Eff ect of preventive and curative interventions on hepatitis C virus transmission in Egypt (ANRS 1211): a modelling study

Most hepatitis C virus (HCV) transmission in Egypt is related to medical injections and procedures. To control the spread of HCV, the Egyptian Ministry of Health initiated awareness and education campaigns, strengthened infection control in health-care facilities, and subsidised anti-HCV treatment. We aimed to investigate the effect of these interventions on the spread of HCV by mathematical modelling. Methods We developed a mathematical model of HCV transmission in Zawyat Razin, a typical rural community. Our model assumes that each individual has two distinct types of medical procedures: injections and more invasive medical procedures. To quantify the severity of the spread of HCV, we used the notion of the basic reproduction number R0, a standard threshold parameter signalling whether transmission of an infectious disease is self-sustained and maintains an epidemic. If R0 is greater than 1, HCV is self-sustained; if R0 is 1 or less, HCV transmission is not self-sustained. We investigated whether heterogeneity in the rate of injection or invasive medical procedures is the determinant factor for HCV transmission and whether most iatrogenic transmission is caused by a small group of individuals who receive health-care interventions frequently. We then assessed whether interventions targeted at this group could reduce the spread of HCV. Findings The R0 of the spread of HCV without treatment was 3·54 (95% CI 1·28–6·18), suggesting a self-sustained spread. Furthermore, the present national treatment programme only decreased R0 from 3·54 to 3·03 (95% CI 1·10–5·25). Individuals with high rates of medical injections seem to be responsible for the spread of HCV in Egypt; the R0 of the spread of HCV without treatment would be 0·64 (95% CI 0·41–0·93) if everybody followed the average behaviour. The effect of treatment on HCV transmission is greatly enhanced if treatment is provided a mean of 2·5 years (95% CI 0·1–9·2) after chronic infection and with drug regimens with more than 80% efficacy. With these treatment parameters, preventive and curative interventions targeting individuals with high rates of medical injections might decrease R0 below 1 for treatment coverage lower than 5%. Interpretation Targeting preventive and curative interventions to individuals with high rates of medical injections in Egypt would result in a greater reduction the spread of HCV than would untargeted allocation. Such an approach might prove beneficial in other resource-limited countries with health-care-driven epidemics

Exfoliation of graphene sheets via high energy wet milling of graphite in 2-ethylhexanol and kerosene

Graphene sheets have been exfoliated from bulk graphite using high energy wet milling in two different solvents that were 2-ethylhexanol and kerosene. The milling process was performed for 60 h using a planetary ball mill. Morphological characteristics were investigated using scanning electron microscope (SEM) and transmission electron microscope (TEM). On the other hand, the structural characterization was performed using X-ray diffraction technique (XRD) and Raman spectrometry. The exfoliated graphene sheets have represented good morphological and structural characteristics with a valuable amount of defects and a good graphitic structure. The graphene sheets exfoliated in the presence of 2-ethylhexanol have represented many layers, large crystal size and low level of defects, while the graphene sheets exfoliated in the presence of kerosene have represented fewer number of layers, smaller crystal size and higher level of defects

Excess mortality rate associated with hepatitis C virus infection: A community-based cohort study in rural Egypt

International audienceBackground & aims: >80% of people chronically infected with hepatitis C virus (HCV) live in resource-limited countries, yet the excess mortality associated with HCV infection in these settings is poorly documented.Methods: Individuals were recruited from three villages in rural Egypt in 1997-2003 and their vital status was determined in 2008-2009. Mortality rates across the cohorts were compared according to HCV status: chronic HCV infection (anti-HCV antibody positive and HCV RNA positive), cleared HCV infection (anti-HCV antibody positive and HCV RNA negative) and never infected (anti-HCV antibody negative). Data related to cause of death was collected from a death registry in one village.Results: Among 18,111 survey participants enrolled in 1997-2003, 9.1% had chronic HCV infection, 5.5% had cleared HCV infection, and 85.4% had never been infected. After a mean time to follow-up of 8.6years, vital status was obtained for 16,282 (89.9%) participants. When compared to those who had never been infected with HCV in the same age groups, mortality rate ratios (MRR) of males with chronic HCV infection aged <35, 35-44, and 45-54years were 2.35 (95% CI 1.00-5.49), 2.87 (1.46-5.63), and 2.22 (1.29-3.81), respectively. No difference in mortality rate was seen in older males or in females. The all-cause mortality rate attributable to chronic HCV infection was 5.7% (95% CI: 1.0-10.1%), while liver-related mortality was 45.5% (11.3-66.4%).Conclusions: Use of a highly potent new antiviral agent to treat all villagers with positive HCV RNA may reduce all-cause mortality rate by up to 5% and hepatic mortality by up to 40% in rural Egypt

Effect of preventive and curative interventions on hepatitis C virus transmission in Egypt (ANRS 1211): a modelling study

Background: Most hepatitis C virus (HCV) transmission in Egypt is related to medical injections and procedures. To control the spread of HCV, the Egyptian Ministry of Health initiated awareness and education campaigns, strengthened infection control in health-care facilities, and subsidised anti-HCV treatment. We aimed to investigate the effect of these interventions on the spread of HCV by mathematical modelling. Methods: We developed a mathematical model of HCV transmission in Zawyat Razin, a typical rural community. Our model assumes that each individual has two distinct types of medical procedures: injections and more invasive medical procedures. To quantify the severity of the spread of HCV, we used the notion of the basic reproduction number R0, a standard threshold parameter signalling whether transmission of an infectious disease is self-sustained and maintains an epidemic. If R0 is greater than 1, HCV is self-sustained; if R0 is 1 or less, HCV transmission is not self-sustained. We investigated whether heterogeneity in the rate of injection or invasive medical procedures is the determinant factor for HCV transmission and whether most iatrogenic transmission is caused by a small group of individuals who receive health-care interventions frequently. We then assessed whether interventions targeted at this group could reduce the spread of HCV. Findings: The R0 of the spread of HCV without treatment was 3·54 (95% CI 1·28–6·18), suggesting a self-sustained spread. Furthermore, the present national treatment programme only decreased R0 from 3·54 to 3·03 (95% CI 1·10–5·25). Individuals with high rates of medical injections seem to be responsible for the spread of HCV in Egypt; the R0 of the spread of HCV without treatment would be 0·64 (95% CI 0·41–0·93) if everybody followed the average behaviour. The effect of treatment on HCV transmission is greatly enhanced if treatment is provided a mean of 2·5 years (95% CI 0·1–9·2) after chronic infection and with drug regimens with more than 80% efficacy. With these treatment parameters, preventive and curative interventions targeting individuals with high rates of medical injections might decrease R0 below 1 for treatment coverage lower than 5%. Interpretation: Targeting preventive and curative interventions to individuals with high rates of medical injections in Egypt would result in a greater reduction the spread of HCV than would untargeted allocation. Such an approach might prove beneficial in other resource-limited countries with health-care-driven epidemics. Funding: Agence Nationale de Recherche sur le SIDA et les Hépatites Virales (ANRS 1211), ANR grant Labex Integrative Biology of Emerging Infectious Diseases

A Novel Method to Identify Routes of Hepatitis C Virus Transmission

<div><p>Background</p><p>We propose a new approach based on genetic distances among viral strains to infer about risk exposures and location of transmission at population level.</p><p>Methods</p><p>We re-analysed 133 viral sequences obtained during a cross-sectional survey of 4020 subjects living in a hepatitis C virus (HCV) endemic area in 2002. A permutation test was used to analyze the correlation between matrices of genetic distances in the NS5b region of all pairwise combinations of the 133 viral strains and exposure status (jointly exposed or not) to several potential HCV risk factors.</p><p>Results</p><p>Compared to subjects who did not share the same characteristics or iatrogenic exposures, the median Kimura genetic distances of viral strains were significantly smaller between brothers and sisters (0.031 versus 0.102, P<0.001), mother and child (0.044 versus 0.102, P<0.001), father and child (0.045 versus 0.102, P<0.001), or subjects exposed to periodontal treatment (0.084 versus 0.102, P = 0.02). Conversely, viral strains were more divergent between subjects exposed to blood transfusions (0.216 versus 0.102, P = 0.04) or tooth filling or extraction (0.108, versus 0.097, P = 0.05), suggesting acquisition of the virus outside of the village.</p><p>Conclusion</p><p>This method provided insights on where infection took place (household, village) for several socio-demographic characteristics or iatrogenic procedures, information of great relevance for targeting prevention interventions. This method may have interesting applications for virologists and epidemiologists studying transmission networks in health-care facilities or among intravenous drug users.</p></div

Pairwise E1 HCV genetic distances among 66 subjects according to common exposure patterns.

<p>doi:10.1371/journal.pone.0086098.t003</p

Pairwise NS5b HCV genetic distances among 133 subjects according to common exposure patterns.

<p>doi:10.1371/journal.pone.0086098.t002</p

Number of participants exposed to each risk factor.

<p>doi:10.1371/journal.pone.0086098.t001</p