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1.
BMJ ; 372: n334, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597166

RESUMO

OBJECTIVE: To directly measure the fatal impact of coronavirus disease 2019 (covid-19) in an urban African population. DESIGN: Prospective systematic postmortem surveillance study. SETTING: Zambia's largest tertiary care referral hospital. PARTICIPANTS: Deceased people of all ages at the University Teaching Hospital morgue in Lusaka, Zambia, enrolled within 48 hours of death. MAIN OUTCOME MEASURE: Postmortem nasopharyngeal swabs were tested via reverse transcriptase quantitative polymerase chain reaction (PCR) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Deaths were stratified by covis-19 status, location, age, sex, and underlying risk factors. RESULTS: 372 participants were enrolled between June and September 2020; PCR results were available for 364 (97.8%). SARS-CoV-2 was detected in 58/364 (15.9%) according to the recommended cycle threshold value of <40 and in 70/364 (19.2%) when expanded to any level of PCR detection. The median age at death among people with a positive test for SARS-CoV-2 was 48 (interquartile range 36-72) years, and 69% (n=48) were male. Most deaths in people with covid-19 (51/70; 73%) occurred in the community; none had been tested for SARS-CoV-2 before death. Among the 19/70 people who died in hospital, six were tested before death. Among the 52/70 people with data on symptoms, 44/52 had typical symptoms of covid-19 (cough, fever, shortness of breath), of whom only five were tested before death. Covid-19 was identified in seven children, only one of whom had been tested before death. The proportion of deaths with covid-19 increased with age, but 76% (n=53) of people who died were aged under 60 years. The five most common comorbidities among people who died with covid-19 were tuberculosis (22; 31%), hypertension (19; 27%), HIV/AIDS (16; 23%), alcohol misuse (12; 17%), and diabetes (9; 13%). CONCLUSIONS: Contrary to expectations, deaths with covid-19 were common in Lusaka. Most occurred in the community, where testing capacity is lacking. However, few people who died at facilities were tested, despite presenting with typical symptoms of covid-19. Therefore, cases of covid-19 were under-reported because testing was rarely done not because covid-19 was rare. If these data are generalizable, the impact of covid-19 in Africa has been vastly underestimated.


Assuntos
/mortalidade , /isolamento & purificação , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Autopsia , /virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , População Urbana/estatística & dados numéricos , Zâmbia/epidemiologia
2.
Arch Virol ; 166(3): 915-919, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33475831

RESUMO

Tick-borne pathogens are an emerging public health threat worldwide. However, information on tick-borne viruses is scanty in sub-Saharan Africa. Here, by RT-PCR, 363 ticks (Amblyomma, Hyalomma and Rhipicephalus) in the Namwala and Livingstone districts of Zambia were screened for tick-borne phleboviruses (TBPVs). TBPVs (L gene) were detected in 19 (5.2%) Rhipicephalus ticks in Namwala. All the detected TBPVs were Shibuyunji viruses. Phylogenetically, they were closely related to American dog tick phlebovirus. This study highlights the possible role of Rhipicephalus ticks as the main host of Shibuyunji virus and suggests that these viruses may be present outside the area where they were initially discovered.


Assuntos
/virologia , Febre por Flebótomos/epidemiologia , Phlebovirus/isolamento & purificação , Rhipicephalus/virologia , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Variação Genética/genética , Febre por Flebótomos/transmissão , Febre por Flebótomos/virologia , Phlebovirus/genética , Filogenia , Prevalência , Análise de Sequência de DNA , Doenças Transmitidas por Carrapatos/virologia , Zâmbia/epidemiologia
3.
BMC Pregnancy Childbirth ; 21(1): 98, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33516183

RESUMO

BACKGROUND: This study estimated the prevalence of curable sexually transmitted and reproductive tract infections (STIs/RTIs) among pregnant women attending antenatal care (ANC) in rural Zambia, evaluated the effectiveness of syndromic management of STIs/RTIs versus reference-standard laboratory diagnoses, and identified determinants of curable STIs/RTIs during pregnancy. METHODS: A total of 1086 pregnant women were enrolled at ANC booking, socio-demographic information and biological samples were collected, and the provision of syndromic management based care was documented. The Piot-Fransen model was used to evaluate the effectiveness of syndromic management versus etiological testing, and univariate and multivariate logistic regression analyses were used to identify determinants of STIs/RTIs. RESULTS: Participants had a mean age of 25.6 years and a mean gestational age of 22.0 weeks. Of 1084 women, 700 had at least one STI/RTI (64.6%; 95% confidence interval [CI], 61.7, 67.4). Only 10.2% of infected women received any treatment for a curable STI/RTI (excluding syphilis). Treatment was given to 0 of 56 women with chlamydia (prevalence 5.2%; 95% CI, 4.0, 6.6), 14.7% of participants with gonorrhoea (prevalence 3.1%; 95% CI, 2.2, 4.4), 7.8% of trichomoniasis positives (prevalence 24.8%; 95% CI, 22.3, 27.5) and 7.5% of women with bacterial vaginosis (prevalence 48.7%; 95% CI, 45.2, 51.2). An estimated 7.1% (95% CI, 5.6, 8.7) of participants had syphilis and received treatment. Women < 20 years old were more likely (adjusted odds ratio [aOR] = 5.01; 95% CI: 1.23, 19.44) to have gonorrhoea compared to women ≥30. The odds of trichomoniasis infection were highest among primigravidae (aOR = 2.40; 95% CI: 1.69, 3.40), decreasing with each subsequent pregnancy. Women 20 to 29 years old were more likely to be diagnosed with bacterial vaginosis compared to women ≥30 (aOR = 1.58; 95% CI: 1.19, 2.10). Women aged 20 to 29 and ≥ 30 years had higher odds of infection with syphilis, aOR = 3.96; 95% CI: 1.40, 11.20 and aOR = 3.29; 95% CI: 1.11, 9.74 respectively, compared to women under 20. CONCLUSIONS: Curable STIs/RTIs were common and the majority of cases were undetected and untreated. Alternative approaches are urgently needed in the ANC setting in rural Zambia.


Assuntos
Coinfecção/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Infecções do Sistema Genital/epidemiologia , Doenças Sexualmente Transmissíveis/epidemiologia , Adulto , Coinfecção/diagnóstico , Coinfecção/parasitologia , Estudos Transversais , Feminino , Gonorreia/diagnóstico , Gonorreia/epidemiologia , Humanos , Modelos Logísticos , Análise Multivariada , Gravidez , Cuidado Pré-Natal , Prevalência , Infecções do Sistema Genital/diagnóstico , Infecções do Sistema Genital/parasitologia , População Rural , Doenças Sexualmente Transmissíveis/diagnóstico , Doenças Sexualmente Transmissíveis/parasitologia , Fatores Socioeconômicos , Sífilis/epidemiologia , Tricomoníase/epidemiologia , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/parasitologia , Adulto Jovem , Zâmbia/epidemiologia
4.
Infect Dis Poverty ; 10(1): 5, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413680

RESUMO

BACKGROUND: The pandemic of the coronavirus disease 2019 (COVID-19) has caused substantial disruptions to health services in the low and middle-income countries with a high burden of other diseases, such as malaria in sub-Saharan Africa. The aim of this study is to assess the impact of COVID-19 pandemic on malaria transmission potential in malaria-endemic countries in Africa. METHODS: We present a data-driven method to quantify the extent to which the COVID-19 pandemic, as well as various non-pharmaceutical interventions (NPIs), could lead to the change of malaria transmission potential in 2020. First, we adopt a particle Markov Chain Monte Carlo method to estimate epidemiological parameters in each country by fitting the time series of the cumulative number of reported COVID-19 cases. Then, we simulate the epidemic dynamics of COVID-19 under two groups of NPIs: (1) contact restriction and social distancing, and (2) early identification and isolation of cases. Based on the simulated epidemic curves, we quantify the impact of COVID-19 epidemic and NPIs on the distribution of insecticide-treated nets (ITNs). Finally, by treating the total number of ITNs available in each country in 2020, we evaluate the negative effects of COVID-19 pandemic on malaria transmission potential based on the notion of vectorial capacity. RESULTS: We conduct case studies in four malaria-endemic countries, Ethiopia, Nigeria, Tanzania, and Zambia, in Africa. The epidemiological parameters (i.e., the basic reproduction number [Formula: see text] and the duration of infection [Formula: see text]) of COVID-19 in each country are estimated as follows: Ethiopia ([Formula: see text], [Formula: see text]), Nigeria ([Formula: see text], [Formula: see text]), Tanzania ([Formula: see text], [Formula: see text]), and Zambia ([Formula: see text], [Formula: see text]). Based on the estimated epidemiological parameters, the epidemic curves simulated under various NPIs indicated that the earlier the interventions are implemented, the better the epidemic is controlled. Moreover, the effect of combined NPIs is better than contact restriction and social distancing only. By treating the total number of ITNs available in each country in 2020 as a baseline, our results show that even with stringent NPIs, malaria transmission potential will remain higher than expected in the second half of 2020. CONCLUSIONS: By quantifying the impact of various NPI response to the COVID-19 pandemic on malaria transmission potential, this study provides a way to jointly address the syndemic between COVID-19 and malaria in malaria-endemic countries in Africa. The results suggest that the early intervention of COVID-19 can effectively reduce the scale of the epidemic and mitigate its impact on malaria transmission potential.


Assuntos
/epidemiologia , Malária/epidemiologia , Malária/terapia , /transmissão , Etiópia/epidemiologia , Humanos , Malária/transmissão , Cadeias de Markov , Nigéria/epidemiologia , Pandemias , Sindemia , Tanzânia/epidemiologia , Zâmbia/epidemiologia
5.
BMC Infect Dis ; 21(1): 118, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33499820

RESUMO

BACKGROUND: Early infant diagnosis of HIV infection is challenging in sub-Saharan Africa, particularly in rural areas, leading to delays in diagnosis and treatment. Use of a point-of-care test would overcome many challenges. This study evaluated the validity of a novel point-of-care p24 antigen detection test (LYNX) in rural and urban settings in southern Zambia. METHODS: Two studies were conducted: a cross-sectional study from 2014 to 2015 at Macha Hospital (LYNX Hospital study) and a longitudinal study from 2016 to 2018 at 12 health facilities in Southern Province, Zambia (NSEBA study). In both studies, children attending the facilities for early infant diagnosis were enrolled and a blood sample was collected for routine testing at the central lab and immediate on-site testing with the LYNX test. The performance of the LYNX test was measured in comparison to nucleic acid-based testing at the central lab. RESULTS: In the LYNX Hospital study, 210 tests were performed at a median age of 23.5 weeks (IQR: 8.9, 29.0). The sensitivity and specificity of the test were 70.0 and 100.0%, respectively. In the NSEBA study, 2608 tests were performed, including 1305 at birth and 1222 on children ≥4 weeks of age. For samples tested at birth, sensitivity was 13.6% (95% CI: 2.9, 34.9) and specificity was 99.6% (95% CI: 99.1, 99.9). While specificity was high for all ages, sensitivity increased with age and was higher for participants tested at ≥4 weeks of age (80.6%; 95% CI: 67.4, 93.7). Children with positive nucleic acid tests were more likely to be negative by the LYNX test if their mother received antiretroviral therapy during pregnancy (60.7% vs. 24.2%; p = 004). CONCLUSIONS: Considering the high specificity and moderate sensitivity that increased with age, the LYNX test could be of value for early infant diagnosis for infants ≥4 weeks of age, particularly in rural areas where centralized testing leads to long delays. Point-of-care tests with moderate sensitivity and high specificity that are affordable, easy-to-use, and easily implemented and maintained should be developed to expand access to testing and deliver same-day results to infants in areas where it is not feasible to implement nucleic acid-based point-of-care assays.


Assuntos
Proteína do Núcleo p24 do HIV/análise , Infecções por HIV/diagnóstico , Testes Imediatos , Fármacos Anti-HIV/uso terapêutico , Estudos Transversais , Testes Diagnósticos de Rotina , Diagnóstico Precoce , Estudos de Viabilidade , Feminino , Proteína do Núcleo p24 do HIV/sangue , Infecções por HIV/congênito , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Testes Imunológicos , Ciência da Implementação , Lactente , Recém-Nascido , Transmissão Vertical de Doença Infecciosa , Estudos Longitudinais , Masculino , Triagem Neonatal/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , População Rural , Sensibilidade e Especificidade , Zâmbia/epidemiologia
6.
Chemosphere ; 262: 127788, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182082

RESUMO

Lead (Pb) interferes with various bodily functions. Although high blood Pb (Pb-B) levels in residents from Kabwe, Zambia have been reported, the accumulation pattern of other metals remains unknown. The study was designed to determine the Pb-B, blood cadmium (Cd-B), and zinc (Zn-B) values of 504 representative samples from Kabwe, as well as the potential associated adverse health effects. The Pb-B level ranged from 0.79 to 154.75 µg/dL and generally increased in areas near the mine. A significant elevation of Cd-B was observed in two areas (0.37 ± 0.26 and 0.32 ± 0.30 µg/L) where the two highest mean Pb-B levels were recorded. By contrast, the Zn-B values did not differ greatly with respect to area. Some blood biochemical parameters relating to hepatic and renal functions were out of the normal range in approximately 20-50% of studied adult participants. The δ-aminolevulinic acid dehydratase (δ-ALAD) activity was significantly inhibited in the two areas contaminated by Pb and Cd. A significant negative relationship was observed between metal levels and clinical parameters, e.g., between Pb-B and δ-ALAD for all the age categories and between Cd-B and the estimated glomerular filtration rate for all the age categories except 0-4 years. The elevated Cd-B in areas near the mine relative to the other areas suggested the potential adverse health effects of Cd and/or the interaction of Pb and Cd. A significant association of metal levels with clinical parameters also indicated the effects of metal exposure on hematopoietic, hepatic, and renal systems.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/análise , Metais/análise , Adulto , Cádmio/análise , Coleta de Dados , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental/métodos , Taxa de Filtração Glomerular , Humanos , Fígado/química , Registros , Valores de Referência , Adulto Jovem , Zâmbia , Zinco
7.
J Environ Manage ; 279: 111821, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340964

RESUMO

Information plays an important role in technology adoption and behavior change. This may be particularly true for pesticide decisions, which affect farmer income, health, and the environment. Pesticide use is increasing, and farmers often have incomplete knowledge of how pesticides affect crop production and health. Researchers regularly recommend information interventions to improve pesticide knowledge. This study uses a randomized controlled trial of a pesticide training program in Zambia to identify the effects of information on farmer knowledge of both the health risks and the production benefits of pesticides. We use detailed knowledge assessments covering identification and interpretation of toxicity color labels, pest control properties, and exposure to reveal a more complete picture of pesticide knowledge and to identify where information can have the greatest impact. Our results show that training significantly improved farmer knowledge, particularly for the more complicated pesticide characteristics that are harder to learn from experience. We also find that more experienced farmers had worse prior knowledge of pesticide toxicity, though they also had larger increases from training. Overall, our results suggest that pesticide information interventions should focus on the pest control properties of pesticides and on showing pesticides' true colors through toxicity identification by color labels.


Assuntos
Cor , Fazendeiros , Exposição Ocupacional , Praguicidas , Rotulagem de Produtos , Agricultura , Educação , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Exposição Ocupacional/prevenção & controle , Zâmbia
8.
Afr J AIDS Res ; 19(4): 296-303, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33337978

RESUMO

HIV-incidence studies are used to identify at-risk populations for HIV-prevention trials and interventions, but loss to follow-up (LTFU) can bias results if participants who remain differ from those who drop out. We investigated the incidence of and factors associated with LTFU among Zambian female sex workers (FSWs) in an HIV-incidence cohort from 2012 to 2017. Enrolled participants returned at month one, month three and quarterly thereafter. FSWs were considered LTFU if they missed six consecutive months, or if their last visit was six months before the study end date. Of 420 FSWs, 139 (33%) were LTFU at a rate of 15.7 per 100 person years. In multivariable analysis, LTFU was greater for FSWs who never used alcohol, began sex work above the age of consent, and had a lower volume of new clients. Our study appeared to retain FSWs in most need of HIV-prevention services offered at follow-up.


Assuntos
Infecções por HIV/epidemiologia , Perda de Seguimento , Profissionais do Sexo/estatística & dados numéricos , Adolescente , Adulto , Estudos de Coortes , Feminino , Seguimentos , Infecções por HIV/prevenção & controle , Humanos , Incidência , Fatores de Risco , Adulto Jovem , Zâmbia/epidemiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-33334018

RESUMO

BACKGROUND: Thousands of artisanal workers are exposed to mineral dusts from various origins in the African Copperbelt. We determined the prevalence of respiratory symptoms, pulmonary function, and urinary metals among artisanal stone-crushers in Lubumbashi. METHODS: We conducted a cross-sectional study of 48 male artisanal stone-crushers and 50 male taxi-drivers using a standardized questionnaire and spirometry. Concentrations of trace metals were measured by Inductively Coupled - Plasma Mass Spectrometry (ICP-MS) in urine spot samples. RESULTS: Urinary Co, Ni, As, and Se were higher in stone-crushers than in control participants. Wheezing was more prevalent (p = 0.021) among stone-crushers (23%) than among taxi-drivers (6%). In multiple logistic regression analysis, the job of a stone-crusher was associated to wheezing (adjusted Odds Ratio 4.45, 95% Confidence Interval 1.09-18.24). Stone-crushers had higher values (% predicted) than taxi-drivers for Forced Vital Capacity (105.4 ± 15.9 vs. 92.2 ± 17.8, p = 0.048), Forced Expiratory Volume in 1 Second (104.4 ± 13.7 vs. 88.0 ± 19.6, p = 0.052), and Maximum Expiratory Flow at 25% of the Forced Vital Capacity (79.0.1 ± 20.7 vs. 55.7 ± 30.1, p = 0.078). CONCLUSION: Stone-crushers were more heavily exposed to mineral dust and various trace elements than taxi-drivers, and they had a fourfold increased risk of reporting wheezing, but they did not have evidence of more respiratory impairment than taxi-drivers.


Assuntos
Poeira , Exposição Ocupacional , Estudos Transversais , República Democrática do Congo/epidemiologia , Poeira/análise , Humanos , Masculino , Zâmbia
10.
MMWR Morb Mortal Wkly Rep ; 69(42): 1547-1548, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33090982

RESUMO

Zambia is a landlocked, lower-middle income country in southern Africa, with a population of 17 million (1). The first known cases of coronavirus disease 2019 (COVID-19) in Zambia occurred in a married couple who had traveled to France and were subject to port-of-entry surveillance and subsequent remote monitoring of travelers with a history of international travel for 14 days after arrival. They were identified as having suspected cases on March 18, 2020, and tested for COVID-19 after developing respiratory symptoms during the 14-day monitoring period. In March 2020, the Zambia National Public Health Institute (ZNPHI) defined a suspected case of COVID-19 as 1) an acute respiratory illness in a person with a history of international travel during the 14 days preceding symptom onset; or 2) acute respiratory illness in a person with a history of contact with a person with laboratory-confirmed COVID-19 in the 14 days preceding symptom onset; or 3) severe acute respiratory illness requiring hospitalization; or 4) being a household or close contact of a patient with laboratory-confirmed COVID-19. This definition was adapted from World Health Organization (WHO) interim guidance issued March 20, 2020, on global surveillance for COVID-19 (2) to also include asymptomatic contacts of persons with confirmed COVID-19. Persons with suspected COVID-19 were identified through various mechanisms, including port-of-entry surveillance, contact tracing, health care worker (HCW) testing, facility-based inpatient screening, community-based screening, and calls from the public into a national hotline administered by the Disaster Management and Mitigation Unit and ZNPHI. Port-of-entry surveillance included an arrival screen consisting of a temperature scan, report of symptoms during the preceding 14 days, and collection of a history of travel and contact with persons with confirmed COVID-19 in the 14 days before arrival in Zambia, followed by daily remote telephone monitoring for 14 days. Travelers were tested for SARS-CoV-2, the virus that causes COVID-19, if they were symptomatic upon arrival or developed symptoms during the 14-day monitoring period. Persons with suspected COVID-19 were tested as soon as possible after evaluation for respiratory symptoms or within 7 days of last known exposure (i.e., travel or contact with a confirmed case). All COVID-19 diagnoses were confirmed using real-time reverse transcription-polymerase chain reaction (RT-PCR) testing (SARS-CoV-2 Nucleic Acid Detection Kit, Maccura) of nasopharyngeal specimens; all patients with confirmed COVID-19 were admitted into institutional isolation at the time of laboratory confirmation, which was generally within 36 hours. COVID-19 patients were deemed recovered and released from isolation after two consecutive PCR-negative test results ≥24 hours apart. A Ministry of Health memorandum was released on April 13, 2020, mandating testing in public facilities of 1) all persons admitted to medical and pediatric wards regardless of symptoms; 2) all patients being admitted to surgical and obstetric wards, regardless of symptoms; 3) any outpatient with fever, cough, or shortness of breath; and 4) any facility or community death in a person with respiratory symptoms, and 5) biweekly screening of all HCWs in isolation centers and health facilities where persons with COVID-19 had been evaluated. This report describes the first 100 COVID-19 cases reported in Zambia, during March 18-April 28, 2020.


Assuntos
Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Vigilância em Saúde Pública , Adulto , Técnicas de Laboratório Clínico , Busca de Comunicante , Feminino , Humanos , Masculino , Pandemias , Doença Relacionada a Viagens , Zâmbia/epidemiologia
13.
Zootaxa ; 4838(1): zootaxa.4838.1.7, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-33056836

RESUMO

Four new Tapinomorphus species are described and illustrated: Tapinomorphus angolanus sp. nov. from Angola, T. kudrnai sp. nov. from Zambia, T. latipennis sp. nov. and T. verunkae sp. nov. from Zimbabwe. This brings the total number of species in the genus to 20. Habitus images and illustrations of important characters are provided.


Assuntos
Besouros , Gorgulhos , Angola , Animais , Zâmbia , Zimbábue
14.
BMC Infect Dis ; 20(1): 760, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33059620

RESUMO

BACKGROUND: A more stringent QuantiFERON-TB Gold In-Tube (QFT) conversion (from negative to positive) definition has been proposed to allow more definite detection of recent tuberculosis (TB) infection. We explored alternative conversion definitions to assist the interpretation of serial QFT results and estimate incidence of TB infection in a large cohort study. METHODS: We used QFT serial results from TB household contacts aged ≥15 years, collected at baseline and during two follow-up visits (2006-2011) as part of a cohort study in 24 communities in Zambia and South Africa (SA). Conversion rates using the manufacturers' definition (interferon-gamma (IFN-g) < 0.35 to ≥0.35, 'def1') were compared with stricter definitions (IFN-g < 0.2 to ≥0.7 IU/ml, 'def2'; IFN-g < 0.2 to ≥1.05 IU/ml, 'def3'; IFN-g < 0.2 to ≥1.4 IU/ml, 'def4'). Poisson regression was used for analysis. RESULTS: One thousand three hundred sixty-five individuals in Zambia and 822 in SA had QFT results available. Among HIV-negative individuals, the QFT conversion rate was 27.4 per 100 person-years (CI:22.9-32.6) using def1, 19.0 using def2 (CI:15.2-23.7), 14.7 using def3 (CI:11.5-18.8), and 12.0 using def4 (CI:9.2-15.7). Relative differences across def1-def4 were similar in Zambia and SA. Using def1, conversion was less likely if HIV positive not on antiretroviral treatment compared to HIV negative (aRR = 0.7, 95%CI = 0.4-0.9), in analysis including both countries. The same direction of associations were found using def 2-4. CONCLUSION: High conversion rates were found even with the strictest definition, indicating high incidence of TB infection among household contacts of TB patients in these communities. The trade-off between sensitivity and specificity using different thresholds of QFT conversion remains unknown due to the absence of a reference standard. However, we identified boundaries within which an appropriate definition might fall, and our strictest definition plausibly has high specificity.


Assuntos
Testes de Liberação de Interferon-gama/métodos , Tuberculose/diagnóstico , Antirretrovirais/uso terapêutico , Estudos de Coortes , Busca de Comunicante , Características da Família , Soropositividade para HIV , Humanos , Incidência , Prevalência , África do Sul/epidemiologia , Tuberculose/epidemiologia , Zâmbia/epidemiologia
15.
S Afr Med J ; 110(9): 858-863, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32880268

RESUMO

As COVID-19 spreads rapidly across Africa, causing havoc to economies and disruption to already fragile healthcare systems, it is becoming clear that despite standardised global health strategies, national and local government responses must be tailored to their individual settings. Some African countries have adopted stringent measures such as national lockdown, quarantine or isolation, in combination with good hand hygiene, mandatory wearing of masks and physical distancing, to prevent an impending healthcare crisis. The impact of stringent measures in low- to middle-income African countries has bought time for healthcare facilities to prepare for the onslaught of COVID-19 cases, but some measures have been challenging to implement. In some settings, public health measures have been associated with serious violations of individual rights owing to abuse of power and gaps in implementation of well-intentioned policy. Collateral damage with regard to non-COVID-19 diseases that were suboptimally managed in pre-pandemic times may mean that lives lost from other diseases could exceed those saved from COVID-19. While individuals complying with lockdown regulations have embraced an acceptance of the concept of the common good, at a broad community level many are finding the transition from individualism to collective thinking required during a pandemic difficult to navigate. In this article, we look at government responses to the pandemic in six African countries (Malawi, South Africa, Uganda, Zambia, Zimbabwe and Botswana), and highlight ethical concerns arising in these contexts.


Assuntos
Direitos Civis/ética , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Autonomia Pessoal , Pneumonia Viral/prevenção & controle , Saúde Pública/ética , África , Betacoronavirus , Botsuana , Direitos Civis/legislação & jurisprudência , Infecções por Coronavirus/epidemiologia , Liberdade , Humanos , Malaui , Pneumonia Viral/epidemiologia , Saúde Pública/legislação & jurisprudência , África do Sul , Uganda , Zâmbia , Zimbábue
16.
PLoS One ; 15(9): e0238748, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970697

RESUMO

Antenatal progesterone prevents preterm birth (PTB) in women with a short cervix or prior PTB in daily vaginal or weekly injectable formulations, respectively. Neither has been tested for the indication of maternal HIV, which is associated with an elevated risk of PTB. The Vaginal Progesterone (VP) Trial was a pilot feasibility study of VP to prevent HIV-related PTB in Lusaka, Zambia. Using mixed methods, we concurrently evaluated the acceptability of the trial and the study product among participants. Over a 1-year period, we enrolled 140 pregnant women living with HIV into a double-masked, placebo-controlled, randomized trial of daily self-administered VP or placebo. We administered an endline questionnaire to all participants and conducted in-depth interviews with 30 participants to assess barriers and facilitators to uptake and retention in the trial and to study product adherence. All interviews were audiotaped, transcribed, translated into English as needed, and independently coded by two analysts to capture emerging themes. Of 131 participants who completed the questionnaire, 128 (98%) reported that nothing was difficult when asked the hardest part about using the study product. When given a hypothetical choice between vaginal and injectable progesterone, 97 (74%) chose vaginal, 31 (24%) injectable, and 3 (2%) stated no preference. Most interviewees reported no difficulties with using the study product; others cited minor side effects and surmountable challenges. Strategies that supported adherence included setting alarms, aligning dosing with antiretrovirals, receiving encouragement from friends and family, sensing a benefit to their unborn baby, and positive feedback from study staff. Participants who reported preference of a vaginal medication over injectable described familiarity with the vaginal product, a fear of needles and resulting pain, and inconvenience of a weekly clinic visit. Those who would prefer weekly injections cited fewer doses to remember. Perceived barriers to study participation included mistrust about the motivations behind research, suspicion of Satanism, and futility or possible harm from a placebo. We report key influences on acceptability of a randomized trial of VP to prevent PTB among HIV-infected women in Zambia, which should inform methods to promote uptake, adherence, and retention in a full-scale trial.


Assuntos
Infecções por HIV/complicações , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Nascimento Prematuro/prevenção & controle , Nascimento Prematuro/virologia , Progesterona/administração & dosagem , Progesterona/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto/psicologia , Administração Intravaginal , Adulto , Feminino , Humanos , Preferência do Paciente , Inquéritos e Questionários , Zâmbia
17.
PLoS One ; 15(9): e0238724, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32956369

RESUMO

Wheat blast caused by Magnaporthe oryzae pathotype Triticum (MoT) is a threat to wheat production especially in the warmer-humid environments. In Zambia, wheat blast symptoms were observed for the first time on wheat (Triticum aestivum L.) grown in experimental plots and five farmers' fields in Mpika district of Muchinga Province during the 2017-18 rainy season. Infected plants showed the typical wheat blast symptoms with the spike becoming partially or completely bleached with the blackening of the rachis in a short span of time. Incidence of blast symptoms on nearly all wheat heads was high and ranged from 50 to 100%. Examination of diseased plant leaves showed the presence of elliptical, grayish to tan necrotic lesions with dark borders on the leaf often mixed with other foliar diseases. A study was conducted to isolate and identify the causal pathogen(s) using classical and molecular methods and determine the pathogenicity of the detected disease causal agent. Morphobiometrical determination of causal pathogen revealed conidia with characteristic pear shaped 2-septate hyaline spores associated with M. oryzae species. Preliminary polymerase chain reaction screening of six isolates obtained from wheat blast infected samples with diagnostic primers (MoT3F/R) was conducted at ZARI, Zambia, and subsequent analysis of two isolates with MoT3F/R and C17F/R was performed at USDA-ARS, USA. Both experiments confirmed that MoT is the causal agent of wheat blast in Zambia. Further, pathogenicity tests performed with pure culture isolates from samples WS4 and WS5 produced typical blast symptoms on all the six inoculated wheat genotypes. Results of this study indicate that MoT is causing wheat blast in rain-fed wheat grown in Zambia, thus making it the first report of MoT in Zambia and Africa. This inter-continental movement of the pathogen (disease) has serious implication for wheat production and trade that needs to be urgently addressed.


Assuntos
Magnaporthe/isolamento & purificação , Magnaporthe/fisiologia , Doenças das Plantas/microbiologia , Triticum/microbiologia , Magnaporthe/patogenicidade , Esporos Fúngicos/isolamento & purificação , Esporos Fúngicos/fisiologia , Zâmbia
18.
Sci Total Environ ; 740: 140015, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927537

RESUMO

Fall armyworm (FAW) is a new invasive pest that is causing devastating effects on maize production and threatening the livelihoods of millions of poor smallholders across sub-Saharan Africa and Asia. Using unique survey data from 2356 maize-growing households in Ghana, Rwanda, Uganda, Zambia and Zimbabwe, we examined how smallholder farmers are fighting this voracious pest. In particular, we assessed the FAW management strategies used by smallholders, socio-economic factors driving the choice of the management options, the complementarities or tradeoffs among the management options, and the (un)safe pesticide use practices of farmers. Results showed that smallholder farm households have adopted a variety of cultural, physical, chemical and local options to mitigate the effects of FAW, but the use of synthetic pesticides remains the most popular option. Results from multivariate probit regressions indicated that the extensive use of synthetic pesticides is driven by household asset wealth, and access to subsidised farm inputs and extension information. We observed that farm households are using a wide range of pesticides, including highly hazardous and banned products. Unfortunately, a majority of the households do not use personal protective equipment while handling the pesticides, resulting in reports of acute pesticide-related illness. Our findings have important implications for policies and interventions aimed at promoting environmentally friendly and sustainable ways of managing invasive pests in smallholder farming systems.


Assuntos
Espécies Introduzidas , Praguicidas , Spodoptera , Agricultura , Animais , Ásia , Gana , Ruanda , Uganda , Zâmbia , Zimbábue
19.
PLoS One ; 15(9): e0237931, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32911494

RESUMO

INTRODUCTION: We conducted an implementation science study to increase TB case detection through a combination of interventions at health facility and community levels. We determined the impact of the study in terms of additional cases detected and notification rate and compared the yield of bacteriologically confirmed TB of facility based and community based case finding. METHODOLOGY: Over a period of 18 months, similar case finding activities were conducted at George health facility in Lusaka Zambia and its catchment community, an informal peri-urban settlement. Activities included awareness and demand creation activities, TB screening with digital chest x-ray or symptom screening, sputum evaluation using geneXpert MTB/RIF, TB diagnosis and linkage to treatment. RESULTS: A total of 18,194 individuals were screened of which 9,846 (54.1%) were screened at the facility and 8,348 (45.9%) were screened in the community. The total number of TB cases diagnosed during the intervention period were 1,026, compared to 759 in the pre-intervention period; an additional 267 TB cases were diagnosed. Of the 563 bacteriologically confirmed TB cases diagnosed under the study, 515/563 (91.5%) and 48/563 (8.5%) were identified at the facility and in the community respectively (P<0.0001). The TB notification rate increased from 246 per 100,000 population pre-intervention to 395 per 100,000 population in the last year of the intervention. CONCLUSIONS: Facility active case finding was more effective in detecting TB cases than community active case finding. Strengthening health systems to appropriately identify and evaluate patients for TB needs to be optimised in high burden settings. At a minimum, provider initiated TB symptom screening with completion of the TB screening and diagnostic cascade should be provided at the health facility in high burden settings. Community screening needs to be systematic and targeted at high risk groups and communities with access barriers.


Assuntos
Efeitos Psicossociais da Doença , Instalações de Saúde , Características de Residência , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Adulto , Assistência à Saúde , Feminino , Geografia , Humanos , Masculino , Tuberculose/classificação , Zâmbia/epidemiologia
20.
Medicine (Baltimore) ; 99(39): e22415, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32991474

RESUMO

Kaposi sarcoma (KS) is an AIDS-defining angioproliferative malignancy associated with high morbidity and mortality. Most KS patients in regions with high incidence such as sub-Saharan Africa present late with advanced stage disease. Admitted KS patients have high mortality rates. Factors associated with mortality of admitted KS patients are poorly defined.We conducted a retrospective file review to ascertain reasons for admission and identify factors associated with mortality of admitted HIV-associated (epidemic) KS patients in Zambia. Baseline study variables were collected, and patients were retrospectively followed from admission to time of discharge or death.Mortality rate for admitted epidemic KS patients was high at 20%. The most common reasons for admission included advanced KS disease, severe anemia, respiratory tract infections, and sepsis. The majority (48%) of admitted patients had advanced clinical stage with visceral involvement on admission. Clinical predictors of mortality on univariate analysis included visceral KS [odds ratio (OR) = 13.74; 95% confidence interval (95% CI) = 1.68-113; P = 0.02), fever (OR = 26; 95% CI = 4.85-139; P = .001), and sepsis (OR = 35.56; 95% CI = 6.05-209; P = .001). Baseline hemoglobin levels (5.6 vs 8.2 g/dL; P = .001) and baseline platelet counts (63 x 10^9/L vs 205 x 10^9/L; P = .01) were significantly lower in mortalities vs discharges. Baseline white cell counts were higher in mortalities vs discharges (13.78 x 10^9/L vs 5.58 x 10^9/L; P = .01), and HIV-1 viral loads at the time of admission were higher in mortalities vs discharges (47,607 vs 40 copies/µL; P = .02). However, only sepsis (or signs and symptoms of sepsis) were independently associated with mortality after controlling for confounders.In conclusion, common reasons for admission of epidemic KS patients include advanced disease, severe anemia, respiratory tract infections, and signs and symptoms of sepsis. Signs and symptoms of sepsis are independent predictors of mortality in these patients.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Sarcoma de Kaposi/mortalidade , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente/estatística & dados numéricos , Estudos Retrospectivos , Adulto Jovem , Zâmbia/epidemiologia
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