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1.
N Engl J Med ; 387(26): 2411-2424, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36516078

RESUMO

BACKGROUND: Questions remain concerning the rapidity of immune responses and the durability and safety of vaccines used to prevent Zaire Ebola virus disease. METHODS: We conducted two randomized, placebo-controlled trials - one involving adults and one involving children - to evaluate the safety and immune responses of three vaccine regimens against Zaire Ebola virus disease: Ad26.ZEBOV followed by MVA-BN-Filo 56 days later (the Ad26-MVA group), rVSVΔG-ZEBOV-GP followed by placebo 56 days later (the rVSV group), and rVSVΔG-ZEBOV-GP followed by rVSVΔG-ZEBOV-GP 56 days later (the rVSV-booster group). The primary end point was antibody response at 12 months, defined as having both a 12-month antibody concentration of at least 200 enzyme-linked immunosorbent assay units (EU) per milliliter and an increase from baseline in the antibody concentration by at least a factor of 4. RESULTS: A total of 1400 adults and 1401 children underwent randomization. Among both adults and children, the incidence of injection-site reactions and symptoms (e.g., feverishness and headache) was higher in the week after receipt of the primary and second or booster vaccinations than after receipt of placebo but not at later time points. These events were largely low-grade. At month 12, a total of 41% of adults (titer, 401 EU per milliliter) and 78% of children (titer, 828 EU per milliliter) had a response in the Ad26-MVA group; 76% (titer, 992 EU per milliliter) and 87% (titer, 1415 EU per milliliter), respectively, had a response in the rVSV group; 81% (titer, 1037 EU per milliliter) and 93% (titer, 1745 EU per milliliter), respectively, had a response in the rVSV-booster group; and 3% (titer, 93 EU per milliliter) and 4% (titer, 67 EU per milliliter), respectively, had a response in the placebo group (P<0.001 for all comparisons of vaccine with placebo). In both adults and children, antibody responses with vaccine differed from those with placebo beginning on day 14. CONCLUSIONS: No safety concerns were identified in this trial. With all three vaccine regimens, immune responses were seen from day 14 through month 12. (Funded by the National Institutes of Health and others; PREVAC ClinicalTrials.gov number, NCT02876328; EudraCT numbers, 2017-001798-18 and 2017-001798-18/3rd; and Pan African Clinical Trials Registry number, PACTR201712002760250.).


Assuntos
Vacinas contra Ebola , Ebolavirus , Doença pelo Vírus Ebola , Adulto , Criança , Humanos , Anticorpos Antivirais , República Democrática do Congo , Vacinas contra Ebola/uso terapêutico , Doença pelo Vírus Ebola/prevenção & controle
2.
Nature ; 575(7781): 119-129, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31695203

RESUMO

Vaccination against infectious diseases has changed the future of the human species, saving millions of lives every year, both children and adults, and providing major benefits to society as a whole. Here we show, however, that national and sub-national coverage of vaccination varies greatly and major unmet needs persist. Although scientific progress opens exciting perspectives in terms of new vaccines, the pathway from discovery to sustainable implementation can be long and difficult, from the financing, development and licensing to programme implementation and public acceptance. Immunization is one of the best investments in health and should remain a priority for research, industry, public health and society.


Assuntos
Desenvolvimento de Medicamentos/economia , Vacinação/tendências , Vacinas/imunologia , Vacinas/provisão & distribuição , Animais , Humanos , Mortalidade , Filipinas/epidemiologia , Mudança Social , Vacinação/economia , Vacinas/economia
3.
Nature ; 570(7760): 189-193, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31092927

RESUMO

HIV/AIDS is a leading cause of disease burden in sub-Saharan Africa. Existing evidence has demonstrated that there is substantial local variation in the prevalence of HIV; however, subnational variation has not been investigated at a high spatial resolution across the continent. Here we explore within-country variation at a 5 × 5-km resolution in sub-Saharan Africa by estimating the prevalence of HIV among adults (aged 15-49 years) and the corresponding number of people living with HIV from 2000 to 2017. Our analysis reveals substantial within-country variation in the prevalence of HIV throughout sub-Saharan Africa and local differences in both the direction and rate of change in HIV prevalence between 2000 and 2017, highlighting the degree to which important local differences are masked when examining trends at the country level. These fine-scale estimates of HIV prevalence across space and time provide an important tool for precisely targeting the interventions that are necessary to bringing HIV infections under control in sub-Saharan Africa.


Assuntos
Mapeamento Geográfico , Infecções por HIV/epidemiologia , Adolescente , Adulto , África Subsaariana/epidemiologia , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Saúde Pública/estatística & dados numéricos , Saúde Pública/tendências , Adulto Jovem
4.
BMC Med ; 18(1): 189, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32631314

RESUMO

BACKGROUND: HIV remains the largest cause of disease burden among men and women of reproductive age in sub-Saharan Africa. Voluntary medical male circumcision (VMMC) reduces the risk of female-to-male transmission of HIV by 50-60%. The World Health Organization (WHO) and Joint United Nations Programme on HIV/AIDS (UNAIDS) identified 14 priority countries for VMMC campaigns and set a coverage goal of 80% for men ages 15-49. From 2008 to 2017, over 18 million VMMCs were reported in priority countries. Nonetheless, relatively little is known about local variation in male circumcision (MC) prevalence. METHODS: We analyzed geo-located MC prevalence data from 109 household surveys using a Bayesian geostatistical modeling framework to estimate adult MC prevalence and the number of circumcised and uncircumcised men aged 15-49 in 38 countries in sub-Saharan Africa at a 5 × 5-km resolution and among first administrative level (typically provinces or states) and second administrative level (typically districts or counties) units. RESULTS: We found striking within-country and between-country variation in MC prevalence; most (12 of 14) priority countries had more than a twofold difference between their first administrative level units with the highest and lowest estimated prevalence in 2017. Although estimated national MC prevalence increased in all priority countries with the onset of VMMC campaigns, seven priority countries contained both subnational areas where estimated MC prevalence increased and areas where estimated MC prevalence decreased after the initiation of VMMC campaigns. In 2017, only three priority countries (Ethiopia, Kenya, and Tanzania) were likely to have reached the MC coverage target of 80% at the national level, and no priority country was likely to have reached this goal in all subnational areas. CONCLUSIONS: Despite MC prevalence increases in all priority countries since the onset of VMMC campaigns in 2008, MC prevalence remains below the 80% coverage target in most subnational areas and is highly variable. These mapped results provide an actionable tool for understanding local needs and informing VMMC interventions for maximum impact in the continued effort towards ending the HIV epidemic in sub-Saharan Africa.


Assuntos
Circuncisão Masculina/tendências , Infecções por HIV/prevenção & controle , Adolescente , Adulto , África , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
5.
J Infect Dis ; 217(2): 223-231, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29253164

RESUMO

The first reported outbreak of Ebola virus disease occurred in 1976 in Yambuku, Democratic Republic of Congo. Antibody responses in survivors 11 years after infection have been documented. However, this report is the first characterization of anti-Ebola virus antibody persistence and neutralization capacity 40 years after infection. Using ELISAs we measured survivor's immunological response to Ebola virus Zaire (EBOV) glycoprotein and nucleoprotein, and assessed VP40 reactivity. Neutralization of EBOV was measured using a pseudovirus approach and plaque reduction neutralization test with live EBOV. Some survivors from the original EBOV outbreak still harbor antibodies against all 3 measures. Interestingly, a subset of these survivors' serum antibodies could still neutralize live virus 40 years postinitial infection. These data provide the longest documentation of both anti-Ebola serological response and neutralization capacity within any survivor cohort, extending the known duration of response from 11 years postinfection to at least 40 years after symptomatic infection.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Surtos de Doenças , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/imunologia , República Democrática do Congo/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Inquéritos e Questionários , Sobreviventes , Fatores de Tempo , Ensaio de Placa Viral , Adulto Jovem
6.
Lancet ; 390(10113): 2662-2672, 2017 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-29031848

RESUMO

BACKGROUND: Predicting when and where pathogens will emerge is difficult, yet, as shown by the recent Ebola and Zika epidemics, effective and timely responses are key. It is therefore crucial to transition from reactive to proactive responses for these pathogens. To better identify priorities for outbreak mitigation and prevention, we developed a cohesive framework combining disparate methods and data sources, and assessed subnational pandemic potential for four viral haemorrhagic fevers in Africa, Crimean-Congo haemorrhagic fever, Ebola virus disease, Lassa fever, and Marburg virus disease. METHODS: In this multistage analysis, we quantified three stages underlying the potential of widespread viral haemorrhagic fever epidemics. Environmental suitability maps were used to define stage 1, index-case potential, which assesses populations at risk of infection due to spillover from zoonotic hosts or vectors, identifying where index cases could present. Stage 2, outbreak potential, iterates upon an existing framework, the Index for Risk Management, to measure potential for secondary spread in people within specific communities. For stage 3, epidemic potential, we combined local and international scale connectivity assessments with stage 2 to evaluate possible spread of local outbreaks nationally, regionally, and internationally. FINDINGS: We found epidemic potential to vary within Africa, with regions where viral haemorrhagic fever outbreaks have previously occurred (eg, western Africa) and areas currently considered non-endemic (eg, Cameroon and Ethiopia) both ranking highly. Tracking transitions between stages showed how an index case can escalate into a widespread epidemic in the absence of intervention (eg, Nigeria and Guinea). Our analysis showed Chad, Somalia, and South Sudan to be highly susceptible to any outbreak at subnational levels. INTERPRETATION: Our analysis provides a unified assessment of potential epidemic trajectories, with the aim of allowing national and international agencies to pre-emptively evaluate needs and target resources. Within each country, our framework identifies at-risk subnational locations in which to improve surveillance, diagnostic capabilities, and health systems in parallel with the design of policies for optimal responses at each stage. In conjunction with pandemic preparedness activities, assessments such as ours can identify regions where needs and provisions do not align, and thus should be targeted for future strengthening and support. FUNDING: Paul G Allen Family Foundation, Bill & Melinda Gates Foundation, Wellcome Trust, UK Department for International Development.


Assuntos
Febres Hemorrágicas Virais/epidemiologia , Pandemias , África/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Epidemias/estatística & dados numéricos , Humanos , Pandemias/estatística & dados numéricos , Medição de Risco
9.
AIDS Care ; 30(1): 103-115, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28679283

RESUMO

Non-communicable diseases (NCDs), including cardiovascular diseases (CVD), hypertension and diabetes together with HIV infection are among the major public health concerns worldwide. Health services for HIV and NCDs require health systems that provide for people's chronic care needs, which present an opportunity to coordinate efforts and create synergies between programs to benefit people living with HIV and/or AIDS and NCDs. This review included studies that reported service integration for HIV and/or AIDS with coronary heart diseases, chronic CVD, cerebrovascular diseases (stroke), hypertension or diabetes. We searched multiple databases from inception until October 2015. Articles were screened independently by two reviewers and assessed for risk of bias. 11,057 records were identified with 7,616 after duplicate removal. After screening titles and abstracts, 14 papers addressing 17 distinct interventions met the inclusion criteria. We categorized integration models by diseases (HIV with diabetes, HIV with hypertension and diabetes, HIV with CVD and finally HIV with hypertension and CVD and diabetes). Models also looked at integration from micro (patient focused integration) to macro (system level integrations). Most reported integration of hypertension and diabetes with HIV and AIDS services and described multidisciplinary collaboration, shared protocols, and incorporating screening activities into community campaigns. Integration took place exclusively at the meso-level, with no micro- or macro-level integrations described. Most were descriptive studies, with one cohort study reporting evaluative outcomes. Several innovative initiatives were identified and studies showed that CVD and HIV service integration is feasible. Integration should build on existing protocols and use the community as a locus for advocacy and health services, while promoting multidisciplinary teams, including greater involvement of pharmacists. There is a need for robust and well-designed studies at all levels - particularly macro-level studies, research looking at long-term outcomes of integration, and research in a more diverse range of countries.


Assuntos
Doenças Cardiovasculares/terapia , Doença Crônica/terapia , Prestação Integrada de Cuidados de Saúde/métodos , Prestação Integrada de Cuidados de Saúde/organização & administração , Diabetes Mellitus Tipo 2/terapia , Infecções por HIV/complicações , Hipertensão/terapia , Doenças Cardiovasculares/complicações , Diabetes Mellitus Tipo 2/complicações , Infecções por HIV/terapia , Humanos , Hipertensão/complicações
11.
J Infect Dis ; 214(suppl 3): S93-S101, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27357339

RESUMO

BACKGROUND: In 1976, the first cases of Ebola virus disease in northern Democratic Republic of the Congo (then referred to as Zaire) were reported. This article addresses who was responsible for recognizing the disease; recovering, identifying, and naming the virus; and describing the epidemic. Key scientific approaches used in 1976 and their relevance to the 3-country (Guinea, Sierra Leone, and Liberia) West African epidemic during 2013-2016 are presented. METHODS: Field and laboratory investigations started soon after notification, in mid-September 1976, and included virus cell culture, electron microscopy (EM), immunofluorescence antibody (IFA) testing of sera, case tracing, containment, and epidemiological surveys. In 2013-2016, medical care and public health work were delayed for months until the Ebola virus disease epidemic was officially declared an emergency by World Health Organization, but research in pathogenesis, clinical presentation, including sequelae, treatment, and prevention, has increased more recently. RESULTS: Filoviruses were cultured and observed by EM in Antwerp, Belgium (Institute of Tropical Medicine); Porton Down, United Kingdom (Microbiological Research Establishment); and Atlanta, Georgia (Centers for Disease Control and Prevention). In Atlanta, serological testing identified a new virus. The 1976 outbreak (280 deaths among 318 cases) stopped in <11 weeks, and basic clinical and epidemiological features were defined. The recent massive epidemic during 2013-2016 (11 310 deaths among 28 616 cases) has virtually stopped after >2 years. Transmission indices (R0) are higher in all 3 countries than in 1976. CONCLUSIONS: An international commission working harmoniously in laboratories and with local communities was essential for rapid success in 1976. Control and understanding of the recent West African outbreak were delayed because of late recognition and because authorities were overwhelmed by many patients and poor community involvement. Despite obstacles, research was a priority in 1976 and recently.


Assuntos
Surtos de Doenças/prevenção & controle , Ebolavirus/isolamento & purificação , Epidemias/prevenção & controle , Doença pelo Vírus Ebola/epidemiologia , Bélgica , Centers for Disease Control and Prevention, U.S. , República Democrática do Congo/epidemiologia , Ebolavirus/imunologia , Ebolavirus/ultraestrutura , Feminino , Georgia , Guiné/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Humanos , Libéria/epidemiologia , Masculino , Saúde Pública , Serra Leoa/epidemiologia , Reino Unido , Estados Unidos , Organização Mundial da Saúde
12.
PLoS Med ; 13(5): e1002042, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27195954

RESUMO

Lawrence Gostin and colleagues offer a set of priorities for global health preparedness and response for future infectious disease threats.


Assuntos
Saúde Global , Doença pelo Vírus Ebola/prevenção & controle , Cooperação Internacional , Programas Nacionais de Saúde , Saúde Pública , Pesquisa
17.
Lancet ; 384(9939): 272-9, 2014 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-24740087

RESUMO

Large declines in HIV incidence have been reported since 2001, and scientific advances in HIV prevention provide strong hope to reduce incidence further. Now is the time to replace the quest for so-called silver bullets with a public health approach to combination prevention that understands that risk is not evenly distributed and that effective interventions can vary by risk profile. Different countries have different microepidemics, with very different levels of transmission and risk groups, changing over time. Therefore, focus should be on high-transmission geographies, people at highest risk for HIV, and the package of interventions that are most likely to have the largest effect in each different microepidemic. Building on the backbone of behaviour change, condom use, and medical male circumcision, as well as expanded use of antiretroviral drugs for infected people and pre-exposure prophylaxis for uninfected people at high risk of infection, it is now possible to consider the prospect of what would be one of the most remarkable achievements in the history of public health: reduction of HIV transmission from a pandemic to low-level endemicity.


Assuntos
Doenças Endêmicas/estatística & dados numéricos , Infecções por HIV , Pandemias/prevenção & controle , Saúde Pública/métodos , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Masculino , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/terapia , Fatores de Risco
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