scholarly journals Epidemiology and Laboratory Diagnostics of Dengue, Yellow Fever, Zika, and Chikungunya Virus Infections in Africa

Pathogens ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1324
Author(s):  
Awadalkareem Adam ◽  
Christian Jassoy
Keyword(s):  
Yellow Fever ◽  
Healthcare Providers ◽  
Epidemiological Data ◽  
Unknown Etiology ◽  
Laboratory Diagnostics ◽  
Surveillance Systems ◽  
Virus Infections ◽  
African Countries ◽  
Diagnostic Laboratory ◽  
Epidemiologic Surveillance

Arbovirus infections are widespread, and their disease burden has increased in the past decade. In Africa, arbovirus infections and fever with unknown etiology are common. Due to the lack of well-established epidemiologic surveillance systems and accurate differential diagnosis in most African countries, little is known about the prevalence of human arbovirus infections in Africa. The aim of this review is to summarize the available epidemiological data and diagnostic laboratory tools of infections with dengue, yellow fever, Zika, and chikungunya viruses, all transmitted by Aedes mosquitoes. Studies indicate that these arboviral infections are endemic in most of Africa. Surveillance of the incidence and prevalence of the infections would enable medical doctors to improve the diagnostic accuracy in patients with typical symptoms. If possible, arboviral diagnostic tests should be added to the routine healthcare systems. Healthcare providers should be informed about the prevalent arboviral diseases to identify possible cases.

Crowdsourcing Covid-19 signals in sub-Saharan Africa: Leveraging digital contributor networks for participatory surveillance of Covid-19 symptoms and deaths (Preprint)

2020 ◽  
Author(s):  
Ngozi A Erondu ◽  
Sagal A Ali ◽  
Mohamed Ali ◽  
Schadrac C Agbla
Keyword(s):  
Public Health ◽  
Sub Saharan Africa ◽  
Specific Information ◽  
Surveillance Systems ◽  
Health Seeking ◽  
African Countries ◽  
Cross Sectional Survey ◽  
Local Networks ◽  
The World ◽  
Sub Saharan

BACKGROUND In sub-Saharan Africa, underreporting of cases and deaths has been attributed to various factors including, weak disease surveillance, low health-seeking behaviour of flu like symptoms, and stigma of Covid-19. There is evidence that SARS-CoV-2 spread mimics transmission patterns of other countries across the world. Since the Covid-19 pandemic has changed the way research can be conducted and in light of restrictions on travel and risks to in-person data collection, innovative approaches to collecting data must be considered. Nearly 50% of Africa’s population is a unique mobile subscriber and it is one of the fastest growing smart-phone marketplaces in the world; hence, mobile phone platforms should be considered to monitor Covid-19 trends in the community. OBJECTIVE We demonstrate the use of digital contributor platforms to survey individuals about cases of flu-like symptoms and instances of unexplained deaths in Ethiopia, Kenya, Nigeria, Somalia, and Zimbabwe. METHODS Rapid cross-sectional survey of individuals with severe flu and pneumonia symptoms and unexplained deaths in Ethiopia, Kenya, Nigeria, Somalia and Zimbabwe RESULTS Using a non-health specific information platform, we found COVID-19 signals in five African countries, specifically: •Across countries, nearly half of the respondents (n=739) knew someone who had severe flu or pneumonia symptoms in recent months. •One in three respondents from Somalia and one in five from Zimbabwe respondents said they knew more than five people recently displaying flu and/or pneumonia symptoms. •In Somalia there were signals that a large number of people might be dying outside of health facilities, specifically in their homes or in IDP or refugee camps. CONCLUSIONS Existing digital contributor platforms with local networks are a non-traditional data source that can provide information from the community to supplement traditional government surveillance systems and academic surveys. We demonstrate that using these distributor networks to for community surveys can provide periodic information on rumours but could also be used to capture local sentiment to inform public health decision-making; for example, these insights could be useful to inform strategies to increase confidence in Covid19 vaccine. As Covid-19 continues to spread somewhat silently across sub-Saharan Africa, regional and national public health entities should consider expanding event-based surveillance sources to include these systems.

Using novel methodologies to support burden of disease estimates

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
T Hald
Keyword(s):  
International Development ◽  
Traditional Approach ◽  
Source Population ◽  
Surveillance Systems ◽  
Data Generation ◽  
Time Data ◽  
African Countries ◽  
Indirect Measure ◽  
True Incidence ◽  
Laboratory Capacity

Abstract A challenge to estimating burden of diarrheal diseases, particularly in LMICs, where laboratory capacity and surveillance systems are limited, is obtaining valid estimates of etiology proportions of cases. A commonly used method is systematic review of studies reporting pathogen isolation in diarrhea cases. However, studies often differ in design, source population, timeframe, and pathogens included, hampering extrapolation to the target population. In a study co-funded by the Bill and Melinda Gates Foundation and the UK Department for International Development, we explore a novel approach for estimating diarrhea etiology proportions in urban and rural populations in four African countries. We analyse sewage samples using short-read next-generation sequencing (NGS) to determine abundance of genes that can be mapped to specific bacterial genera, providing an estimate of the relative abundance of specific pathogens in each sample. In parallel to collecting sewage samples, a questionnaire-based population survey will estimate diarrheal incidence. By combining results, pathogen-specific incidence will be estimated and compared with incidence estimates from the traditional approach. The application NGS to human sewage has great potential for surveillance of foodborne infections, particularly in resource-poor settings where laboratory capacity for bacterial isolation is limited. First, NGS is a one method takes all approach, as it is based on detection of RNA/DNA, a language common across pathogens. Second, it is culture independent, allowing for real-time data generation and standardized sharing. Finally, few samples are needed to survey large populations for several pathogens at the same time. Thus, surveillance based on NGS of sewage may prove to be an indirect measure of incidence. Although it will not provide an estimate for the true incidence in the population, it will increase our understanding of the burden and as such be a proxy and novel way of ranking diseases.

scholarly journals Different Cross-Reactivities of IgM Responses in Dengue, Zika and Tick-Borne Encephalitis Virus Infections

Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 596
Author(s):  
Karin Stiasny ◽  
Stefan Malafa ◽  
Stephan W. Aberle ◽  
Iris Medits ◽  
Georgios Tsouchnikas ◽  
...  
Keyword(s):  
Dengue Virus ◽  
Yellow Fever ◽  
Vaccination Coverage ◽  
Virus Infections ◽  
Recent Infection ◽  
Specific Diagnosis ◽  
Virus Particles ◽  
Tick Borne Encephalitis ◽  
Structural Peculiarities ◽  
Tick Borne Encephalitis Virus

Flaviviruses circulate worldwide and cause a number of medically relevant human diseases, such as dengue, Zika, yellow fever, and tick-borne encephalitis (TBE). Serology plays an important role in the diagnosis of flavivirus infections, but can be impeded by antigenic cross-reactivities among flaviviruses. Therefore, serological diagnosis of a recent infection can be insufficiently specific, especially in areas where flaviviruses co-circulate and/or vaccination coverage against certain flaviviruses is high. In this study, we developed a new IgM assay format, which is well suited for the specific diagnosis of TBE, Zika and dengue virus infections. In the case of TBE and Zika, the IgM response proved to be highly specific for the infecting virus. In contrast, primary dengue virus infections induced substantial amounts of cross-reactive IgM antibodies, which is most likely explained by structural peculiarities of dengue virus particles. Despite the presence of cross-reactive IgM, the standardized nature and the quantitative read-out of the assay even allowed the serotype-specific diagnosis of recent dengue virus infections in most instances.

scholarly journals Liposomal Systems as Nanocarriers for the Antiviral Agent Ivermectin

2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Romina Croci ◽  
Elisabetta Bottaro ◽  
Kitti Wing Ki Chan ◽  
Satoru Watanabe ◽  
Margherita Pezzullo ◽  
...  
Keyword(s):  
Yellow Fever ◽  
Rna Virus ◽  
Multiorgan Failure ◽  
Antiviral Agent ◽  
Drug Carriers ◽  
Virus Infections ◽  
Starting Point ◽  
Significant Public Health ◽  
High Cytotoxicity

RNA virus infections can lead to the onset of severe diseases such as fever with haemorrhage, multiorgan failure, and mortality. The emergence and reemergence of RNA viruses continue to pose a significant public health threat worldwide with particular attention to the increasing incidence of flaviviruses, among others Dengue, West Nile Virus, and Yellow Fever viruses. Development of new and potent antivirals is thus urgently needed. Ivermectin, an already known antihelminthic drug, has shown potent effectsin vitroonFlavivirushelicase, with EC50values in the subnanomolar range for Yellow Fever and submicromolar EC50for Dengue Fever, Japanese encephalitis, and tick-borne encephalitis viruses. However ivermectin is hampered in its application by pharmacokinetic problems (little solubility and high cytotoxicity). To overcome such problems we engineered different compositions of liposomes as ivermectin carriers characterizing and testing them on several cell lines for cytotoxicity. The engineered liposomes were less cytotoxic than ivermectin alone and they showed a significant increase of the antiviral activity in all the Dengue stains tested (1, 2, and S221). In the current study ivermectin is confirmed to be an effective potential antiviral and liposomes, as drug carriers, are shown to modulate the drug activity. All together the results represent a promising starting point for future improvement of ivermectin as antiviral and its delivery.

Organization of the work of the medical laboratory service in accordance with the requirements of the standard GOST ISO 15189–2015 «Medical laboratories. Particular requirements for quality and competence»

2020 ◽  
pp. 15-22
Author(s):  
Elena Vitalievna Perminova
Keyword(s):  
Clinical Laboratory ◽  
Medical Laboratory ◽  
Laboratory Research ◽  
Laboratory Diagnostics ◽  
Clinical Diagnostic Laboratory ◽  
Diagnostic Laboratory ◽  
Iso 15189 ◽  
Laboratory Service ◽  
Medical Laboratories

Clinical laboratory diagnostics is a medical specialty, which is based on in vitro diagnostic studies of biomaterial obtained from an individual. At the present stage, there are three main types of organization of the laboratory research process — a laboratory service as part of a medical and preventive institution, a centralized laboratory where biomaterials are delivered for research from various healthcare institutions, as well as mobile laboratories that allow conducting the research directly at the patient’s bedside. This discipline involves the use of a wide variety of diagnostic research methods and the use of a huge number of specific techniques. Their list should include carrying out hematological, microbiological, virological, immunological, serological, parasitic, and biochemical studies. Also, when organizing laboratory diagnostic activities, a number of other studies (cytological, histological, toxicological, genetic, molecular biological, etc.) are provided. A laboratory report is formulated after obtaining clinical data and comparing them with the obtained test results. The quality of laboratory tests is ensured through the systematic implementation of internal laboratory control, as well as participation in a national program for external quality assessment. The activities of the clinical diagnostic laboratory should be organized in accordance with the requirements of the standard GOST R ISO 15189–2015 «Medical laboratories. Particular requirements for quality and competence», which is based on the provisions of two more fundamental standards — ISO 9001 and ISO 17025, and adds a number of special requirements related to medical laboratories.

scholarly journals The Neglect and Fast Spread of Some Arboviruses: A Note for Healthcare Providers in Nigeria

Diseases ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 99
Author(s):  
Olatunji Kolawole ◽  
Adebimpe Seriki ◽  
Ahmad Irekeola ◽  
Jeremiah Ogah
Keyword(s):  
Rift Valley Fever ◽  
Healthcare Providers ◽  
Epidemiological Data ◽  
Valley Fever ◽  
Health Burden ◽  
Depth Analysis ◽  
Health Practitioners ◽  
Missed Diagnosis ◽  
Significant Health ◽  
Diagnosis Of Diseases

Arboviruses are distributed worldwide and constitute significant health burden globally. Outbreaks of arboviruses have been reported in Africa and beyond. In Nigeria, like in many other countries, arbovirus infections are more often than not neglected. As the early clinical features of arbovirus infections are generally nonspecific, most healthcare providers mistake them for other diseases. Outbreaks have been reported in Africa and beyond. The consequence of missed diagnosis of diseases cannot be overstated. In this review, some epidemiological data, classical syndromes, and risk factors for five human arboviruses (yellow fever YF, dengue DENV, chikungunya CHIKV, Rift Valley fever RVF, and West Nile virus WNV) found in Nigeria are presented. Health practitioners should ensure in-depth analysis rather than a superficial diagnosis of diseases before declaring a course of treatment.

scholarly journals COVID 19 Dawn from Wuhan: “The Number Game”

2020 ◽  
Vol 32 (3) ◽  
pp. 564-568
Author(s):  
Sumit Chawla ◽  
Harinder Singh ◽  
Bharti Chawla
Keyword(s):  
Case Fatality ◽  
Epidemiological Data ◽  
Unknown Etiology ◽  
The Novel ◽  
Time Data ◽  
Public Health Response ◽  
Expected Time ◽  
Hospitalization Rates ◽  
Health Response ◽  
Novel Virus

On 31st December 2019, China informed local WHO office of "cases of pneumonia of unknown etiology detected in Wuhan. As of 6th May 2020, there are nearly 3.6 million cases of corona virus infection and approximately 0.25 million deaths worldwide. The real-time data regarding the actual number of cases, as it originates from the epicenter is the key to the estimation of the case fatality rate, hospitalization rates, expected timeline of arrival of contagion, and other epidemiological data. The novel virus has no available literature pertaining to its epidemiological parameters, on which experts can base their estimates and hence the challenge in planning for epidemic management. Bolstering this challenge are the reports alleging under-reporting by Chinese authorities. Alleged toned down numbers could have led to erroneously low estimates contributing to inadequate public health response globally. We conducted a simulation on epidemiological model of COVID-19 to find out expected time off arrival of infections and mortality in different countries and compared this to actual data.

scholarly journals Excess mortality in Guadeloupe and Martinique, islands of the French West Indies, during the chikungunya epidemic of 2014

2018 ◽  
Vol 146 (16) ◽  
pp. 2059-2065 ◽  
Author(s):  
A. R. R. Freitas ◽  
P. M. Alarcón-Elbal ◽  
M. R. Donalisio
Keyword(s):  
Strong Correlation ◽  
Excess Mortality ◽  
Pearson Correlation ◽  
Age Groups ◽  
Epidemiological Data ◽  
Mortality Data ◽  
Surveillance Systems ◽  
Mortality And Morbidity ◽  
The Impact ◽  
Excess Deaths

AbstractIn some chikungunya epidemics, deaths are not completely captured by traditional surveillance systems, which record case and death reports. We evaluated excess deaths associated with the 2014 chikungunya virus (CHIKV) epidemic in Guadeloupe and Martinique, Antilles. Population (784 097 inhabitants) and mortality data, estimated by sex and age, were accessed from the Institut National de la Statistique et des Études Économiques in France. Epidemiological data, cases, hospitalisations and deaths on CHIKV were obtained from the official epidemiological reports of the Cellule de Institut de Veille Sanitaire in France. Excess deaths were calculated as the difference between the expected and observed deaths for all age groups for each month in 2014 and 2015, considering the upper limit of 99% confidence interval. The Pearson correlation coefficient showed a strong correlation between monthly excess deaths and reported cases of chikungunya (R= 0.81,p< 0.005) and with a 1-month lag (R= 0.87,p< 0.001); and a strong correlation was also observed between monthly rates of hospitalisation for CHIKV and excess deaths with a delay of 1 month (R= 0.87,p< 0.0005). The peak of the epidemic occurred in the month with the highest mortality, returning to normal soon after the end of the CHIKV epidemic. There were excess deaths in almost all age groups, and excess mortality rate was higher among the elderly but was similar between male and female individuals. The overall mortality estimated in the current study (639 deaths) was about four times greater than that obtained through death declarations (160 deaths). Although the aetiological diagnosis of all deaths associated with CHIKV infection is not always possible, already well-known statistical tools can contribute to the evaluation of the impact of CHIKV on mortality and morbidity in the different age groups.

Medical and Economics Benefits of Tele-expertise in Dermatology: Case study in eight Health Centers in Mali.

2020 ◽  
Author(s):  
Cheick Oumar Bagayoko ◽  
Mahmoud Cissé ◽  
Joseph Aka ◽  
Adama Dicko ◽  
Abdrahamane Anne ◽  
...  
Keyword(s):  
Health Professionals ◽  
Medical Condition ◽  
Healthcare Providers ◽  
Cross Sectional Study ◽  
Economic Benefits ◽  
Expert Advice ◽  
Financial Benefit ◽  
African Countries ◽  
Cross Sectional ◽  
Specialized Care

Abstract Background: Mali, like many Sub-Saharan African countries, is experiencing an acute crisis with respect to the shortage of qualified health professionals. This crisis is even more acute when it comes to specialized medical fields such as dermatology. To address this shortage, a tele-dermatology project has been launched in Mali since 2015 in order to provide access to specialized care to the most remote populations.Objective: The aim of our study is to assess the medico-economic benefits of the pilot phase of this project.Methods: We conducted a retrospective cross-sectional study of all requests for expert advice sent to dermatology experts through the "Bogou" tele-expertise platform.The sample consisted of 52 patients at eight remote sites and ten health professionals, including 4 specialists.The economic study was done using a parameter of cost analysis and the professional evaluation of healthcare providers. It compared consultation and transportation fees (on-site and off-site), and used a questionnaire assessing items on a 5-level Lickert scale and open-ended questions to evaluate the satisfaction of health professionals. Data analysis was performed by SPSS v25.Results: During the period, 374 requests for tele-expertise were made for the benefit of 52 patients. 89.3% of requests were answered by specialists, with an average response time of 46 hours 59 minutes and extremes from 7 minutes to 415 hours 4 minutes. Eczema was the most common medical condition diagnosed. 98% of patients had never completed a dermatological consultation because of a lack of means to travel to the only specialized center in the country. Consequently, they were all very satisfied or satisfied with the tele-expertise service. The 52 participating patients in project have realized a great financial benefit. Together they saved an average of 5,824,500 XOF (9429 euros).All the health professionals surveyed also expressed satisfaction with the application. They confirmed that the project has enabled them to strengthen their skills in the management of dermatological pathologies.Conclusion: Based on the results of our study, we can say that tele-dermatology allows access to specialized care and a reduction in the costs of care for patients in remote areas.

5. Emerging virus infections

2018 ◽  
pp. 49-62
Author(s):  
Dorothy H. Crawford
Keyword(s):  
Yellow Fever ◽  
Rift Valley ◽  
Domestic Animals ◽  
Life Cycles ◽  
Virus Spread ◽  
Virus Infections ◽  
West Nile ◽  
Economic Implications ◽  
Emerging Virus ◽  
Contaminated Blood

Arboviruses are generally transmitted by small biting insects such as mosquitoes. These insects are not just passive carriers of the viruses, but are required by the viruses to complete their life cycles. So arboviruses cannot pass directly from one victim to another except rarely by transfusion of contaminated blood or transplantation of an infected organ. Nevertheless, these viruses are spreading widely, causing large epidemics in humans and domestic animals, with increasing morbidity, mortality, and severe economic implications. ‘Emerging virus infections: arthropod-transmitted viruses’ describes the yellow fever, Zika, Chikungunya, West Nile, dengue fever, and Rift Valley viruses. As the emergence and re-emergence of viruses is increasing, vaccines to protect both humans and domestic animals and to prevent virus spread are urgently needed.

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