current clinical management, commonly characterized by delayed diagnosis and inadequate treatment, results in poor clinical outcomes: 21% - 36% of eyes with CMV retinitis are already blind at the time the diagnosis is first established by an ophthalmologist. CMV retinitis also identifies a group of patients at extraordinary risk of mortality, and the direct or indirect contribution of extraocular CMV disease to AIDS-related morbidity and mortality is currently unmeasured and clinically often overlooked. The obvious way to improve clinical management of CMV retinitis is to screen all patients with CD4 counts < 100 cells/μL with indirect ophthalmoscopy at the time they first present for care, and to provide systemic treatment with oral valganciclovir when active CMV retinitis is detected. Treatment of opportunistic infections is an integral part of HIV management, and, with appropriate training and support, CMV retinitis screening and treatment can be managed by the HIV clinicians, like all other opportunistic infections. Access to ophthalmologist has been problematic for HIV patients in China, and although non-ophthalmologists can perform screening, sophisticated ophthalmological skills are required for the management of retinal detachment and immune recovery uveitis, the major complications of CMV retinitis. CMV retinitis has been clinically ignored, in part, because of the perceived complexity and expense of treatment, and this obstacle can be removed by making valganciclovir affordable and widely available. Valganciclovir is an essential drug for developing successful programs for management of CMV retinitis in China and throughout SE Asia.More
Journal Article > ResearchFull Text

Tuberculosis treatment in a refugee and migrant population: 20 years of experience on the Thai-Burmese border

Int J Tuberc Lung Dis. 1 December 2010; Volume 14 (Issue 12); 1589-1595.
Minetti A, Camelique O, Hsa Thaw K, Thi SS, Swaddiwudhipong W,  et al.
Int J Tuberc Lung Dis. 1 December 2010; Volume 14 (Issue 12); 1589-1595.
SETTING
Although tuberculosis (TB) is a curable disease, it remains a major global health problem and an important cause of morbidity and mortality among vulnerable populations, including refugees and migrants.

OBJECTIVE
To describe results and experiences over 20 years at a TB programme in refugee camps on the Thai-Burmese border in Tak Province, Thailand, and to identify risk factors associated with adverse outcomes (e.g., default, failure, death).

DESIGN
Retrospective review of routine records of 2425 patients admitted for TB treatment in the Mae La TB programme between May 1987 and December 2005.

RESULTS
TB cases notified among refugees decreased over 20 years. Among patients treated with a first-, second- or third-line regimen, 77.5% had a successful outcome, 13.5% defaulted, 7.6% died and 1.3% failed treatment. Multivariate analysis for new cases showed higher likelihood of adverse outcomes for patients who were Burmese migrants or Thai villagers, male, aged >15 years or with smear-negative pulmonary TB.

CONCLUSION
These findings suggest that treatment outcomes depend on the programme's capacity to respond to specific patients' constraints. High-risk groups, such as migrant populations, need a patient-centred approach, and specific, innovative strategies have to be developed based on the needs of the most vulnerable and marginalised populations.
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Journal Article > ResearchFull Text

Comparison of chloroquine, sulfadoxine/pyrimethamine, mefloquine and mefloquine-artesunate for the treatment of falciparum malaria in Kachin State, North Myanmar

Trop Med Int Health. 1 November 2004; Volume 9 (Issue 11); 1184-1190.; DOI:10.1111/j.1365-3156.2004.01323.x
Smithuis FM, Shahmanesh M, Kyaw MK, Savran O, Lwin S,  et al.
Trop Med Int Health. 1 November 2004; Volume 9 (Issue 11); 1184-1190.; DOI:10.1111/j.1365-3156.2004.01323.x
Multi-drug resistant falciparum malaria is widespread in Asia. In Thailand, Cambodia and Vietnam the national protocols have changed largely to artesunate combined treatment regimens but elsewhere in East and South Asia chloroquine (CQ) and sulfadoxine-pyrimethamine (SP) are still widely recommended by national malaria control programmes. In Kachin State, northern Myanmar, an area of low seasonal malaria transmission, the efficacy of CQ (25 mg base/kg) and SP (1.25/25 mg/kg), the nationally recommended treatments at the time, were compared with mefloquine alone (M; 15 mg base/kg) and mefloquine combined with artesunate (MA; 15:4 mg/kg). An open randomized controlled trial enrolled 316 patients with uncomplicated Plasmodium falciparum malaria, stratified prospectively into three age-groups. Early treatment failures (ETF) occurred in 41% (32/78) of CQ treated patients and in 24% of patients treated with SP (18/75). In young children the ETF rates were 87% after CQ and 35% after SP. Four children (two CQ, two SP) developed symptoms of cerebral malaria within 3 days after treatment. By day 42, failure rates (uncorrected for reinfections) had increased to 79% for CQ and 81% for SP. ETF rates were 2.5% after treatment with M and 3.9% after treatment with MA (P > 0.2). Overall uncorrected treatment failure rates at day 42 following M and MA were 23% and 21%, respectively. Chloroquine and SP are completely ineffective for the treatment of falciparum malaria in northern Myanmar. Mefloquine treatment is much more effective, but three day combination regimens with artesunate will be needed for optimum efficacy and protection against resistance.More
Journal Article > LetterFull Text

Zidovudine to prevent mother-to-infant HIV transmission in developing countries: a view from Thailand

Trop Med Int Health. 1 March 1999; Volume 4 (Issue 3); 236-238.; DOI:10.1046/j.1365-3156.1999.43384.x
Kumphitak A, Cawthorne P, Lakhonphol S, Kasi-Sedapan S, Sanaeha S,  et al.
Trop Med Int Health. 1 March 1999; Volume 4 (Issue 3); 236-238.; DOI:10.1046/j.1365-3156.1999.43384.x
Journal Article > ResearchAbstract

Viral Load Monitoring as a Tool to Reinforce Adherence: A Systematic Review

J Acquir Immune Defic Syndr. 14 June 2013; Volume 64 (Issue 1); DOI:10.1097/QAI.0b013e31829f05ac
Bonner K, Mezochow A, Roberts TR, Ford NP, Cohn J
J Acquir Immune Defic Syndr. 14 June 2013; Volume 64 (Issue 1); DOI:10.1097/QAI.0b013e31829f05ac
Viral load monitoring has been proposed as a tool to reinforce adherence, but outcomes have never been systematically assessed.
Journal Article > ResearchFull Text

Treatment outcomes of patients on Second-line Antiretroviral Therapy in resource-limited settings: A Systematic Review and Meta-Analysis

AIDS. 15 May 2012; Volume 26 (Issue 8); DOI:10.1097/QAD.0b013e328351f5b2
Ajose O, Mookerjee S, Mills EJ, Boulle AM, Ford NP
AIDS. 15 May 2012; Volume 26 (Issue 8); DOI:10.1097/QAD.0b013e328351f5b2
A growing proportion of patients on antiretroviral therapy in resource-limited settings have switched to second-line regimens. We carried out a systematic review in order to summarize reported rates and reasons for virological failure among people on second-line therapy in resource-limited settings.More
Journal Article > ResearchFull Text

Field evaluation of a simple fluorescence method for detection of viable Mycobacterium tuberculosis in sputum specimens during treatment follow-up

J Clin Microbiol. 30 May 2012; Volume 50 (Issue 8); DOI:10.1128/JCM.01232-12
Schramm B, Hewison CCH, Bonte L, Jones W, Camelique O,  et al.
J Clin Microbiol. 30 May 2012; Volume 50 (Issue 8); DOI:10.1128/JCM.01232-12
Simple tuberculosis (TB) treatment monitoring tools are needed. We assessed the performance of fluorescein-diacetate (FDA) smear microscopy for detection of viable Mycobacterium tuberculosis in sputum specimens (n = 288) of TB cases under treatment compared to culture (17.4% culture positivity). FDA sensitivity was moderate (83.7% [95% confidence interval {CI}, 70.3 to 92.6]), and specificity was low (66.1% [59.5 to 72.2]). The good negative predictive value (94.8% [90.1 to 97.8]) and negative likelihood ratio (0.2) suggest using this method to rule out treatment failure in settings without access to culture.More
Journal Article > ResearchFull Text

Relapses of Plasmodium vivax infection usually result from activation of heterologous hypnozoites

J Infect Dis. 1 April 2007; Volume 195 (Issue 7); DOI:10.1086/512241
Imwong M, Snounou G, Pukrittayakamee S, Tanomsing N, Kim JH,  et al.
J Infect Dis. 1 April 2007; Volume 195 (Issue 7); DOI:10.1086/512241
BACKGROUND: Relapses originating from hypnozoites are characteristic of Plasmodium vivax infections. Thus, reappearance of parasitemia after treatment can result from relapse, recrudescence, or reinfection. It has been assumed that parasites causing relapse would be a subset of the parasites that caused the primary infection. METHODS: Paired samples were collected before initiation of antimalarial treatment and at recurrence of parasitemia from 149 patients with vivax malaria in Thailand (n=36), where reinfection could be excluded, and during field studies in Myanmar (n=75) and India (n=38). RESULTS: Combined genetic data from 2 genotyping approaches showed that novel P. vivax populations were present in the majority of patients with recurrent infection (107 [72%] of 149 patients overall [78% of patients in Thailand, 75% of patients in Myanmar {Burma}, and 63% of patients in India]). In 61% of the Thai and Burmese patients and in 55% of the Indian patients, the recurrent infections contained none of the parasite genotypes that caused the acute infection. CONCLUSIONS: The P. vivax populations emerging from hypnozoites commonly differ from the populations that caused the acute episode. Activation of heterologous hypnozoite populations is the most common cause of first relapse in patients with vivax malaria.More