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1.
Int J STD AIDS ; 19(5): 339-41, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18482966

RESUMO

The aim of this study was to determine HIV-1 incidence among women of reproductive age in Malawi. A prospective study design was followed. HIV-1 uninfected women were followed up for nine visits during a period of 12 months. At baseline, women received HIV-1 counselling and testing. At each visit, venous blood was collected for HIV-1 testing. Incidence rate for HIV-1 was estimated using person-years of follow up (PYFU). Risk factors for HIV acquisition were assessed using Cox proportional hazard models. A total of 842 HIV-1 negative women were enrolled in the study. Of these, 787 had subsequent HIV testing and 31 were found HIV-1 infected; an overall incidence rate of 4.51 (95% confidence interval: 2.96-6.06) per 100 PYFU was obtained. Young age, using hormonal injectable contraceptives and bacterial vaginosis were the main predictors of HIV acquisition. The incidence of HIV continues to be high among women in Malawi, and young women appear to be at higher risk.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , HIV-1/isolamento & purificação , Infecções Sexualmente Transmissíveis/epidemiologia , Anticoncepcionais , Feminino , Infecções por HIV/sangue , Infecções por HIV/etiologia , Infecções por HIV/virologia , Humanos , Incidência , Malaui/epidemiologia , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/prevenção & controle , Vaginose Bacteriana/epidemiologia
2.
AIDS ; 12(2): 197-203, 1998 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-9468369

RESUMO

OBJECTIVES: To examine rates of HIV-1 and sexually transmitted disease (STD) among pregnant and postpartum women in urban Malawi, Africa. DESIGN: Serial cross-sectional surveys and a prospective study. METHODS: Three major surveys were conducted in 1990, 1993 and 1994/1995. Consecutive first-visit antenatal women and women giving birth at the Queen Elizabeth Central Hospital were tested for HIV and STD after counseling and obtaining informed consent. Unlinked, anonymous HIV testing was also conducted on smaller samples of antenatal women in the same hospital to provide annual prevalence data. HIV-seronegative postpartum women from the 1990 and 1993 surveys were enrolled in a prospective study to determine HIV incidence. RESULTS: HIV seroprevalence rose from 2.0% in 1985 to 32.8% in 1996, a 16-fold increase. The highest age-specific HIV prevalence was in the following age-groups: 20-24 years during 1990, 25-29 years during 1993, and 30-34 years during 1996. Among 1173 women followed for a median of 30.9 months, HIV incidence was 5.98 per 100 person-years in women aged < 20 years and declined steadily in older women. The prevalence of STD significantly declined among both HIV-positive and negative women. This decline in STD prevalence, however, was not accompanied by increased condom use over time. CONCLUSIONS: Among urban childbearing women in Malawi, incidence of HIV is highest among young women while, currently, prevalence is highest among older women. Recent declines in STD prevalence suggest that HIV prevention programs are having an impact either through improved STD diagnosis and treatment or reduced risk behaviors. Sequential cross-sectional STD prevalence measures may be useful in monitoring effectiveness of STD and HIV prevention activities.


PIP: Prevalence rates of HIV-1 and other sexually transmitted diseases (STDs) among pregnant and postpartum women were investigated in sequential, cross-sectional studies (1990, 1993, and 1994-95) conducted at Queen Elizabeth Central Hospital in Blantyre, Malawi. Annual anonymous, unlinked testing revealed a linear increase in HIV-1 prevalence among antenatal patients from 2.0% in 1985 to 32.8% in 1996. Analysis of demographic attributes of women enrolled in the 1990 and 1993 surveys of consecutive, first-visit antenatal women (n = 6603 and 2161, respectively) and the 1994-95 study of all women giving birth at the hospital during a 6-month period (n = 6964) indicated that HIV-infected women were most likely to be young, with fewer pregnancies, and be more educated. The highest age-specific HIV prevalence shifted from 20-24 years in 1990 to 30-34 years in 1996, indicating an aging cohort of women who became infected at a younger age. Reported lifetime use of condoms increased from 5.6% in 1990 to 17.5% in 1993, then declined to 4.9% in 1995; condom use was consistently higher among HIV-positive than HIV-negative women. The prevalence of all STDs (syphilis, trichomoniasis, gonorrhea, and genital warts and ulcers) declined significantly during 1990-96, with the most consistent decreases recorded among HIV-positive women. In a follow-up study of 1173 HIV-seronegative, postpartum women evaluated for 2302 person-years (average duration, 30.9 months), 97 seroconverted (4.21/100 person-years). The seroconversion rate declined steadily from 21.26/100 person-years in 1990 to 1.11/100 person-years in 1994-95. These findings are consistent with those from other sub-Saharan African countries, indicating a rapid increase in HIV prevalence followed by stabilization within about 10 years of the onset of the epidemic. The large decline in STD prevalence in the antenatal population suggests that Malawi's national AIDS prevention program is having an impact, either through improved STD diagnosis and treatment or reduced risk behaviors.


Assuntos
Infecções por HIV/epidemiologia , HIV-1 , Complicações Infecciosas na Gravidez/epidemiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Adulto , Preservativos , Estudos Transversais , Coleta de Dados , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/prevenção & controle , Soroprevalência de HIV , Humanos , Incidência , Malaui/epidemiologia , Pessoa de Meia-Idade , Período Pós-Parto , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Prevalência , Estudos Prospectivos , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/prevenção & controle
3.
AIDS ; 14(4): 453-9, 2000 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-10770550

RESUMO

OBJECTIVE: To examine the association of viral load and CD4 lymphocyte count with mortality among HIV-infected children over one year of age. DESIGN: A prospective study. HIV-infected children were enrolled during the first year of life and followed for more than 2 years at the Queen Elizabeth Central Hospital in Blantyre, Malawi (southeast Africa). METHODS: Morbidity and mortality information was collected every 3 months, and physical examination and blood testing (for viral level and CD4 cell percentage) were performed every 6 months. Kaplan-Meier analyses and proportional hazards models were used to estimate survival and to examine the association of primary predictors with mortality. RESULTS: Of 155 HIV-infected children originally enrolled, 115 (74%) had viral load testing and 82 (53%) had both viral load and CD4 cell percentage testing after their first year. Among children over one year of age, significant associations were found between mortality and the log10 viral load and CD4 cell percentage in both univariate and multivariate models. Independent of the CD4 cell value, a one unit log10 increase in HIV RNA level increased the hazard of child mortality by more than twofold. Children with low CD4 cell counts (< 15%) and high viral loads (> or = 250,000 copies/ml median value) had the worst survival; children with high CD4 cell counts (> or = 15%) and low viral loads (< 250,000 copies/ml) had the best survival. CONCLUSION: As in developed countries, viral load and CD4 cell count are the main predictors of mortality among African children. Making these tests available adds to the challenges to be considered if antiviral therapies were to be adopted in these countries.


Assuntos
Contagem de Linfócito CD4 , Infecções por HIV/imunologia , Infecções por HIV/virologia , Análise de Sobrevida , Carga Viral , Pré-Escolar , Feminino , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas , Malaui/epidemiologia , Masculino , Estudos Prospectivos
4.
AIDS ; 12(13): 1699-706, 1998 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-9764791

RESUMO

BACKGROUND: Cross-sectional studies suggest an association between bacterial vaginosis (BV) and HIV-1 infection. However, an assessment of a temporal effect was not possible. OBJECTIVES: To determine the association of BV and other disturbances of vaginal flora with HIV seroconversion among pregnant and postnatal women in Malawi, Africa. DESIGN: Longitudinal follow-up of pregnant and postpartum women. METHODS: Women attending their first antenatal care visit were screened for HIV after counselling and obtaining informed consent. HIV-seronegative women were enrolled and followed during pregnancy and after delivery. These women were again tested for HIV at delivery and at 6-monthly visits postnatally. Clinical examinations and collection of laboratory specimens (for BV and sexually transmitted diseases) were conducted at screening and at the postnatal 6-monthly visits. The diagnosis of BV was based on clinical criteria. Associations of BV and other risk factors with HIV seroconversion, were examined using contingency tables and multiple logistic regression analyses on antenatal data, and Kaplan-Meier proportional hazards analyses on postnatal data. RESULTS: Among 1196 HIV-seronegative women who were followed antenatally for a median of 3.4 months, 27 women seroconverted by time of delivery. Postnatally, 97 seroconversions occurred among 1169 seronegative women who were followed for a median of 2.5 years. Bacterial vaginosis was significantly associated with antenatal HIV seroconversion (adjusted odds ratio = 3.7) and postnatal HIV seroconversion (adjusted rate ratio = 2.3). There was a significant trend of increased risk of HIV seroconversion with increasing severity of vaginal disturbance among both antenatal and postnatal women. The approximate attributable risk of BV alone was 23% for antenatal HIV seroconversions and 14% for postnatal seroconversions. CONCLUSIONS: This prospective study suggests that progressively greater disturbances of vaginal flora, increase HIV acquisition during pregnancy and postnatally. The screening and treating of women with BV could restore normal flora and reduce their susceptibility to HIV.


Assuntos
Infecções por HIV/complicações , HIV-1 , Complicações Infecciosas na Gravidez/microbiologia , Vagina/microbiologia , Vaginose Bacteriana/complicações , Estudos de Coortes , Estudos Transversais , Feminino , Infecções por HIV/microbiologia , Soroprevalência de HIV , Humanos , Estudos Longitudinais , Malaui/epidemiologia , Período Pós-Parto , Gravidez , Fatores de Risco
5.
Pediatr Infect Dis J ; 18(8): 689-94, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10462337

RESUMO

BACKGROUND: HIV-infected and uninfected children who survived their first year of life were prospectively followed in Malawi to assess levels of mortality and related risk factors during the second and third years of life. METHODS: Children with known HIV status from an earlier perinatal intervention trial were enrolled. These children [HIV-infected (Group A); HIV-uninfected but born to HIV-seropositive mothers (Group B); and children born to HIV-seronegative mothers (Group C)] were followed every 3 months until age 36 months. Mortality data were collected at each visit. Immunologic data (CD4+ percent) were collected at or immediately after enrollment. RESULTS: Overall 702 children were enrolled and 83 children died during follow-up. The mortality rate per 1000 person years of observation was 339.3 among Group A children, 46.3 among Group B children and 35.7 among Group C children. Among HIV-infected children the cumulative proportion surviving to age 24 months was 70% and those surviving to age 36 months was 55%. By age 32 months none of the severely immunosuppressed (CD4% < 15%) children had survived. The mortality differentials between HIV-infected and uninfected children persisted after adjusting for several risk factors. The major causes of death among infected children (n = 52) were wasting and respiratory conditions. CONCLUSIONS: Although all HIV-infected children had received childhood immunizations, mortality was high. Management of these children should include aggressive antimicrobial treatment, and evaluation of prophylactic regimens should be considered.


Assuntos
Infecções por HIV/mortalidade , HIV-1 , Adulto , Causas de Morte , Pré-Escolar , Feminino , Seguimentos , Infecções por HIV/transmissão , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Malaui/epidemiologia , Estudos Prospectivos , Fatores de Risco
6.
Int J STD AIDS ; 22(7): 368-72, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21729953

RESUMO

The expanding services of antiretroviral treatment (ART) in sub-Saharan Africa provide unique opportunities to reduce HIV/AIDS-related morbidity and mortality. In these settings, HIV prevalence among antenatal women remains high and treating eligible pregnant or breastfeeding women with antiretrovirals can substantially reduce transmission of HIV from the mother to her infant. However, identification of women eligible for treatment and ensuring access to ART services is challenging. In this analysis, we used data from a large clinical trial (the PEPI-Malawi study, 2004-09) to prevent mother-to-child transmission of HIV through extended antiretroviral prophylaxis of infants to examine barriers for wider coverage with highly active antiretroviral treatment (HAART) of postpartum women. Maternal HAART was not part of the original PEPI-Malawi clinical trial but became available through a government programme during the course of the study. Therefore, eligible women (CD4 cell count <250) who participated in the PEPI-Malawi trial were counselled and referred to the government ART clinics to initiate HAART. Of 3335 women who enrolled in the PEPI-Malawi study, 803 (24%) were eligible for HAART based on CD4 cell count. The proportion of women newly initiating HAART at the ART clinic remained low and constant (<20%) throughout the study period. However, the cumulative proportion of women receiving HAART increased substantially over time (29% in 2005 to 69% in 2009). Similarly, counselling and referral of eligible women substantially increased and became 100% during the last two years. There were no statistically significant differences in characteristics of eligible women who received or did not receive HAART postpartum. Despite limitations of not being able to obtain detailed data, the main barriers appeared to be related to the health-care system delivery of ART services. Issues of physical space, more personnel and better delivery need to be addressed to increase access to HAART in these settings.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Terapia Antirretroviral de Alta Atividade/métodos , Uso de Medicamentos/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , Adulto , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Malaui , Adesão à Medicação/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Período Pós-Parto , Gravidez
7.
J Acquir Immune Defic Syndr ; 27(2): 202-8, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11404543

RESUMO

OBJECTIVES: To determine incidence of HIV and associated risk factors in two cohorts of men working at a sugar estate in rural Malawi. DESIGN: Prospective studies. METHODS: After counseling and obtaining informed consent, male workers were tested for HIV-1 and syphilis. Baseline HIV-seronegative men were enrolled in two follow-up studies in 1994 and 1998, and were retested for HIV and syphilis at 6-month follow-up visits. Demographic, behavioral, and medical history was collected at baseline. Cumulative HIV incidence based on Kaplan-Meier methods was estimated. HIV incidence was also estimated per 100 person-years (p-y). Crude and adjusted rate ratios for the association of risk factors with incident HIV infection were obtained using Cox proportional hazards models. RESULTS: HIV prevalence was 24.3% among 1692 men screened in 1994 and 21.0% among 1349 men screened in 1998 (p <.03). HIV incidence was extremely high during 1994 to 1995 (17.1% for that 1-year period). Incidence dramatically declined in 1996, averaging about 3.5% per year from 1996 through 1999. Among men enrolled in the 1998 cohort, HIV incidence during 1998 to 1999 was 3.8%. After controlling for potential confounders reactive syphilis was associated with a twofold risk of HIV acquisition in each cohort. CONCLUSIONS: Urgent preventive measures are needed to control the spread of HIV in this economically important occupational cohort. In addition to conventional educational messages to reduce risky sexual behavior, treatment of other sexually transmitted diseases should be considered.


Assuntos
Doenças dos Trabalhadores Agrícolas/epidemiologia , Infecções por HIV/epidemiologia , População Rural , Adolescente , Adulto , Doenças dos Trabalhadores Agrícolas/virologia , Anticorpos Anti-HIV/sangue , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Incidência , Malaui/epidemiologia , Masculino , Pessoa de Meia-Idade , Sífilis/diagnóstico , Sífilis/epidemiologia
8.
Pediatrics ; 106(6): E77, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11099620

RESUMO

OBJECTIVE: To assess patterns of morbidity and associated factors in late infancy and early childhood among human immunodeficiency virus (HIV)-infected and -uninfected African children. DESIGN: Prospective study. SETTING: The Queen Elizabeth Central Hospital, Blantyre, Malawi. PARTICIPANTS: Children with known HIV status from an earlier perinatal intervention trial were enrolled during the first year of life and followed to approximately 36 months of age. OUTCOME MEASURES: Morbidity and mortality information was collected every 3 months by a questionnaire. A physical examination was conducted every 6 months. Blood to determine CD4(+) values was also collected. Age-adjusted and Kaplan-Meier analyses were performed to compare rates of morbidity and mortality among infected and uninfected children. RESULTS: Overall, 808 children (190 HIV-infected, 499 HIV-uninfected but born to infected mothers, and 119 born to HIV-uninfected mothers) were included in this study. Of these, 109 died during a median follow-up of 18 months. Rates of childhood immunizations were high among all children (eg, lowest was measles vaccination [87%] among HIV-infected children). Age-adjusted morbidity rates were significantly higher among HIV-infected than among HIV-uninfected children. HIV-infected children were more immunosuppressed than were uninfected children. By 3 years of age, 89% of the infected children died, 10% were in HIV disease category B or C, and only approximately 1% were without HIV symptoms. Among HIV-infected children, median survival after the first occurrence of acquired immunodeficiency syndrome-related conditions, such as splenomegaly, oral thrush, and developmental delay, was <10 months. These same conditions, in addition to frequent bouts of fever, were the main morbidity predictors of mortality. CONCLUSIONS: The frequency of diseases was high, and progression from asymptomatic or symptomatic HIV disease to death was rapid. Management strategies that effectively reduce morbidity for HIV-infected children are needed.


Assuntos
Síndrome da Imunodeficiência Adquirida/epidemiologia , HIV-1 , Síndrome da Imunodeficiência Adquirida/transmissão , África/epidemiologia , Distribuição por Idade , Relação CD4-CD8 , Candidíase Bucal/epidemiologia , Pré-Escolar , Doença Crônica , Comorbidade , Tosse/epidemiologia , Dermatite/epidemiologia , Diarreia/epidemiologia , Feminino , Febre/epidemiologia , Seguimentos , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas , Masculino , Otite/epidemiologia , Modelos de Riscos Proporcionais , Análise de Sobrevida , Taxa de Sobrevida , Subpopulações de Linfócitos T
9.
JAMA ; 282(8): 744-9, 1999 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-10463709

RESUMO

CONTEXT: Understanding the risk of human immunodeficiency virus (HIV) transmission through breastfeeding is essential for advising HIV-infected mothers and formulating public health policy recommendations. OBJECTIVE: To measure the frequency, timing, and risk factors of HIV transmission through breast milk. DESIGN: Prospective cohort study conducted between 1994 and 1997, with follow-up of infants through 24 months of age. SETTING: Postnatal clinic of tertiary care hospital, Blantyre, Malawi. PARTICIPANTS: A total of 672 infants (HIV-negative at birth) born to HIV-infected women who had not received antiretroviral drugs during or after pregnancy. MAIN OUTCOME MEASURE: Incidence of HIV in breastfed infants by age and maternal and infant risk factors for HIV transmission, using proportional hazard models to derive risk ratios (RRs) and 95% confidence intervals (CIs). RESULTS: Forty-seven children became HIV-infected while breastfeeding but none after breastfeeding had stopped. The cumulative infection rate while breastfeeding, from month 1 to the end of months 5, 11,17, and 23, was 3.5%, 7.0%, 8.9%, and 10.3%, respectively. Incidence per month was 0.7% during age 1 to 5 months, 0.6% during age 6 to 11 months, and 0.3% during age 12 to 17 months (P = .01 for trend). The only factors significantly associated with low risk of postnatal HIV transmission in a multivariate model were high maternal parity (RR, 0.23; 95% CI, 0.09-0.56) and older maternal age (RR, 0.44; 95% CI, 0.23-0.84). CONCLUSIONS: Our data suggest that the risk of HIV infection is highest in the early months of breastfeeding, which should be considered in formulating breastfeeding policy recommendations.


Assuntos
Aleitamento Materno , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas , Aleitamento Materno/efeitos adversos , Aleitamento Materno/estatística & dados numéricos , Feminino , Infecções por HIV/epidemiologia , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Malaui , Distribuição de Poisson , Gravidez , Complicações Infecciosas na Gravidez , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de Regressão , Risco , Fatores de Risco , Desmame
10.
Artigo em Inglês | MEDLINE | ID: mdl-9928730

RESUMO

Disturbances of vaginal flora are common among women of reproductive age. In areas of sub-Saharan Africa where the prevalence of HIV is high, the frequency of bacterial vaginosis (BV) is also high. In this study, we assessed the association of BV and other disturbances of vaginal flora with prevalent HIV infection in two cross-sectional studies among pregnant women in urban Malawi. The prevalence of HIV-1 was 23% in 1990 and 30% in 1993. Overall, 30% of the women had BV, 59% had mild or moderate disturbance of vaginal flora, and only 11% had normal vaginal flora. Increasing prevalence of HIV was significantly associated with increasing severity of disturbance of vaginal flora (p < .00001, chi2 trend test). This trend of increased prevalence persisted after controlling for concurrent sexually transmitted diseases (STDs), sexual activity, and socioeconomic factors. After multivariate adjustment for potential confounders, the odds ratio for the association of BV with prevalent HIV infection was 3.0 (95% confidence interval [CI], 2.4-3.8), that of moderate vaginal disturbance with HIV infection was 2.2 (95% CI, 1.7-2.8), and that of mild vaginal disturbance with HIV infection was 1.6 (95% CI, 1.3-2.1). Among women with BV, HIV infection was higher among younger women than older, implying more recent infection. Although these studies were cross-sectional, our data suggest that BV could be associated with increased susceptibility to HIV infection.


PIP: While ulcerative and nonulcerative STDs have been shown to be associated with HIV transmission, the potential association of HIV transmission with more frequent genital conditions which cause no inflammation of the vaginal or cervical mucosa have been inadequately studied. Bacterial vaginosis (BV) is characterized by disturbances in the vaginal flora resulting in the loss of lactobacilli, an increase in other mainly anaerobic flora, and an increased vaginal pH. Reproductive-age women commonly experience disturbances of vaginal flora, and in areas of sub-Saharan Africa in which HIV prevalence is high, there is also a high frequency of BV. The authors explored the association of BV and other disturbances of vaginal flora with prevalent HIV infection in 2 cross-sectional studies among pregnant women in urban Malawi. 23% of the 6684 women tested for HIV-1 infection in 1990 were seropositive, as well as 30% of 2464 women tested in 1993. Overall, 30% of the women had BV, 59% had mild or moderate disturbance of vaginal flora, and 11% had normal flora. An increasing prevalence of HIV was significantly associated with increasing severity of disturbance of vaginal flora, even after controlling for concurrent STDs, sexual activity, and socioeconomic factors. After multivariate adjustment for potential confounders, the odds ratio for the association of BV with prevalent HIV infection was 3.0, that of moderate vaginal disturbance with HIV infection was 2.2, and that of mild vaginal disturbance with HIV infection was 1.6. Among women with BV, HIV infection was higher among younger women than older, implying more recent infection. These findings suggest that BV could be associated with increased susceptibility to HIV infection.


Assuntos
Infecções por HIV/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Vagina/microbiologia , Vaginose Bacteriana/complicações , Adulto , Estudos Transversais , Feminino , Infecções por HIV/etiologia , Humanos , Gravidez , Prevalência
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