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Siddiqui, M. R.

Publications and source records attributed to Siddiqui, M. R..

2 recordsLinked to original sources

What drives mortality among HIV patients in a conflict setting? A prospective cohort study in the Central African Republic

BackgroundProvision of antiretroviral therapy (ART) during conflict settings is rarely attempted and little is known about the expected patterns of mortality. The Central African Republic (CAR) continues to have a low coverage of ART despite an estimated 120,000 people living with HIV and 11,000 AIDS-related deaths in 2013. We present results from a cohort in Zemio, Haut-Mboumou prefecture. This region had the highest prevalence of HIV nationally (14.8% in 2010) and was subject to repeated attacks by armed groups on civilians during the observed period.\n\nMethodsConflict from armed groups can impact cohort mortality rates i) directly if HIV patients are victims of armed conflict, or ii) indirectly if population displacement or fear of movement reduces access to ART. Using monthly counts of civilian deaths, injuries and abductions, we estimated the impact of the conflict on patient mortality. We also determine patient-level risk factors for mortality and how this varies with time spent in the cohort. Model-fitting was performed in a Bayesian framework, using generalised-linear models with terms accounting for temporal autocorrelation.\n\nResultsPatients were recruited and observed from October 2011 to May 2017. Overall 1631 patients were enrolled, giving 4107 person-years and 148 deaths. Our first model shows that patient mortality did not increase during periods of heightened conflict. The monthly risk (probability) of mortality was markedly higher at the beginning of the program (0.047 in November 2011 [95% credible interval; CrI 0.0078, 0.21]) and had declined greater than ten-fold by the end of the observed period (0.0016 in June 2017 [95% CrI 0.00042, 0.0036]). Our second model shows the risk of mortality for individual patients was highest in the first five months spent in the cohort. Male sex was associated with a higher mortality (odds ratio; OR 1.7 [95% CrI 1.2, 2.8]) along with the severity of opportunistic infections at baseline.\n\nConclusionsOur results show that chronic conflict did not appear to adversely affect rates of mortality in this cohort, and that mortality was driven predominantly by patient specific risk factors. In areas initiating ART for the first time, particular attention should be focussed on stabilising patients with advanced symptoms.\n\nFundingMedecins Sans Frontieres

epidemiology

Reactive and pre-emptive vaccination strategies to control hepatitis E infection in emergency and refugee settings: a modelling study.

BackgroundHepatitis E Virus (HEV) is an important cause of morbidity and mortality in emergency and refugee camp settings. Symptomatic infection is associated with case fatality rates of ~20% in pregnant women. However, its epidemiology is poorly understood and the potential impact of immunisation in outbreak settings uncertain. We aimed to estimate key epidemiological parameters for HEV and to evaluate the potential impact of both reactive vaccination (initiated in response to an epidemic) and pre-emptive vaccination.\n\nMethodsWe analysed data from one of the worlds largest recorded HEV epidemics, which occurred in refugee camps in Uganda (2007-2009), using transmission dynamic models to estimate epidemiological parameters and assess the potential impact of reactive and pre-emptive vaccination strategies.\n\nResultsUnder baseline assumptions we estimated the basic reproduction number of HEV to range from 3.9 (95% CrI 2.8, 5.4) to 8.9 (5.4, 14.2). Mean latent and infectious periods were estimated to be 34 (28, 39) and 40 (23, 71) days respectively.\n\nReactive two-dose vaccination of those aged 16-65 years excluding pregnant women (for whom vaccine is not licensed), if initiated after 50 reported cases, led to mean camp-specific reductions in mortality of 10 to 29%. Pre-emptive vaccination with two doses reduced mortality by 35 to 65%. Both strategies were more effective if coverage was extended to groups for whom the vaccine is not currently licensed. For example, two dose pre-emptive vaccination, if extended to include pregnant women, led to mean reductions in mortality of 66 to 82%.\n\nConclusionsHEV has a high transmission potential in refugee camp settings. Substantial reductions in mortality through vaccination are expected, even if used reactively. There is potential for greater impact if vaccine safety and effectiveness can be established in pregnant women.\n\nFundingWellcome Trust (106491/Z/14/Z and 089275/Z/09/Z). BC: MRC/DfID (MR/K006924/1).

epidemiology