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1.
Development ; 148(16)2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34387307

RESUMO

During early embryogenesis in amniotic vertebrates, the gonads differentiate into either ovaries or testes. The first cell lineage to differentiate gives rise to the supporting cells: Sertoli cells in males and pre-granulosa cells in females. These key cell types direct the differentiation of the other cell types in the gonad, including steroidogenic cells. The gonadal surface epithelium and the interstitial cell populations are less well studied, and little is known about their sexual differentiation programs. Here, we show the requirement of the homeobox transcription factor gene TGIF1 for ovarian development in the chicken embryo. TGIF1 is expressed in the two principal ovarian somatic cell populations: the cortex and the pre-granulosa cells of the medulla. TGIF1 expression is associated with an ovarian phenotype in estrogen-mediated sex reversal experiments. Targeted misexpression and gene knockdown indicate that TGIF1 is required, but not sufficient, for proper ovarian cortex formation. In addition, TGIF1 is identified as the first known regulator of juxtacortical medulla development. These findings provide new insights into chicken ovarian differentiation and development, specifically cortical and juxtacortical medulla formation.


Assuntos
Galinhas/genética , Genes Homeobox , Proteínas de Homeodomínio/genética , Ovário/embriologia , Proteínas Repressoras/genética , Animais , Diferenciação Celular , Linhagem da Célula/genética , Embrião de Galinha , Embrião de Mamíferos/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Gônadas/metabolismo , Proteínas de Homeodomínio/metabolismo , Masculino , Ovário/citologia , Ovário/metabolismo , Proteínas Repressoras/metabolismo , Células de Sertoli/metabolismo , Processos de Determinação Sexual/genética , Diferenciação Sexual/genética , Testículo/metabolismo
2.
Malar J ; 19(1): 310, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859210

RESUMO

BACKGROUND: Long-lasting insecticidal nets (LLINs) are the primary malaria prevention and control intervention in many parts of sub-Saharan Africa. While LLINs are expected to last at least 3 years under normal use conditions, they can lose effectiveness because they fall out of use, are discarded, repurposed, physically damaged, or lose insecticidal activity. The contributions of these different interrelated factors to durability of nets and their protection against malaria have been unclear. METHODS: Starting in 2009, LLIN durability studies were conducted in seven countries in Africa over 5 years. WHO-recommended measures of attrition, LLIN use, insecticidal activity, and physical integrity were recorded for eight different net brands. These data were combined with analyses of experimental hut data on feeding inhibition and killing effects of LLINs on both susceptible and pyrethroid resistant malaria vectors to estimate the protection against malaria transmission-in terms of vectorial capacity (VC)-provided by each net cohort over time. Impact on VC was then compared in hypothetical scenarios where one durability outcome measure was set at the best possible level while keeping the others at the observed levels. RESULTS: There was more variability in decay of protection over time by country than by net brand for three measures of durability (ratios of variance components 4.6, 4.4, and 1.8 times for LLIN survival, use, and integrity, respectively). In some countries, LLIN attrition was slow, but use declined rapidly. Non-use of LLINs generally had more effect on LLIN impact on VC than did attrition, hole formation, or insecticide loss. CONCLUSIONS: There is much more variation in LLIN durability among countries than among net brands. Low levels of use may have a larger impact on effectiveness than does variation in attrition or LLIN degradation. The estimated entomological effects of chemical decay are relatively small, with physical decay probably more important as a driver of attrition and non-use than as a direct cause of loss of effect. Efforts to maximize LLIN impact in operational settings should focus on increasing LLIN usage, including through improvements in LLIN physical integrity. Further research is needed to understand household decisions related to LLIN use, including the influence of net durability and the presence of other nets in the household.


Assuntos
Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Inseticidas , Malária/prevenção & controle , Controle de Mosquitos/estatística & dados numéricos , Mosquitos Vetores , Angola , Benin , Gâmbia , Quênia , Malária/transmissão , Malaui , Modelos Teóricos , Moçambique , Senegal
3.
J Infect Dis ; 216(suppl_1): S343-S350, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28838184

RESUMO

The legacy of polio in Africa goes far beyond the tragedies of millions of children with permanent paralysis. It has a positive side, which includes the many well-trained polio staff who have vaccinated children, conducted surveillance, tested stool specimens in the laboratories, engaged with communities, and taken care of polio patients. This legacy also includes support for routine immunization services and vaccine introductions and campaigns for other diseases. As polio funding declines, it is time to take stock of the resources made available with polio funding in Africa and begin to find ways to keep some of the talented staff, infrastructure, and systems in place to work on new public health challenges. The partnerships that helped support polio eradication will need to consider funding to maintain and to strengthen routine immunization services and other maternal, neonatal, and child health programs in Africa that have benefitted from the polio eradication infrastructure.


Assuntos
Erradicação de Doenças , Poliomielite , Saúde Pública , África , Erradicação de Doenças/economia , Erradicação de Doenças/organização & administração , Humanos , Poliomielite/economia , Poliomielite/prevenção & controle , Vigilância em Saúde Pública
4.
Emerg Infect Dis ; 23(9): 1471-1477, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28820129

RESUMO

In September 2011, a total of 511 human cases of anthrax (Bacillus anthracis) infection and 5 deaths were reported in a game management area in the district of Chama, Zambia, near where 85 hippopotamuses (Hippopotamus amphibious) had recently died of suspected anthrax. The human infections generally responded to antibiotics. To clarify transmission, we conducted a cross-sectional, interviewer-administered household survey in villages where human anthrax cases and hippopotamuses deaths were reported. Among 284 respondents, 84% ate hippopotamus meat before the outbreak. Eating, carrying, and preparing meat were associated with anthrax infection. Despite the risk, 23% of respondents reported they would eat meat from hippopotamuses found dead again because of food shortage (73%), lack of meat (12%), hunger (7%), and protein shortage (5%). Chronic food insecurity can lead to consumption of unsafe foods, leaving communities susceptible to zoonotic infection. Interagency cooperation is necessary to prevent outbreaks by addressing the root cause of exposure, such as food insecurity.


Assuntos
Antraz/epidemiologia , Bacillus anthracis/isolamento & purificação , Surtos de Doenças , Abastecimento de Alimentos/economia , Carne/virologia , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Animais , Antraz/tratamento farmacológico , Antraz/mortalidade , Antraz/transmissão , Antibacterianos/uso terapêutico , Artiodáctilos/virologia , Bacillus anthracis/patogenicidade , Estudos Transversais , Características da Família , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , População Rural , Inquéritos e Questionários , Análise de Sobrevida , Zâmbia/epidemiologia , Zoonoses/transmissão , Zoonoses/virologia
5.
Emerg Infect Dis ; 23(13)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29155656

RESUMO

To achieve compliance with the revised World Health Organization International Health Regulations (IHR 2005), countries must be able to rapidly prevent, detect, and respond to public health threats. Most nations, however, remain unprepared to manage and control complex health emergencies, whether due to natural disasters, emerging infectious disease outbreaks, or the inadvertent or intentional release of highly pathogenic organisms. The US Centers for Disease Control and Prevention (CDC) works with countries and partners to build and strengthen global health security preparedness so they can quickly respond to public health crises. This report highlights selected CDC global health protection platform accomplishments that help mitigate global health threats and build core, cross-cutting capacity to identify and contain disease outbreaks at their source. CDC contributions support country efforts to achieve IHR 2005 compliance, contribute to the international framework for countering infectious disease crises, and enhance health security for Americans and populations around the world.


Assuntos
Centers for Disease Control and Prevention, U.S. , Saúde Global , Vigilância em Saúde Pública , Saúde Pública , Fortalecimento Institucional , Controle de Doenças Transmissíveis , Doenças Transmissíveis/epidemiologia , Surtos de Doenças , Emergências , Epidemiologia/educação , Humanos , Cooperação Internacional , Saúde Pública/educação , Saúde Pública/métodos , Administração em Saúde Pública , Estados Unidos , Recursos Humanos , Organização Mundial da Saúde
6.
Emerg Infect Dis ; 22(5): 773-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27089119

RESUMO

Arthropod vectors transmit organisms that cause many emerging and reemerging diseases, and their control is reliant mainly on the use of chemical insecticides. Only a few classes of insecticides are available for public health use, and the increased spread of insecticide resistance is a major threat to sustainable disease control. The primary strategy for mitigating the detrimental effects of insecticide resistance is the development of an insecticide resistance management plan. However, few examples exist to show how to implement such plans programmatically. We describe the formulation and implementation of a resistance management plan for mosquito vectors of human disease in Zambia. We also discuss challenges, steps taken to address the challenges, and directions for the future.


Assuntos
Implementação de Plano de Saúde , Planejamento em Saúde , Resistência a Inseticidas , Animais , Bases de Dados Factuais , Implementação de Plano de Saúde/legislação & jurisprudência , Implementação de Plano de Saúde/métodos , Implementação de Plano de Saúde/organização & administração , Planejamento em Saúde/legislação & jurisprudência , Planejamento em Saúde/organização & administração , Humanos , Controle de Insetos , Insetos Vetores , Malária/prevenção & controle , Malária/transmissão , Vigilância em Saúde Pública , Zâmbia
7.
Malar J ; 15: 106, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26891696

RESUMO

BACKGROUND: A key goal of malaria control is to achieve universal access to, and use of, long-lasting insecticidal nets (LLINs) among people at risk for malaria. Quantifying the number of LLINs needed to achieve and maintain universal coverage requires knowing when nets need replacement. Longitudinal studies have observed physical deterioration in LLINs well before the assumed net lifespan of 3 years. The objective of this study was to describe attrition, physical integrity and insecticide persistence of LLINs over time to assist with better quantification of nets needing replacement. METHODS: 999 LLINs distributed in 2011 in two highly endemic provinces in Zambia were randomly selected, and were enrolled at 12 months old. LLINs were followed every 6 months up to 30 months of age. Holes were counted and measured (finger, fist, and head method) and a proportional hole index (pHI) was calculated. Households were surveyed about net care and repair and if applicable, reasons for attrition. Functional survival was defined as nets with a pHI <643 and present for follow-up. At 12 and 24 months of age, 74 LLINs were randomly selected for examination of insecticidal activity and content using bioassay and chemical analysis methods previously described by the World Health Organization (WHO). RESULTS: A total of 999 LLINs were enrolled; 505 deltamethrin-treated polyester nets and 494 permethrin-treated polyethylene nets. With 74 used to examine insecticide activity, 925 were available for full follow-up. At 30 months, 325 (33 %) LLINs remained. Net attrition was primarily due to disposal (29 %). Presence of repairs and use over a reed mat were significantly associated with larger pHIs. By 30 months, only 56 % of remaining nets met criteria for functional survival. A shorter functional survival was associated with having been washed. At 24 months, nets had reduced insecticidal activity (57 % met WHO minimal criteria) and content (5 % met WHO target insecticide content). CONCLUSIONS: The median functional survival time for LLINs observed the study was 2.5-3 years and insecticide activity and content were markedly decreased by 2 years. A better measure of net survival incorporating insecticidal field effectiveness, net physical integrity, and attrition is needed.


Assuntos
Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Mosquiteiros Tratados com Inseticida/normas , Inseticidas/análise , Humanos , Estudos Longitudinais , Malária/prevenção & controle , Fatores de Tempo , Zâmbia
8.
MMWR Morb Mortal Wkly Rep ; 64(19): 527-31, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25996095

RESUMO

In 1988, the World Health Assembly of the World Health Organization (WHO) resolved to eradicate polio worldwide. Wild poliovirus (WPV) transmission has been interrupted in all but three countries (Afghanistan, Nigeria, and Pakistan). No WPV type 2 cases have been detected worldwide since 1999, and the last WPV type 3 case was detected in Nigeria in November 2012; since 2012, only WPV type 1 has been detected. Circulating vaccine-derived poliovirus (cVDPV), usually type 2, continues to cause cases of paralytic polio in communities with low population immunity. In 2012, the World Health Assembly declared global polio eradication "a programmatic emergency for global public health", and in 2014, WHO declared the international spread of WPV to previously polio-free countries to be "a public health emergency of international concern". This report summarizes global progress toward polio eradication during 2014-2015 and updates previous reports. In 2014, a total of 359 WPV cases were reported in nine countries worldwide. Although reported WPV cases increased in Pakistan and Afghanistan, cases in Nigeria decreased substantially in 2014, and encouraging progress toward global WPV transmission interruption has occurred. Overcoming ongoing challenges to interruption of WPV transmission globally will require sustained programmatic enhancements, including improving the quality of supplementary immunization activities (SIAs) to interrupt transmission in Afghanistan and Pakistan and to prevent WPV exportation to polio-free countries.


Assuntos
Erradicação de Doenças , Saúde Global/estatística & dados numéricos , Poliomielite/prevenção & controle , Vigilância da População , Surtos de Doenças/estatística & dados numéricos , Doenças Endêmicas/estatística & dados numéricos , Humanos , Programas de Imunização , Poliomielite/epidemiologia , Vacinas contra Poliovirus/administração & dosagem
9.
Malar J ; 14: 239, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26054336

RESUMO

BACKGROUND: Long-lasting insecticidal nets (LLINs) are a mainstay of malaria prevention in Africa. More LLINs are available now than in any time previously due to increases in funding for malaria control. LLINs are expected to last three to five years before they need to be replaced. Reports of nets lasting less than three years are frequent in Zambia, which, if true, will increase the number of LLINs needed to maintain universal coverage. METHODS: This study collected nets distributed during mass distribution campaigns. One net was collected from each participating home in 12 districts in 2010 and all nets were examined for holes. One household member was surveyed about net use and care. RESULTS: The study collected 713 polyester nets with a median age of 31 months (range 27-44 months, interquartile (IQR) range: 29-36 months), median number of holes was 17 (IQR: 5-33), and median total hole size was 88.3 sq cm (IQR: 14.5-360.4). The median total number of holes did differ by age of the net, from 27-44 months, but not in a linear fashion. The difference in the number of holes in the newest and oldest nets was not statistically significant. The mean deltamethrin level for all nets was 23 mg/sq m (≥8 mg/sq m is considered effective). There was a larger total hole area in the lower half of the nets (repeat measures ANOVA, F=228.43, df=2, p<0.0001) compared to the upper half and roof of the net. Only 8.7% of nets had evidence of repairs. CONCLUSIONS: At 27-30 months, LLINs already had a large total hole surface area that was equivalent to the oldest nets observed. Nets were often tucked under reed mats which may explain the finding that the largest hole area was found in the lower half of the net. Studies need to be conducted prospectively to determine when physical deterioration occurs and why nets are discarded. Re-enforcing the lower half of the sides of LLINs may help decrease holes.


Assuntos
Mosquiteiros Tratados com Inseticida/normas , Inseticidas/análise , Malária/prevenção & controle , Controle de Mosquitos , Animais , Estudos Transversais , Humanos , Nitrilas/análise , Piretrinas/análise , Zâmbia
10.
Malar J ; 14: 69, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25890159

RESUMO

BACKGROUND: Intermittent preventive treatment of malaria in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) decreases placental parasitaemia, thus improving birth outcomes. Zambian policy recommends monthly SP-IPTp doses given presumptively during pregnancy at each antenatal examination, spaced one month apart after 16 weeks of gestation. The effectiveness of SP-IPTp was evaluated in Zambia where a recent study showed moderate prevalence of Plasmodium falciparum parasites with genetic mutations that confer SP resistance. METHODS: HIV-negative women were enrolled at the time of delivery at two facilities in Mansa, Zambia, an area of high malaria transmission. Women were interviewed and SP exposure was determined by antenatal card documentation or self-reports. Using Poisson regression modelling, the effectiveness of SP-IPTp was evaluated for outcomes of parasitaemia (microscopic examination of maternal peripheral, cord, and placental blood films), maternal anaemia (Hb < 11 g/dl), placental infection (histopathology), and infant outcomes (low birth weight (LBW), preterm delivery, and small for gestational age) in women who took 0-4 doses of SP-IPTp. RESULTS: Participants included 435 women, with a median age of 23 years (range 16-44). Thirty-four women took zero doses of SP-IPTp, while 115, 142 and 144 women took one, two, or ≥ three doses, respectively. Multivariate Poisson regression models considering age, mosquito net usage, indoor residual spraying, urban home, gravidity, facility, wet season delivery, and marital status showed that among paucigravid women ≥ two doses of SP-ITPp compared to one or less doses was associated with a protective effect on LBW (prevalence ratio (PR) 0.33, 95% confidence interval (CI) 0.12-0.91) and any infection (PR 0.76, CI 0.58-0.99). Multivariate models considering SP-IPTp as a continuous variable showed a protective dose-response association with LBW (paucigravid women: PR 0.54, CI 0.33-0.90, multigravid women: PR 0.63, CI 0.41-0.97). CONCLUSIONS: In Mansa, Zambia, an area of moderate SP resistance, ≥ two doses of SP-IPTp were associated with a protective effect from malaria in pregnancy, especially among paucigravid women. Each dose of SP-IPTp contributed to a 46 and 37% decrease in the frequency of LBW among paucigravid and multigravid women, respectively. SP-IPTp remains a viable strategy in this context.


Assuntos
Antimaláricos/uso terapêutico , Malária Falciparum/prevenção & controle , Complicações Parasitárias na Gravidez/prevenção & controle , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Adolescente , Adulto , Estudos de Coortes , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Feminino , Humanos , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Análise Multivariada , Distribuição de Poisson , Gravidez , Prevalência , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem , Zâmbia/epidemiologia
11.
Malar J ; 14: 465, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26586264

RESUMO

BACKGROUND: Repeat national household surveys suggest highly variable malaria transmission and increasing coverage of high-impact malaria interventions throughout Zambia. Many areas of very low malaria transmission, especially across southern and central regions, are driving efforts towards sub-national elimination. CASE DESCRIPTION: Reactive case detection (RCD) is conducted in Southern Province and urban areas of Lusaka in connection with confirmed incident malaria cases presenting to a community health worker (CHW) or clinic and suspected of being the result of local transmission. CHWs travel to the household of the incident malaria case and screen individuals living in adjacent houses in urban Lusaka and within 140 m in Southern Province for malaria infection using a rapid diagnostic test, treating those testing positive with artemether-lumefantrine. DISCUSSION: Reactive case detection improves access to health care and increases the capacity for the health system to identify malaria infections. The system is useful for targeting malaria interventions, and was instrumental for guiding focal indoor residual spraying in Lusaka during the 2014/2015 spray season. Variations to maximize impact of the current RCD protocol are being considered, including the use of anti-malarials with a longer lasting, post-treatment prophylaxis. CONCLUSION: The RCD system in Zambia is one example of a malaria elimination surveillance system which has increased access to health care within rural communities while leveraging community members to build malaria surveillance capacity.


Assuntos
Monitoramento Epidemiológico , Malária/epidemiologia , Combinação Arteméter e Lumefantrina , Artemisininas/administração & dosagem , Cromatografia de Afinidade , Agentes Comunitários de Saúde , Transmissão de Doença Infecciosa , Combinação de Medicamentos , Etanolaminas/administração & dosagem , Fluorenos/administração & dosagem , Acessibilidade aos Serviços de Saúde , Humanos , Incidência , Malária/diagnóstico , Malária/tratamento farmacológico , Malária/transmissão , Zâmbia/epidemiologia
12.
Malar J ; 14: 222, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26017275

RESUMO

BACKGROUND: Accurate and timely malaria data are crucial to monitor the progress towards and attainment of elimination. Lusaka, the capital city of Zambia, has reported very low malaria prevalence in Malaria Indicator Surveys. Issues of low malaria testing rates, high numbers of unconfirmed malaria cases and over consumption of anti-malarials were common at clinics within Lusaka, however. The Government of Zambia (GRZ) and its partners sought to address these issues through an enhanced surveillance and feedback programme at clinic level. METHODS: The enhanced malaria surveillance programme began in 2011 to verify trends in reported malaria, as well as to implement a data feedback loop to improve data uptake, use, and quality. A process of monthly data collection and provision of feedback was implemented within all GRZ health clinics in Lusaka District. During clinic visits, clinic registers were accessed to record the number of reported malaria cases, malaria test positivity rate, malaria testing rate, and proportion of total suspected malaria that was confirmed with a diagnostic test. RESULTS AND DISCUSSION: Following the enhanced surveillance programme, the odds of receiving a diagnostic test for a suspected malaria case increased (OR = 1.54, 95 % CI = 0.96-2.49) followed by an upward monthly trend (OR = 1.05, 95 % CI = 1.01-1.09). The odds of a reported malaria case being diagnostically confirmed also increased monthly (1.09, 95 % CI 1.04-1.15). After an initial 140 % increase (95 % CI = 91-183 %), costs fell by 11 % each month (95 % CI = 5.7-10.9 %). Although the mean testing rate increased from 18.9 to 64.4 % over the time period, the proportion of reported malaria unconfirmed by diagnostic remained high at 76 %. CONCLUSIONS: Enhanced surveillance and implementation of a data feedback loop have substantially increased malaria testing rates and decreased the number of unconfirmed malaria cases and courses of ACT consumed in Lusaka District within just two years. Continued support of enhanced surveillance in Lusaka as well as national scale-up of the system is recommended to reinforce good case management and to ensure timely, reliable data are available to guide targeting of limited malaria prevention and control resources in Zambia.


Assuntos
Monitoramento Epidemiológico , Malária/epidemiologia , Vigilância em Saúde Pública/métodos , Pré-Escolar , Testes Diagnósticos de Rotina/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Malária/diagnóstico , Malária/parasitologia , Prevalência , Zâmbia/epidemiologia
13.
J Infect Dis ; 210 Suppl 1: S74-84, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24154734

RESUMO

BACKGROUND: In response to the 2011 and 2012 polio epidemic in Chad, Chad's Ministry of Public Health, with support from Global Polio Eradication Initiative partners, took steps to increase vaccination coverage of nomadic children with targeted polio campaigns. This article describes the strategies we used to vaccinate nomads in 3 districts of Chad. METHODS: Our targeted interventions involved using mobile vaccination teams, recruiting local nomads to identify settlements, using social mobilization, and offering vaccinations to children, women, and animals. RESULTS: Vaccination coverage of nomadic children 0-59 months of age increased, particularly among those never before vaccinated against polio. These increases occurred mostly in the intervention districts of Dourbali, from 2956 to 8164 vaccinated children, and Kyabe, from 7319 to 15 868. The number of first-time vaccinated nomadic children also increased the most in these districts, from 60 to 131 in Dourbali and from 1302 to 2973 in Kyabe. Coverage in the Massaguet district was only 37.7%. CONCLUSIONS: Our success was probably due to (1) appointment of staff to oversee implementation, (2) engagement of the national government and its partners, (3) participation of nomadic community leaders, (4) intersectoral collaboration between human and animal health services, and (5) flexibility and capacity of vaccinators to vaccinate when and where nomads were available.


Assuntos
Surtos de Doenças , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Vacinas contra Poliovirus/administração & dosagem , Migrantes , Adulto , Animais , Chade/epidemiologia , Criança , Pré-Escolar , Controle de Doenças Transmissíveis/organização & administração , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez
14.
N Engl J Med ; 364(21): 2016-25, 2011 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-21612470

RESUMO

BACKGROUND: The rate of bacterial meningitis declined by 55% in the United States in the early 1990s, when the Haemophilus influenzae type b (Hib) conjugate vaccine for infants was introduced. More recent prevention measures such as the pneumococcal conjugate vaccine and universal screening of pregnant women for group B streptococcus (GBS) have further changed the epidemiology of bacterial meningitis. METHODS: We analyzed data on cases of bacterial meningitis reported among residents in eight surveillance areas of the Emerging Infections Programs Network, consisting of approximately 17.4 million persons, during 1998-2007. We defined bacterial meningitis as the presence of H. influenzae, Streptococcus pneumoniae, GBS, Listeria monocytogenes, or Neisseria meningitidis in cerebrospinal fluid or other normally sterile site in association with a clinical diagnosis of meningitis. RESULTS: We identified 3188 patients with bacterial meningitis; of 3155 patients for whom outcome data were available, 466 (14.8%) died. The incidence of meningitis changed by -31% (95% confidence interval [CI], -33 to -29) during the surveillance period, from 2.00 cases per 100,000 population (95% CI, 1.85 to 2.15) in 1998-1999 to 1.38 cases per 100,000 population (95% CI 1.27 to 1.50) in 2006-2007. The median age of patients increased from 30.3 years in 1998-1999 to 41.9 years in 2006-2007 (P<0.001 by the Wilcoxon rank-sum test). The case fatality rate did not change significantly: it was 15.7% in 1998-1999 and 14.3% in 2006-2007 (P=0.50). Of the 1670 cases reported during 2003-2007, S. pneumoniae was the predominant infective species (58.0%), followed by GBS (18.1%), N. meningitidis (13.9%), H. influenzae (6.7%), and L. monocytogenes (3.4%). An estimated 4100 cases and 500 deaths from bacterial meningitis occurred annually in the United States during 2003-2007. CONCLUSIONS: The rates of bacterial meningitis have decreased since 1998, but the disease still often results in death. With the success of pneumococcal and Hib conjugate vaccines in reducing the risk of meningitis among young children, the burden of bacterial meningitis is now borne more by older adults. (Funded by the Emerging Infections Programs, Centers for Disease Control and Prevention.).


Assuntos
Meningites Bacterianas/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , População Negra/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Haemophilus influenzae , Humanos , Incidência , Lactente , Recém-Nascido , Listeria monocytogenes , Masculino , Meningites Bacterianas/etnologia , Meningites Bacterianas/microbiologia , Pessoa de Meia-Idade , Neisseria meningitidis , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Streptococcus pneumoniae , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricos , Adulto Jovem
15.
Malar J ; 13: 383, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25261276

RESUMO

BACKGROUND: Blood transfusions can reduce mortality among children with severe malarial anaemia, but there is limited evidence quantifying the relationship between paediatric malaria and blood transfusions. This study explores the extent to which the use of paediatric blood transfusions is affected by the number of paediatric malaria visits and admissions. It assesses whether the scale-up of malaria control interventions in a facility catchment area explains the use of paediatric blood transfusions. METHODS: The study was conducted at a referral hospital for 13 rural health centres in rural Zambia. Data were used from facility and patient records covering all paediatric malaria admissions from 2000 to 2008. An interrupted time series analysis using an autoregression-moving-average model was conducted to assess the relationship between paediatric malaria outpatient visits and admissions and the use of paediatric blood transfusions. Further investigation explored whether the use of paediatric blood transfusions over time was consistent with the roll out of malaria control interventions in the hospital catchment area. RESULTS: For each additional paediatric malaria outpatient visit, there were 0.07 additional paediatric blood transfusions (95% CI 0.01-0.13; p < 0.05). For each additional paediatric admission for severe malarial anaemia, there were 1.09 additional paediatric blood transfusions (95% CI 0.95-1.23; p < 0.01). There were 19.1 fewer paediatric blood transfusions per month during the 2004-2006 malaria control period (95% CI 12.1-26.0; p < 0.01), a 50% reduction compared to the preceding period when malaria control was relatively limited. During the 2007-2008 malaria control period, there were 27.5 fewer paediatric blood transfusions per month (95% CI 14.6-40.3; p < 0.01), representing a 72% decline compared to the period with limited malaria control. CONCLUSIONS: Paediatric admissions for severe malarial anaemia largely explain total use of paediatric blood transfusions. The reduction in paediatric blood transfusions is consistent with the timing of the malaria control interventions. Malaria control seems to influence the use of paediatric blood transfusions by reducing the number of paediatric admissions for severe malarial anaemia. Reduced use of blood transfusions could benefit other areas of the health system through greater blood availability, particularly where supply is limited.


Assuntos
Transfusão de Sangue/estatística & dados numéricos , Malária/epidemiologia , Malária/prevenção & controle , Anemia/parasitologia , Anemia/terapia , Transfusão de Sangue/tendências , Pré-Escolar , Hospitalização/estatística & dados numéricos , Hospitalização/tendências , Humanos , Lactente , Recém-Nascido , Análise de Séries Temporais Interrompida , Malária/sangue , Malária/parasitologia , Zâmbia/epidemiologia
16.
Malar J ; 13: 227, 2014 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-24909578

RESUMO

BACKGROUND: Intermittent preventive treatment of malaria in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) decreases adverse effects of malaria during pregnancy. Zambia implemented its IPTp-SP programme in 2003. Emergence of SP-resistant Plasmodium falciparum threatens this strategy. The quintuple mutant haplotype (substitutions in N51I, C59R, S108N in dhfr and A437G and K540E in dhps genes), is associated with SP treatment failure in non-pregnant patients with malaria. This study examined efficacy of IPTp-SP and presence of the quintuple mutant among pregnant women in Mansa, Zambia. METHODS: In Mansa, an area with high malaria transmission, HIV-negative pregnant women presenting to two antenatal clinics for the 1st dose of IPTp-SP with asymptomatic parasitaemia were enrolled and microscopy for parasitaemia was done weekly for five weeks. Outcomes were parasitological failure and adequate parasitological response (no parasitaemia during follow-up). Polymerase chain reaction assays were employed to distinguish recrudescence from reinfection, and identify molecular markers of SP resistance. Survival analysis included those who had reinfection and incomplete follow-up (missed at least one follow-up). RESULTS: Of the 109 women included in the study, 58 (53%) completed all follow-up, 34 (31%) had incomplete follow-up, and 17 (16%) were lost to follow-up after day 0. Of those who had complete follow-up, 15 (26%, 95% confidence interval [CI] [16-38]) had parasitological failure. For the 92 women included in the survival analysis, median age was 20 years (interquartile range [IQR] 18-22), median gestational age was 22 weeks (IQR range 20-24), and 57% were primigravid. There was no difference in time to failure in primigravid versus multigravid women. Of the 84 women with complete haplotype data for the aforementioned loci of the dhfr and dhps genes, 53 (63%, 95% CI [50-70]) had quintuple mutants (two with an additional mutation in A581G of dhps). Among women with complete follow-up and quintuple mutants, 22% had parasitological failure versus 0% without (p = 0.44). CONCLUSIONS: While underpowered, this study found 26% failure rates of SP given the moderate prevalence of the quintuple mutant haplotype. Despite the presence of resistance, SP retained some efficacy in clearing parasites in pregnant women, and may remain a viable option for IPTp in Zambia.


Assuntos
Antimaláricos/uso terapêutico , Malária Falciparum/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Adolescente , Adulto , Animais , Combinação de Medicamentos , Resistência a Medicamentos , Quimioterapia Combinada/métodos , Feminino , Humanos , Mutação , Plasmodium falciparum/efeitos dos fármacos , Gravidez , Análise de Sobrevida , Falha de Tratamento , Adulto Jovem , Zâmbia
17.
Am J Public Health ; 103(4): 755-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23237164

RESUMO

OBJECTIVES: We assessed telephone surveys as a novel surveillance method, comparing data obtained by telephone with existing national influenza surveillance systems, and evaluated the utility of telephone surveys. METHODS: We used the 2007 Behavioral Risk Factor Surveillance System (BRFSS) and the 2007 National Immunization Survey-Adult (NIS-Adult) to estimate the incidence of influenza-like illness (ILI), medically attended ILI, provider-diagnosed influenza, influenza testing, and treatment of influenza with antiviral medications during the 2006-2007 influenza season. RESULTS: With the January-May BRFSS, among persons aged 18 years and older, the cumulative incidence of seasonal ILI and provider-diagnosed influenza was 37.9 and 5.7 adults per 100 persons, respectively. Monthly medically attended ILI and provider-diagnosed influenza among adults were temporally associated with influenza activity, as documented by national surveillance. With the NIS-Adult survey data, estimated provider-diagnosed influenza, influenza testing, and antiviral treatment were 2.8%, 1.4%, and 0.6%, respectively. CONCLUSIONS: Our telephone interview-based estimates of influenza morbidity were consistent with those from national influenza surveillance systems. Telephone surveys may provide an alternative method by which population-based influenza morbidity information can be gathered.


Assuntos
Influenza Humana/epidemiologia , Telefone , Adolescente , Adulto , Idoso , Distribuição de Qui-Quadrado , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Vigilância da População , Fatores de Risco , Estações do Ano , Estados Unidos/epidemiologia
18.
Pan Afr Med J ; 45: 190, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020355

RESUMO

Introduction: the number of wild poliomyelitis cases, worldwide, dropped from 350,000 cases in 1988 to 33 in 2018. Acute flaccid paralysis (AFP) surveillance is a key strategy toward achieving global polio eradication. The 2014 Ebola virus disease (EVD) epidemic in West Africa infected over 28,000 people and had devastating effects on health systems in Guinea, Liberia, and Sierra Leone. We sought to assess the effects of the 2014 Ebola outbreak on AFP surveillance in Guinea and Liberia. Methods: a retrospective cross-sectional analysis was performed for Guinea and Liberia to evaluate EVD´s impact on World Health Organization (WHO) AFP surveillance performance indicators during 2012-2015. Results: both Guinea and Liberia met the WHO target non-polio AFP incidence rate nationally, and generally sub-nationally, prior to the EVD outbreak; rates decreased substantially during the outbreak in seven of eight regions in Guinea and 11 of 15 counties in Liberia. Throughout the study period, both Guinea and Liberia attained appropriate overall targets nationally for "notification" and "stool adequacy" indicators, but each country experienced periods of poor regional/county-specific indicator performance. Conclusion: these findings mirrored the negative effect of the Ebola outbreak on polio elimination activities in both countries and highlights the need to reinforce this surveillance system during times of crisis.


Assuntos
Doença pelo Vírus Ebola , Poliomielite , Humanos , Doença pelo Vírus Ebola/epidemiologia , Libéria/epidemiologia , Guiné/epidemiologia , Estudos Retrospectivos , Estudos Transversais , alfa-Fetoproteínas , Vigilância da População , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Surtos de Doenças , Paralisia/epidemiologia , Paralisia/etiologia
19.
Sci Rep ; 13(1): 16419, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37775676

RESUMO

Major depressive disorder (MDD) and chronic unpredictable stress (CUS) in animals feature comparable cellular and molecular disturbances that involve neurons and glial cells in gray and white matter (WM) in prefrontal brain areas. These same areas demonstrate disturbed connectivity with other brain regions in MDD and stress-related disorders. Functional connectivity ultimately depends on signal propagation along WM myelinated axons, and thus on the integrity of nodes of Ranvier (NRs) and their environment. Various glia-derived proteoglycans interact with NR axonal proteins to sustain NR function. It is unclear whether NR length and the content of associated proteoglycans is altered in prefrontal cortex (PFC) WM of human subjects with MDD and in experimentally stressed animals. The length of WM NRs in histological sections from the PFC of 10 controls and 10 MDD subjects, and from the PFC of control and CUS rats was measured. In addition, in WM of the same brain region, five proteoglycans, tenascin-R and NR protein neurofascin were immunostained or their levels measured with western blots. Analysis of covariance and t-tests were used for group comparisons. There was dramatic reduction of NR length in PFC WM in both MDD and CUS rats. Proteoglycan BRAL1 immunostaining was reduced at NRs and in overall WM of MDD subjects, as was versican in overall WM. Phosphacan immunostaining and levels were increased in both in MDD and CUS. Neurofascin immunostaining at NRs and in overall WM was significantly increased in MDD. Reduced length of NRs and increased phosphacan and neurocan in MDD and stressed animals suggest that morphological and proteoglycan changes at NRs in depression may be related to stress exposure and contribute to connectivity alterations. However, differences between MDD and CUS for some NR related markers may point to other mechanisms affecting the structure and function of NRs in MDD.


Assuntos
Transtorno Depressivo Maior , Substância Branca , Humanos , Ratos , Animais , Substância Branca/patologia , Nós Neurofibrosos/metabolismo , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/metabolismo , Córtex Pré-Frontal/metabolismo , Versicanas/metabolismo
20.
N Engl J Med ; 360(3): 244-56, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19144940

RESUMO

BACKGROUND: Invasive pneumococcal disease declined among children and adults after the introduction of the pediatric heptavalent pneumococcal conjugate vaccine (PCV7) in 2000, but its effect on pneumococcal meningitis is unclear. METHODS: We examined trends in pneumococcal meningitis from 1998 through 2005 using active, population-based surveillance data from eight sites in the United States. Isolates were grouped into PCV7 serotypes (4, 6B, 9V, 14, 18C, 19F, and 23F), PCV7-related serotypes (6A, 9A, 9L, 9N, 18A, 18B, 18F, 19B, 19C, 23A, and 23B), and non-PCV7 serotypes (all others). Changes in the incidence of pneumococcal meningitis were assessed against baseline values from 1998-1999. RESULTS: We identified 1379 cases of pneumococcal meningitis. The incidence declined from 1.13 cases to 0.79 case per 100,000 persons between 1998-1999 and 2004-2005 (a 30.1% decline, P<0.001). Among persons younger than 2 years of age and those 65 years of age or older, the incidence decreased during the study period by 64.0% and 54.0%, respectively (P<0.001 for both groups). Rates of PCV7-serotype meningitis declined from 0.66 case to 0.18 case (a 73.3% decline, P<0.001) among patients of all ages. Although rates of PCV7-related-serotype disease decreased by 32.1% (P=0.08), rates of non-PCV7-serotype disease increased from 0.32 to 0.51 (an increase of 60.5%, P<0.001). The percentages of cases from non-PCV7 serotypes 19A, 22F, and 35B each increased significantly during the study period. On average, 27.8% of isolates were nonsusceptible to penicillin, but fewer isolates were nonsusceptible to chloramphenicol (5.7%), meropenem (16.6%), and cefotaxime (11.8%). The proportion of penicillin-nonsusceptible isolates decreased between 1998 and 2003 (from 32.0% to 19.4%, P=0.01) but increased between 2003 and 2005 (from 19.4% to 30.1%, P=0.03). CONCLUSIONS: Rates of pneumococcal meningitis have decreased among children and adults since PCV7 was introduced. Although the overall effect of the vaccine remains substantial, a recent increase in meningitis caused by non-PCV7 serotypes, including strains nonsusceptible to antibiotics, is a concern.


Assuntos
Meningite Pneumocócica/prevenção & controle , Vacinas Pneumocócicas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Farmacorresistência Bacteriana , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Incidência , Lactente , Recém-Nascido , Meningite Pneumocócica/epidemiologia , Meningite Pneumocócica/microbiologia , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Sorotipagem , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/efeitos dos fármacos , Estados Unidos/epidemiologia , Vacinas Conjugadas , Adulto Jovem
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