Major Disease Outbreaks Research Articles

Evaluating case definitions for Ebola virus disease

In The Lancet Infectious Diseases, Grazia Caleo and colleagues1 report on the diagnostic usefulness of the WHO case definition for Ebola virus disease. Rapid identification of individuals potentially carrying an infection is among the most important concerns in the event of a major outbreak of an infectious disease. A valid case definition is key for the outbreak response, guiding diagnostic testing of individuals, based on which adequate medical management and transmission control measures are implemented.

The colliding epidemics of COVID-19, Ebola, and measles in the Democratic Republic of the Congo

The Democratic Republic of the Congo is facing major public health challenges due to a confluence of major outbreaks of Ebola virus disease, measles, and COVID-19.1–4 The tenth Ebola outbreak in eastern DR Congo began on Aug 1, 2018, and as of May 28, 2020, there have been 3406 Ebola virus disease cases with 2243 deaths. The Ebola virus disease outbreak was well controlled in northeast DR Congo following a multisectoral response, but four new confirmed Ebola cases were detected in northwest DR Congo on June 1, 2020, and an outbreak response is underway.

Inflammation, Immunity and Immunogenetics in COVID-19: A Narrative Review.

The novel Coronavirus Disease 2019 (COVID-19), that began in Wuhan Province, China was labelled as an International Public Health Emergency on January 30, 2020 and later was declared a pandemic by the World Health Organisation (WHO) on March 11, 2020. The causative agent, SARS-CoV-2 was the third coronavirus responsible for causing major disease outbreaks in human population after Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) caused by SARS-CoV and MERS-CoV respectively. The patients of COVID-19 present with a clinical feature resembling mild form of viral pneumonia which in certain cases progress to a severe form characterised by adult respiratory distress syndrome (ARDS) and/or multiorgan failure leading to death. The transition from mild to severe form of COVID-19 is affected by a lot of factors like age, co-morbidities etc. In the absence of an absolute cure, it is essential to explore the molecular pathogenesis of the disease to identify people at risk of developing severity so that alternative treatment modalities may be planned. The aim of this review is to provide an update on the general characteristics of SARS-CoV-2 and highlight the inflammatory changes and immune dysregulation that may help in identification of molecular predictors of disease severity.

Thoughts on Connections Between COVID-19 Pandemic And Climate Crisis

Thoughts on Connections Between COVID-19 Pandemic And Climate Crisis

Structural elucidation of SARS-CoV-2 vital proteins: Computational methods reveal potential drug candidates against main protease, Nsp12 polymerase and Nsp13 helicase

Recently emerged SARS-CoV-2 caused a major outbreak of coronavirus disease 2019 (COVID-19) and instigated a widespread fear, threatening global health safety. To date, no licensed antiviral drugs or vaccines are available against COVID-19 although several clinical trials are under way to test possible therapies. During this urgent situation, computational drug discovery methods provide an alternative to tiresome high-throughput screening, particularly in the hit-to-lead-optimization stage. Identification of small molecules that specifically target viral replication apparatus has indicated the highest potential towards antiviral drug discovery. In this work, we present potential compounds that specifically target SARS-CoV-2 vital proteins, including the main protease, Nsp12 RNA polymerase and Nsp13 helicase. An integrative virtual screening and molecular dynamics simulations approach has facilitated the identification of potential binding modes and favourable molecular interaction profile of corresponding compounds. Moreover, the identification of structurally important binding site residues in conserved motifs located inside the active site highlights relative importance of ligand binding based on residual energy decomposition analysis. Although the current study lacks experimental validation, the structural information obtained from this computational study has paved way for the design of targeted inhibitors to combat COVID-19 outbreak.

Phylogenetic Analysis and Structural Modeling of SARS-CoV-2 Spike Protein Reveals an Evolutionary Distinct and Proteolytically Sensitive Activation Loop

The 2019 novel coronavirus (2019-nCoV/SARS-CoV-2) originally arose as part of a major outbreak of respiratory disease centered on Hubei province, China. It is now a global pandemic and is a major public health concern. Taxonomically, SARS-CoV-2 was shown to be a Betacoronavirus (lineage B) closely related to SARS-CoV and SARS-related bat coronaviruses, and it has been reported to share a common receptor with SARS-CoV (ACE-2). Subsequently, betacoronaviruses from pangolins were identified as close relatives to SARS-CoV-2. Here, we perform structural modeling of the SARS-CoV-2 spike glycoprotein. Our data provide support for the similar receptor utilization between SARS-CoV-2 and SARS-CoV, despite a relatively low amino acid similarity in the receptor binding module. Compared to SARS-CoV and all other coronaviruses in Betacoronavirus lineage B, we identify an extended structural loop containing basic amino acids at the interface of the receptor binding (S1) and fusion (S2) domains. We suggest this loop confers fusion activation and entry properties more in line with betacoronaviruses in lineages A and C, and be a key component in the evolution of SARS-CoV-2 with this structural loop affecting virus stability and transmission.

Doing Geography in the Age of Coronavirus or How is Everybody Coping?

AAG - Doing Geography in the Age of Coronavirus or How is Everybody Coping? - All - You hear it from everyone you know: these are strange and frightening times. While most of us have witnessed major disease outbreaks from afar – Ebola, SARS, Swine Flu – it is another thing to encounter something so directly, so personally, so comprehensively. Pandemic: what once seemed part of a grim historical record has smashed into our contemporary reality.

The Comparison of Three Statistical Models for Syndromic Surveillance in Cattle Using Milk Production Data.

Two vector-borne infections have emerged and spread throughout the north-western part of Europe in the last decade: Bluetongue virus serotype-8 (BTV-8) and the Schmallenberg virus (SBV). The objective of the current study was to compare three statistical methods when applied in a syndromic surveillance context for the early detection of emerging diseases in cattle in the Netherlands. Since BTV-8 and SBV both have a negative effect on milk production in dairy cattle, routinely collected bulk milk recordings were used to compare the three statistical methods in their potential to detect drops in milk production during a period of seven years in which BTV-8 and SBV emerged. A Cusum algorithm, Bayesian disease mapping model, and spatiotemporal cluster analysis using the space-time scan statistic were performed and their performance in terms of sensitivity and specificity was compared. Spatiotemporal cluster analysis performed best for early detection of SBV in cattle in the Netherlands with a relative sensitivity of 71% compared to clinical surveillance and 100% specificity in a year without major disease outbreaks. Sensitivity to detect BTV-8 was low for all methods. However, many alerts of reduced milk production were generated several weeks before the week in which first clinical suspicions were reported. It cannot be excluded that these alerts represent the actual first signs of BTV-8 infections in cattle in the Netherlands thus leading to an underestimation of the sensitivity of the syndromic surveillance methods relative to the clinical surveillance in place.

Infections without borders: a new coronavirus in Wuhan, China.

Infections without borders: a new coronavirus in Wuhan, China.

Production cost and competitiveness in major salmon farming countries 2003–2018

This paper investigates the development of production costs in aquaculture of Atlantic salmon between the five main producer countries. A unique data set allows us to analyse the development in the period 2003 to 2018. Costs have developed differently between countries, with Chile and the Faroe Islands standing out with strong and different changes. Chile sees a strong increase in cost and moves from being the lowest to the highest cost producer, and then to lowest again. The Faroe Islands has the opposite development and moves from being the highest to one of the lowest cost producers. For Norway and Canada the changes are considerably smaller, while Scotland has had the most marked cost increase. For the Faroe Islands and Chile, major disease outbreaks play a major role in explaining the change in cost. Differences between countries are also related to scale, natural conditions, currency development and regulations. Results show that Norway's position as the leading salmon producing country in terms of market share seems justified by its low production cost.

Nigeria's Joint External Evaluation and National Action Plan for Health Security.

Nigeria is working to protect against and respond more effectively to disease outbreaks. Quick mobilization and control of the Ebola epidemic in 2014, at least 4 major domestic outbreaks each year, and significant progress toward polio eradication led to adoption of the World Health Organization's Global Health Security Joint External Evaluation (JEE) and National Action Plan for Health Security (NAPHS). The process required joint assessment and planning among many agencies, ministries, and sectors over the past 2 years. We carried out a JEE of 19 core programs in 2017 and launched a detailed NAPHS to improve prevention, detection, and response in December 2018, which required us to create topic-specific groups to document work to date and propose JEE scores. We then met with an international team for 5 days to review and revise scoring and recommendations, created a 5-year implementation plan, developed a management team to oversee implementation, drafted legislation to manage outbreaks, trained professionals at state and local levels of government, and set priorities among the many possible activities recommended. Management software and leadership skills were developed to monitor global health security programs. We learned to use international assistance strategically to strengthen planning and mentor national staff. Finally, a review of every major disease outbreak was used to prepare for the next challenge. Review and adaptation of this plan each year will be critical to ensure sustained momentum and progress. Many low-income countries are skilled at managing vertical disease control programs. Balancing and combining the 19 core activities of a country's public health system is a more demanding challenge.

Retrospective Study on the Occurrence of Reportable Priority Cattle Diseases in Southern Nations, Nationalities and Peoples’ Regional State, Southern Ethiopia

A retrospective study was conducted between October 2016 and March 2017 in Southern Nations, Nationalities and Peoples Regional State (SNNPRS) to identify major reportable cattle disease outbreaks. The retrospective study was based on a nine years (2007-2015) cattle disease outbreak report data retrieved from the Ministry of Livestock and Fisheries (MoLF) data bases. The retrospective study revealed that of the 15,840 disease outbreak reports expected from SNNPRS, only 1,578 (11%) reports were submitted to MoLF during the nine years’ time. According to the data retrieved from MoLF, a total of 1,496 cattle disease outbreaks with 44,646 morbidity cases and 4,709 mortalities were recorded in SNNPRS over the nine years period. The outbreaks were caused by blackleg (40.6%), hemorrhagic septicemia (HS) (26.3%), lumpy skin disease (LSD) (16%), anthrax (11.4%), foot and mouth disease (FMD) (4.7%), contagious bovine pleuropneumonia (CBPP) (0.8%) and rabies (0.3%) in decreasing order of their proportion. LSD was responsible for the highest proportion of morbidity cases (35.9%) followed by FMD (26.2%) while blackleg and LSD were the leading causes of cattle mortalities, which accounted for 31% and 30.2% of the deaths recorded, respectively. In contrast, the lowest number of outbreaks, morbidity and mortality of cattle was caused by rabies. Disease outbreaks were occurred in all the seasons of the year; however, relatively higher number of outbreaks (30.7%) was recorded in early dry season (September to November). 
 In conclusion, the retrospective study has shown a very low level of disease outbreak reporting rate in SNNPRS, which may be due to misreporting or no outbreak of diseases.

Clinical characteristics of two human-to-human transmitted coronaviruses: Corona Virus Disease 2019 vs. Middle East Respiratory Syndrome Coronavirus.

Subsequent to a global outbreak of the Middle East Respiratory Syndrome (MERS) in 2012, a novel human coronavirus, known as Corona Virus Disease 2019 (COVID-19) has caused a major disease outbreak. The aim of this study was to perform a systematic review to compare epidemiological, clinical, and laboratory features of COVID-19 and MERS-COV populations. We searched PubMed, EMBASE, and Cochrane Central Register of Controlled Trials database to identify potential studies that have reported COVID-19 or MERS-COV disease. Epidemiology, clinical, and laboratory outcomes, intensive care unit (ICU) admission rates, discharge rates, and fatality rates were evaluated using Graph-Pad Prism software. A total of forty-two studies were included in our research, involving in 4,720 patients (COVID-19 = 2,012, MERS-COV = 2,708). The present study revealed that main clinical manifestations of both COVID-19 and MERS-COV populations are fever, cough and generalized weakness or myalgia, and Acute Respiratory Distress Syndrome (ARDS) is the main complication. The COVID-19 population has a lower rate of ICU admissions, discharges, fatalities, and shorter incubation periods than those of MERS-COV population. The main clinical features of both COVID-19 and MERS-COV populations are fever, cough and generalized weakness or myalgia. ARDS is the main complication of both populations. COVID-19 cases have a shorter incubation period and lower rate of ICU admissions, discharges and fatalities compared to MRES-COV population.

Pandemics and epidemics: Past to present

Pandemics and epidemics befall almost every decade. History documents pandemics since 430 BC. Each outbreak is suspected to be related to a minuscule creature which is new to the world or with a mutation. In recent years, viruses have caused multiple disease outbreaks leading to significant global public health menace. Although we have moved and reached new heights in modern scientific medicine, there remains a gap in understanding of environmental risk factors, disease pathogenesis and apt approach towards its management. This article outlines the major disease outbreaks that affected global proportions and had a marked impact on the human civilisation, starting with historical outbreak of plague, Spanish flu, severe acute respiratory syndrome, Ebola, Zika, Nipah and Middle East respiratory syndrome to the most recent coronavirus disease 2019.

Meningococcal Vaccine for Hajj Pilgrims: Compliance, Predictors, and Barriers.

Background: Major intercontinental outbreaks of invasive meningococcal disease associated with the Hajj occurred in 1987, 2000, and 2001. Mandatory meningococcal vaccination for all pilgrims against serogroups A and C and, subsequently, A, C, W, and Y controlled the epidemics. Overseas pilgrims show excellent adherence to the policy; however, vaccine uptake among domestic pilgrims is suboptimal. This survey aimed to evaluate meningococcal vaccine uptake among Hajj pilgrims and to identify key factors affecting this. Methods: An anonymous cross-sectional survey was conducted among pilgrims in Greater Makkah during the Hajj in 2017–2018. Data on socio-demographic characteristics, vaccination status, cost of vaccination, and reasons behind non-receipt of the vaccine were collected. Results: A total of 509 respondents aged 13 to 82 (median 33.8) years participated in the survey: 86% male, 85% domestic pilgrims. Only 389/476 (81.7%) confirmed their meningococcal vaccination status; 64 individuals (13.4%), all domestic pilgrims, did not receive the vaccine, and 23 (4.8%) were unsure. Among overseas pilgrims, 93.5% certainly received the vaccine (6.5% were unsure) compared to 80.9% of domestic pilgrims (p < 0.01). Being employed and having a tertiary qualification were significant predictors of vaccination adherence (odds ratio (OR) = 2.2, 95% confidence interval (CI) = 1.3–3.8, p < 0.01; and OR = 1.7, CI = 1–2.5, p < 0.05, respectively). Those who obtained pre-Hajj health advice were more than three times as likely to be vaccinated than those who did not (OR = 3.3, CI = 1.9–5.9, p < 0.001). Lack of awareness (63.2%, 36/57) and lack of time (15.8%, 9/57) were the most common reasons reported for non-receipt of vaccine. Conclusion: Many domestic pilgrims missed the compulsory meningococcal vaccine; in this regard, lack of awareness is a key barrier. Being an overseas pilgrim (or living at a distance from Makkah), receipt of pre-Hajj health advice, and employment were predictors of greater compliance with the vaccination policy. Opportunities remain to reduce the policy–practice gap among domestic pilgrims.

Pandemic influenza and major disease outbreak preparedness in US emergency departments: A survey of medical directors and department chairs.

To quantify the readiness of individual academic emergency departments (EDs) in the United States for an outbreak of pandemic influenza. Methods, design, and setting: Cross-sectional assessment of influenza pandemic preparedness level of EDs in the United States via survey of medical directors and department chairs from the 135 academic emergency medicine departments in the United States. Preparedness assessed using a novel score of 15 critical preparedness indicators. Data analysis consisted of summary statistics, χ2, and ANOVA. ED medical directors and department chairs. One hundred and thirty academic emergency medicine departments contacted; 66 (50.4 percent) responded. Approximately half (56.0 percent) stated their ED had a written plan for pandemic influenza response. Mean preparedness score was 7.2 (SD = 4.0) out of 15 (48.0 percent); only one program (1.5 percent) achieved a perfect score. Respondents from programs with larger EDs (=30 beds) were more likely to have a higher preparedness score (p < 0.035), an ED pandemic preparedness plan (p = 0.004) and a hospital pandemic preparedness plan (p = 0.007). Respondents from programs with larger EDs were more likely to feel that their ED was prepared for a pandemic or other major disease outbreak (p = 0.01). Only one-third (34.0 percent) felt their ED was prepared for a major disease outbreak, and only 27 percent felt their hospital was prepared to respond to a major disease outbreak. Significant deficits in preparedness for pandemic influenza and other disease outbreaks exist in US EDs, relative to HHS guidelines, which appear to be related in part to ED size. Further study should be undertaken to determine the barriers to appropriate pandemic preparedness, as well as to develop and validate preparedness metrics.

Pandemic influenza and major disease outbreak preparedness in US emergency departments: A selected survey of emergency health professionals.

To assess the level of pandemic preparedness at emergency departments (EDs) around the country and to better understand current barriers to preparedness in the United States represented by health professionals in the American College of Emergency Physician (ACEP) Disaster Medicine Section (DMS). Methods, design, and setting: A cross-sectional survey of ACEP DMS members was performed. A total of 300 members were surveyed both via e-mail and with paper surveys during the 2009 ACEP Scientific Assembly DMS Meeting. An optional comments section was included for section members' perspectives on barriers to preparedness. A 15-item pandemic preparedness score was calculated for each respondent based on key preparedness indicators as defined by the authors. Results were analyzed with descriptive statistics, χ2 analysis, Cochran-Armitage trend test, and analysis of variance. Free text comments were coded and subjected to frequency-based analysis. A total of 92 DMS members completed the survey with a response rate of 31 percent. Although 85 percent of those surveyed indicated that their hospital had a plan for pandemic influenza response and other infectious disease threats, only 68 percent indicated that their ED had a plan, and 52 percent indicated that their hospital or ED had conducted disaster preparedness drills. Only 57 percent indicated that there was a plan to augment ED staff in the event of a staffing shortage, and 63 percent indicated that there were adequate supplies of personal protective equipment. While 63 percent of respondents indicated that their ED had a plan for distribution of vaccines and antivirals, only 32 percent of EDs had a plan for allocation of ventilators. A total of 42 percent of respondents felt that their ED was prepared in the event of a pandemic influenza or other disease outbreak, and only 35 percent felt that their hospital was prepared. The average pandemic preparedness score among respondents was 8.30 of a total of 15. Larger EDs were more likely to have a higher preparedness score (p = 0.03) and more likely to have a pandemic preparedness plan (p = 0.037). Some major barriers to preparedness cited by section members included lack of local administration support, challenges in funding, need for dedicated disaster preparedness personnel, staffing shortages, and a lack of communication among disaster response agencies, particularly at the federal level. There appear to be significant gaps in pandemic influenza and other infectious disease outbreak planning among the hospitals where ACEP DMS members work. This may reflect a broader underlying inadequacy of preparedness measures.

A study of clinical manifestations and complications of dengue fever in medical college hospital

Background: Dengue, the most common arboviral disease worldwide is usually endemic but several epidemics have been recorded. Global incidence of dengue has grown dramatically in recent decades; about half of the world's population is now at risk. The situation in India is reflected by occurrence of major disease outbreaks from time to time over the last few decades. Objectives: The objective of the present study was to observe the various clinical manifestations and complications of dengue fever. Materials and Methods: Study included 100 patients admitted to medicine ward in medical college hospital for a period of 6 months with symptoms and signs suggestive of dengue fever and those positive for NS1Ag, IgM and IgG dengue antibodies using Rapid strip test. Results: Among 100 patients observed, majority cases were dengue fever (92%) with no mortality, 5% were dengue hemorrhagic fever (DHF) with mortality 20% and 3% were dengue shock syndrome (DSS) with mortality 67%. 71 were males and 29 were females with sex ratio 2.5:1. Maximum patients were in the age group of 18-30years. Most common clinical manifestations were fever (100%), headache (90%), abdominal pain (72%), arthralgia (65%), myalgia (64%), hepatomegaly (52%) and splenomegaly (41%). Thrombocytopenia (84%) is the most common hematological abnormality observed. Among serology positivity, majority were positive for NS1 antigen (81%), followed by IgM antibodies (7%) and mixed positivity (12%). Most common complication observed was hepatic dysfunction (33%). Conclusion: Dengue infection is common viral infection with varying clinical manifestations from region to region and epidemic to epidemic. Even though no specific treatment available for dengue fever but early diagnosis and timely intervention will prevent complications and mortality from dengue hemorrhagic fever and dengue shock syndrome.

Systematic Review of Important Bacterial Zoonoses in Africa in the Last Decade in Light of the 'One Health' Concept.

Zoonoses present a major public health threat and are estimated to account for a substantial part of the infectious disease burden in low-income countries. The severity of zoonotic diseases is compounded by factors such as poverty, living in close contact with livestock and wildlife, immunosuppression as well as coinfection with other diseases. The interconnections between humans, animals and the environment are essential to understand the spread and subsequent containment of zoonoses. We searched three scientific databases for articles relevant to the epidemiology of bacterial zoonoses/zoonotic bacterial pathogens, including disease prevalence and control measures in humans and multiple animal species, in various African countries within the period from 2008 to 2018. The review identified 1966 articles, of which 58 studies in 29 countries met the quality criteria for data extraction. The prevalence of brucellosis, leptospirosis, Q fever ranged from 0–40%, 1.1–24% and 0.9–28.2%, respectively, depending on geographical location and even higher in suspected outbreak cases. Risk factors for human zoonotic infection included exposure to livestock and animal slaughters. Dietary factors linked with seropositivity were found to include consumption of raw milk and locally fermented milk products. It was found that zoonoses such as leptospirosis, brucellosis, Q fever and rickettsiosis among others are frequently under/misdiagnosed in febrile patients seeking treatment at healthcare centres, leading to overdiagnoses of more familiar febrile conditions such as malaria and typhoid fever. The interactions at the human–animal interface contribute substantially to zoonotic infections. Seroprevalence of the various zoonoses varies by geographic location and species. There is a need to build laboratory capacity and effective surveillance processes for timely and effective detection and control of zoonoses in Africa. A multifaceted ‘One Health’ approach to tackle zoonoses is critical in the fight against zoonotic diseases. The impacts of zoonoses include: (1) Humans are always in contact with animals including livestock and zoonoses are causing serious life-threatening infections in humans. Almost 75% of the recent major global disease outbreaks have a zoonotic origin. (2) Zoonoses are a global health challenge represented either by well-known or newly emerging zoonotic diseases. (3) Zoonoses are caused by all-known cellular (bacteria, fungi and parasites) and noncellular (viruses or prions) pathogens. (4) There are limited data on zoonotic diseases from Africa. The fact that human health and animal health are inextricably linked, global coordinated and well-established interdisciplinary research efforts are essential to successfully fight and reduce the health burden due to zoonoses. This critically requires integrated data from both humans and animals on zoonotic diseases.

Identification of a novel cluster of PCV2 isolates from Meghalaya, India indicates possible recombination along with changes in capsid protein

Documentation of the emergence of Porcine circovirus 2 (PCV2) infection and economic losses incurred due to high mortality has been reported worldwide. The prevalence and genetic diversity of the virus has been reported in Northeast India including the possible chances of Classical swine fever virus (CSFV) vaccine failure in pig population in this region resulting in major disease outbreak. Irrespective of the genetic variability, the emergence of a novel cluster (based on the ORF2 phylogeny) was reported last year. The present study describes a state-wide (Meghalaya, India) molecular epidemiological investigation of PCV2 strains in pig population by amplification, sequencing and undertaking phylogenetic analyses. The results indicate the identification of a novel cluster of PCV2 originating from the inter-genotypic recombination between PCV2c and PCV2d. Multiple sequence alignment of amino acids indicates possible substitution in the A, B and C domains of the capsid protein. Molecular structural modelling of the capsid protein of PCV2 indicated possible motif variations in the secondary structure including presence of a tunnel, encountered at the interface region on each chain facilitating in transportation of molecules and acting as an active site for attachment and penetration. The baseline data strengthens the existing control programme of PCV2 and is possibly helpful in the planning of active surveillance strategy in this region.