Endemic Infectious Diseases Research Articles

An initiative to develop a public engagement ecosystem in Ghana: a case of WACCBIP’s High Schools’ Engagement Programme

Background: The High Schools Engagement Programme (HSEP), is a West African Centre for Cell Biology of Infectious Pathogens (WACCBIP) public engagement initiative that targets students in under-resourced high schools in Ghana. Annual programmes are directed towards providing information on prospective careers in Science and discussing the causes of and preventive measures against endemic infectious diseases. Using peer-learning strategies, post-undergraduate research trainees (graduate interns) encourage collective action against the diseases and work to inspire high school students to consider scientific research as a career, either directly or in support roles. The objective of this study was to explore the outcomes of the HSEP, specifically revealing how it met its initial objectives, and other relevant unintended outcomes. Methods: An evaluation design, which relied on a survey and interviews of 138 high school students, 9 graduate interns, and 3 teachers who participated in the 2019 edition of the HSEP, was employed. Results: The HSEP presented a likelihood of improving the academic performance of high school students and provided motivation for them to pursue careers in scientific research. The programme also equipped the students with requisite knowledge to contribute to the prevention of infectious diseases prevalent in their communities. As trainee scientists, graduate interns also developed awareness on the need for public engagement, the challenges of STEM education in Ghana and the need to make efforts to address these challenges, and also developed key leadership and soft skills. Conclusions: Overall, the HSEP could potentially be a model for developing a public engagement ecosystem in Ghana. It is recommended that the programme is scaled up to include master’s degree and PhD researchers as facilitators to further widen the favorable impacts.

On the origin of the genetic variation in infectious disease prevalence: Genetic analysis of disease status versus infections for Digital Dermatitis in Dutch dairy cattle.

The purpose of this study was to investigate the origin of the genetic variation in the prevalence of bovine digital dermatitis (DD) by comparing a genetic analysis of infection events to a genetic analysis of disease status. DD is an important endemic infectious disease affecting the claws of cattle. For disease status, we analysed binary data on individual disease status (0,1; indicating being free versus infected), whereas for infections, we analysed binary data on disease transmission events (1,0; indicating becoming infected or not). The analyses of the two traits were compared using cross‐validation. The analysis of disease status captures a combination of genetic variation in disease susceptibility and the ability of individuals to recover, whereas the analysis of infections captures genetic variation in susceptibility only. Estimated genetic variances for both traits indicated substantial genetic variation. The GEBV for disease status and infections correlated with only 0.60, indicating that both models indeed capture distinct information. Together, these results suggest the presence of genetic variation not only in disease susceptibility, but also in the ability of individuals to recover from DD. We argue that the presence of genetic variation in recovery implies that breeders should distinguish between infected individuals versus infectious individuals. This is because epidemiological theory shows that selection for recovery is effective only when it targets recovery from being infectious.

Seroprevalence and risk factors for lumpy skin disease in cattle in Northern Egypt.

Lumpy skin disease (LSD) is an endemic infectious viral disease of cattle in African and Middle East countries. A cross-sectional study was conducted to determine the seroprevalence of LSD among cattle in Northern Egypt and assessed the associated risk factors with LSD infection. A total of 1000 sera samples were collected from cattle and examined serologically with commercial ELISA kit. Overall, the true seroprevalence of LSD among cattle in Egypt was 19.5% (n = 180). The true seroprevalence rate was varied significantly between different geographical studied areas, and the highest level was observed in Kafr El-Sheikh (26.7%) and Gharbia (23.7%) governorates. Moreover, the risk of getting LSD infection was increased among Holstein breed (OR = 4.586; 95%CI, 1.83-11.48) and adult cattle (OR = 2.498; 95%CI, 1.17-5.32) during summer season (OR = 7.303, 95%CI: 3.97-13.42). Furthermore, communal grazing (OR = 1.546; 95%CI, 0.91-2.60), communal water points (OR = 3.283; 95%CI, 2.11-5.09), introduction of new animal (OR = 2.216; 95%CI, 1.32-3.71), and contact with other animals (OR = 3.401; 95%CI, 1.62-7.10) were identified as significant risk factors for the occurrence of LSDV infection in cattle. Moreover, the present study revealed that no significant (P > 0.05) association between sex or type of herd and occurrence of LSD infection.

Seroprevalence of selected endemic infectious diseases in large-scale Estonian dairy herds and their associations with cow longevity and culling rates

Herd culling rates and longevity represent herd health and welfare status as well as farm economic performance. The contribution of endemic circulation of the main cattle pathogens to herd performance has not been previously analysed. The aim of this study was to estimate the herd prevalence of selected endemic bovine pathogens among large commercial dairy herds and to analyse their associations with herd culling rates and longevity.Bulk tank milk (BTM) samples and 10 heifer serum samples were collected from 120 Estonian dairy herds with at least 100 cows, between August 2019 and July 2020. All samples were tested for antibodies against bovine herpesvirus 1 (BHV-1), bovine viral diarrhoea virus (BVDV), bovine respiratory syncytial virus (BRSV), Mycoplasma bovis, Mycobacterium avium spp. paratuberculosis (MAP) and Salmonella Dublin using commercial ELISA. Data on herd size, milk yield, culling rate (CR) and mean age of the culled cows (MAofCC) were collected from the Estonian Livestock Performance Recording Ltd. The apparent herd and animal prevalences were calculated, and linear regression models were used to identify associations between the herd status of six tested pathogens and CR and MAofCC.The herd seroprevalences for antibodies based on BTM and heifer serum sample testing were BHV-1 56.7 % (95 % CI 47.3; 65.7), Mycoplasma bovis 48.3 % (95 % CI 39.1; 57.6), MAP 2.5 % (95 % CI 0.5; 7.1) and S. Dublin 24.2 % (95 % CI 16.8; 32.8) in all tested herds. Excluding vaccinated herds, herds prevalence for BVDV was 27.0 % (95 % CI 19.0; 36.3) and for BRSV 94.7 % (95 % CI 88.1; 98.3).Herd seropositive status for BRSV was associated with lower MAofCC, and herds with BSRV-seropositive youngstock had increased CR. Herds with positive BTM test results for S. Dublin culled cows at an older average age (Coef = 3.79 months, 95 % CI 0.52; 7.07, p = 0.023). MAP-positive herds had somewhat lower herd MAofCC (Coef = −6.18 months, 95 % CI −12.98; 0.63, p = 0.075). There was also a tendency of BVDV-negative herds to have a lower CR than BVDV-positive herds (Coef = −3.03 %, 95 % CI −6.54; 0.49, p = 0.090), and vaccination against BVDV tended to be protective against high CR (Coef = −6.26 %, 95 % CI −12.61; 0.09, p = 0.053 compared to infected herds).This study shows that Estonian large-scale dairy herds are endemically infected with several important cattle pathogens. Most of the studied pathogens influence longevity and culling rates, thus entailing health and economic consequences.

Clinical picture of pulmonary plague observed in the paediatric wards of antananarivo

Introduction: In Madagascar, plague is a highly contagious acute endemic infectious disease. The diagnosis of the most severe form of pneumonic plague remains difficult in children, hence the objectives of the present study; which is to identify the clinical signs of this clinical form in children and to describe its epidemiological and evolutionary profile. Methods: A retrospective case-control study was conducted in four pediatric wards in Antananarivo during the urban pneumonic plague outbreak from September 2017 to January 2018. Those cases were defined as children aged 0-15 years old suspected of having plague with positive RDT and PCR, and they were defined as children aged 0-15 years old with negative RDT and PCR. Results: Fifty-two cases of pneumonic plague were identified, half of which (50%) were under 24 months of age. A male predominance was noted with a sex ratio of 1.23 and 86.54% of the patients were from urban areas. Several clinical signs were found but none was specific for pneumonic plague: cough (59.62% p: 0.5), dyspnea (3.85% p: 0.16), chest pain (3.85% p: 0.26%), hemoptysis (7.69% p: 0.17), vomiting (9.62% p: 0.14), diarrhea (11.54% p: 0.45), altered general condition (38.46% p: 0.24%). Two deaths were noted (3.8%). Conclusion: No specific clinical warning signs have been identified in childhood pneumonic plague. In the event of an epidemic of urban pneumonic plague, any bacterial pneumonia should at least initially include active treatment against Yersinia pestis.

Multi-omics data integration and network-based analysis drives a multiplex drug repurposing approach to a shortlist of candidate drugs against COVID-19.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is undeniably the most severe global health emergency since the 1918 Influenza outbreak. Depending on its evolutionary trajectory, the virus is expected to establish itself as an endemic infectious respiratory disease exhibiting seasonal flare-ups. Therefore, despite the unprecedented rally to reach a vaccine that can offer widespread immunization, it is equally important to reach effective prevention and treatment regimens for coronavirus disease 2019 (COVID-19). Contributing to this effort, we have curated and analyzed multi-source and multi-omics publicly available data from patients, cell lines and databases in order to fuel a multiplex computational drug repurposing approach. We devised a network-based integration of multi-omic data to prioritize the most important genes related to COVID-19 and subsequently re-rank the identified candidate drugs. Our approach resulted in a highly informed integrated drug shortlist by combining structural diversity filtering along with experts’ curation and drug–target mapping on the depicted molecular pathways. In addition to the recently proposed drugs that are already generating promising results such as dexamethasone and remdesivir, our list includes inhibitors of Src tyrosine kinase (bosutinib, dasatinib, cytarabine and saracatinib), which appear to be involved in multiple COVID-19 pathophysiological mechanisms. In addition, we highlight specific immunomodulators and anti-inflammatory drugs like dactolisib and methotrexate and inhibitors of histone deacetylase like hydroquinone and vorinostat with potential beneficial effects in their mechanisms of action. Overall, this multiplex drug repurposing approach, developed and utilized herein specifically for SARS-CoV-2, can offer a rapid mapping and drug prioritization against any pathogen-related disease.

Kırım Kongo Kanamalı Ateşi Virüsü Glikoprotein Gc’yi Hedef Alan Bir DNA Aşısının Bağışıklık ve Koruyuculuk Sağlama Özelliklerinin Değerlendirilmesi

Aim: Crimean Congo Hemorrhagic Fever (CCHF) is a lethal, endemic infectious disease in human. For the preventive measures of the disease, there is currently no safe and efficient vaccine, widely for human use. Vaccine development for CCHF virus is an actively researched subject. In this study, we aimed to investigate the immunizing and protective potentials of the CCHF virus surface glycoprotein Gc that is delivered as a single antigen via a DNA based vaccine vector. Material and Methods: A DNA based vaccine targeting the immunogenic envelope glycoprotein Gc of a CCHF virus isolate with Turkey origin (Ank2) was generated and its immunogenicity and protective capability against lethal challenge in IFNα/βR-/- receptor knock out mice was assessed. Results: The developed vaccine candidate (pGc) elicited a considerable amount of neutralizing antibody responses in the vaccinated mice. The vaccine candidate significantly induced both antiviral Th1 and B cell activating Th2 immune responses deduced from the cytokine production profiles in the vaccinated mice. However, despite the immune responses elicited post-immunization, the vaccine failed to confer protection against lethal CCHF virus infection. Conclusion: To the best of our knowledge, this is the first report of a DNA vaccine candidate generated against CCHF virus based on the glycoprotein Gc. The pGc vaccine candidate exhibited antigen-specific immunity in IFN/α/βR-/- mice, but was unable to produce a protection upon lethal challenge with the homologous CCHF virus. Once we comprehensively understand the immune correlates of protection, we will be more eligible to significantly improve the efficacy of vaccines.

Human, Animal and Planet Health for Complete Sustainability.

Simple SummaryAnimal breeding must be seen within sustainability that includes human health and the health of the planet (ecology), without neglecting the economic and ethical aspects. The relationship with human health is dual, since in the absence of food of animal origin there is malnutrition, but excesses increase non-communicable diseases. However, animal farming is considered a cause of serious environmental impact, as well as a cause of suffering for animals (ethics). Therefore, it is proposed to modify the diet in relation to foods of animal origin, properly reducing them in rich countries, but increasing them in poor ones. To reduce the environmental impact of the animals, they must be reduced in number, but the quantities of food needed imply an increase in productivity and efficiency. Their good health is fundamental for these last objectives: to fight infectious and parasitic diseases, but also to ensure optimal feeding and living conditions to guarantee their welfare.In order to discuss the concepts of animal health and sustainability, we must remind ourselves that ASF (animal source foods) can play a large role in human health, but that animals are assumed to have a negative role in the environment. Indeed, ASF can compromise human health, both in excess and in deficiency, so a proper amount of them is important. In addition, the environmental impact of farmed animals: land occupation, greenhouse gas (GHG) emissions, energy use and water utilization, acidification and eutrophication, must be minimized by reducing ASF consumption, as well as by increasing productivity. To achieve this, besides genetics, feeding and good management, the hygienic-sanitary and comfort conditions that ensure good health and welfare are essential. Impaired animal health can cause zoonosis and food-borne diseases and be responsible for economic and socio-economic losses (lower production-productivity and profitability) with consequential effects on the planet’s health too, and there are big differences between developing and developed countries. In the former, a prevalence of endemic infectious diseases and parasites is observed, and there is a lack of tools to restrain them; in the latter there is a decline of the above diseases, but an increase of stress-related diseases. Their reduction is equally important but requires a different strategy. In developing countries, the strategy should be to facilitate the availability of prevention and treatment means, while in developed countries it is necessary to use drugs correctly (to reduce residues, especially antimicrobials which are associated with important resistance risks to antibiotics) and improve the living conditions of animals (welfare).

Key Learnings During the Development of a Generic Data Collection Tool to Support Assessment of Freedom of Infection in Cattle Herds.

Various European Member States have implemented control or eradication programmes for endemic infectious diseases in cattle. The design of these programmes varies between countries and therefore comparison of the outputs of different control programmes is complex. Although output-based methods to estimate the confidence of freedom resulting from these programmes are under development, as yet there is no practical modeling framework applicable to a variety of infectious diseases. Therefore, a data collection tool was developed to evaluate data availability and quality and to collect actual input data required for such a modeling framework. The aim of the current paper is to present the key learnings from the process of the development of this data collection tool. The data collection tool was developed by experts from two international projects: STOC free (Surveillance Tool for Outcome-based Comparison of FREEdom from infection, www.stocfree.eu) and SOUND control (Standardizing OUtput-based surveillance to control Non-regulated Diseases of cattle in the EU, www.sound-control.eu). Initially a data collection tool was developed for assessment of freedom of bovine viral diarrhea virus in six Western European countries. This tool was then further generalized to enable inclusion of data for other cattle diseases i.e., infectious bovine rhinotracheitis and Johne's disease. Subsequently, the tool was pilot-tested by a Western and Eastern European country, discussed with animal health experts from 32 different European countries and further developed for use throughout Europe. The developed online data collection tool includes a wide range of variables that could reasonably influence confidence of freedom, including those relating to cattle demographics, risk factors for introduction and characteristics of disease control programmes. Our results highlight the fact that data requirements for different cattle diseases can be generalized and easily included in a data collection tool. However, there are large differences in data availability and comparability across European countries, presenting challenges to the development of a standardized data collection tool and modeling framework. These key learnings are important for development of any generic data collection tool for animal disease control purposes. Further, the results can facilitate development of output-based modeling frameworks that aim to calculate confidence of freedom from disease.

Predicting the Effectiveness of Endemic Infectious Disease Control Interventions: The Impact of Mass Action versus Network Model Structure.

Analyses of the effectiveness of infectious disease control interventions often rely on dynamic transmission models to simulate intervention effects. We aim to understand how the choice of network or compartmental model can influence estimates of intervention effectiveness in the short and long term for an endemic disease with susceptible and infected states in which infection, once contracted, is lifelong. We consider 4 disease models with different permutations of socially connected network versus unstructured contact (mass-action mixing) model and heterogeneous versus homogeneous disease risk. The models have susceptible and infected populations calibrated to the same long-term equilibrium disease prevalence. We consider a simple intervention with varying levels of coverage and efficacy that reduces transmission probabilities. We measure the rate of prevalence decline over the first 365 d after the intervention, long-term equilibrium prevalence, and long-term effective reproduction ratio at equilibrium. Prevalence declined up to 10% faster in homogeneous risk models than heterogeneous risk models. When the disease was not eradicated, the long-term equilibrium disease prevalence was higher in mass-action mixing models than in network models by 40% or more. This difference in long-term equilibrium prevalence between network versus mass-action mixing models was greater than that of heterogeneous versus homogeneous risk models (less than 30%); network models tended to have higher effective reproduction ratios than mass-action mixing models for given combinations of intervention coverage and efficacy. For interventions with high efficacy and coverage, mass-action mixing models could provide a sufficient estimate of effectiveness, whereas for interventions with low efficacy and coverage, or interventions in which outcomes are measured over short time horizons, predictions from network and mass-action models diverge, highlighting the importance of sensitivity analyses on model structure. • We calibrate 4 models-socially connected network versus unstructured contact (mass-action mixing) model and heterogeneous versus homogeneous disease risk-to 10% preintervention disease prevalence.• We measure the short- and long-term intervention effectiveness of all models using the rate of prevalence decline, long-term equilibrium disease prevalence, and effective reproduction ratio.• Generally, in the short term, prevalence declined faster in the homogeneous risk models than in the heterogeneous risk models.• Generally, in the long term, equilibrium disease prevalence was higher in the mass-action mixing models than in the network models, and the effective reproduction ratio was higher in network models than in the mass-action mixing models.

Co-infection of hepatitis E virus and Plasmodium falciparum malaria: A genuine risk in sub-Saharan Africa

BackgroundThere is a high prevalence of malaria and viral hepatitis in South Africa. Co-infection with Plasmodium malaria (leading to cerebral malaria) and hepatitis E virus (HEV) is a rare phenomenon.Case presentationA 33-year-old African American male with no past medical history developed altered mental status on his return from Ivory Coast. His blood tests were significant for renal and liver failure and a high Plasmodium parasite burden of 33% on the blood smear. Interestingly, he also had a positive result for hepatitis E IgM. The patient was effectively treated with aggressive hydration and intravenous (IV) artesunate.ConclusionOur report is the first to our knowledge in the cerebral malaria literature on a patient with hepatitis E co-infection. This exciting case emphasizes the importance of considering all kinds of endemic infectious diseases when evaluating sick returning travelers presenting to the emergency department.

Enhanced passive surveillance dengue infection among febrile children: Prevalence, co-infections and associated factors in Cameroon.

Dengue virus (DENV) causes a spectrum of diseases ranging from asymptomatic, mild febrile to a life-threatening illness: dengue hemorrhagic fever. The main clinical symptom of dengue is fever, similar to that of malaria. The prevalence of dengue virus infection, alone or in association with other endemic infectious diseases in children in Cameroon is unknown. The aim of this study was to determine the prevalence of dengue, malaria and HIV in children presenting with fever and associated risk factors. Dengue overall prevalence was 20.2%, Malaria cases were 52.7% and HIV cases represented 12.6%. The prevalence of dengue-HIV co-infection was 6.0% and that of Malaria-dengue co-infection was 19.5%. Triple infection prevalence was 4.3%. Dengue virus infection is present in children and HIV-Dengue or Dengue- Malaria co-infections are common. Dengue peak prevalence was between August and October. Sex and age were not associated with dengue and dengue co-infections. However, malaria as well as HIV were significantly associated with dengue (P = 0.001 and 0.028 respectively). The diagnosis of dengue and Malaria should be carried out routinely for better management of fever.

Zoonotic disease preparedness in sub-Saharan African countries

BackgroundThe emergence of high consequence pathogens such as Ebola and SARS-CoV-2, along with the continued burden of neglected diseases such as rabies, has highlighted the need for preparedness for emerging and endemic infectious diseases of zoonotic origin in sub-Saharan Africa (SSA) using a One Health approach. To identify trends in SSA preparedness, the World Health Organization (WHO) Joint External Evaluation (JEE) reports were analysed. JEEs are voluntary, collaborative processes to assess country’s capacities to prevent, detect and rapidly respond to public health risks. This report aimed to analyse the JEE zoonotic disease preparedness data as a whole and identify strengths and weaknesses.MethodsJEE zoonotic disease preparedness scores for 44 SSA countries who had completed JEEs were analysed. An overall zoonotic disease preparedness score was calculated as an average of the sum of all the SSA country zoonotic disease preparedness scores and compared to the overall mean JEE score. Zoonotic disease preparedness indicators were analysed and data were collated into regions to identify key areas of strength.ResultsThe mean ‘Zoonotic disease’ preparedness score (2.35, range 1.00–4.00) was 7% higher compared to the mean overall JEE preparedness score (2.19, range 1.55–3.30), putting ‘Zoonotic Diseases’ 5th out of 19 JEE sub-areas for preparedness. The average scores for each ‘Zoonotic Disease’ category were 2.45 for ‘Surveillance Systems’, 2.76 for ‘Veterinary Workforce’ and 1.84 for ‘Response Mechanisms’. The Southern African region scored highest across the ‘Zoonotic disease’ categories (2.87).A multisectoral priority zoonotic pathogens list is in place for 43% of SSA countries and 70% reported undertaking national surveillance on 1–5 zoonotic diseases. 70% of SSA countries reported having public health training courses in place for veterinarians and 30% had veterinarians in all districts (reported as sufficient staffing). A multisectoral action plan for zoonotic outbreaks was in place for 14% countries and 32% reported having an established inter-agency response team for zoonotic outbreaks. The zoonotic diseases that appeared most in reported country priority lists were rabies and Highly Pathogenic Avian Influenza (HPAI) (both 89%), anthrax (83%), and brucellosis (78%).ConclusionsWith ‘Zoonotic Diseases’ ranking 5th in the JEE sub-areas and a mean SSA score 7% greater than the overall mean JEE score, zoonotic disease preparedness appears to have the attention of most SSA countries. However, the considerable range suggests that some countries have more measures in place than others, which may perhaps reflect the geography and types of pathogens that commonly occur. The category ‘Response Mechanisms’ had the lowest mean score across SSA, suggesting that implementing a multisectoral action plan and response team could provide the greatest gains.

Seroprevalence and Factors Associated with Scrub Typhus Infection among Forestry Workers in National Park Offices in South Korea.

Scrub typhus is caused by the arthropod-borne bacterium Orientia tsutsugamushi and is an endemic infectious disease in the Asia-Pacific area. This study aimed to investigate the seroprevalence of scrub typhus and identify associated risk and protective factors among forestry workers, a neglected risk group for scrub typhus, in National Park Offices in South Korea. A nationwide cross-sectional serosurvey was carried out on 1945 National Park Office forestry workers (NPOFWs) in South Korea during December 2016. We visited 29 main offices and used a structured questionnaire to collect data regarding general characteristics, work activities, work hygiene-related factors, and other potential risk factors. Serum samples from NPOFWs were tested using indirect immunofluorescence assay to detect O. tsutsugamushi immunoglobulin (Ig) G and M antibodies. Of the 1945 NPOFWs, 718 (36.9%) participated in this cross-sectional study. The seroprevalence, defined as ≥1:256 for IgG and/or ≥1:16 for IgM, was 4.9% (35/718). In multivariate logistic analysis, longer duration of work in national parks (≥15 years; odds ratio (OR), 4.19; 95% confidence interval (CI), 1.71–10.28) and dry field farming (OR, 2.47; 95% CI, 1.12–5.46) were significantly associated with a higher risk of scrub typhus infection. Furthermore, the risk of scrub typhus infection was significantly lower among NPOFWs who washed working clothes daily (OR, 0.37; 95% CI, 0.18–0.75). This study indicated that scrub typhus is an important disease among NPOFWs in South Korea. Work hygiene, especially washing working clothes daily, needs to be emphasized among NPOFWs. Additionally, more precautions are required to diminish the rate of scrub typhus infection among NPOFWs who perform dry field farming.

RNA-Seq Analysis Reveals the Role of Omp16 in Brucella-Infected RAW264.7 Cells.

Brucellosis is an endemic zoonotic infectious disease in the majority of developing countries, which causes huge economic losses. As immunogenic and protective antigens at the surface of Brucella spp., outer membrane proteins (Omps) are particularly attractive for developing vaccine and could have more relevant role in host–pathogen interactions. Omp16, a homolog to peptidoglycan-associated lipoproteins (Pals), is essential for Brucella survival in vitro. At present, the functions of Omp16 have been poorly studied. Here, the gene expression profile of RAW264.7 cells infected with Brucella suis vaccine strain 2 (B. suis S2) and ΔOmp16 was analyzed by RNA-seq to investigate the cellular response immediately after Brucella entry. The RNA-sequence analysis revealed that a total of 303 genes were significantly regulated by B. suis S2 24 h post-infection. Of these, 273 differentially expressed genes (DEGs) were upregulated, and 30 DEGs were downregulated. These DEGs were mainly involved in innate immune signaling pathways, including pattern recognition receptors (PRRs), proinflammatory cytokines, and chemokines by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. In ΔOmp16-infected cells, the expression of 52 total cells genes was significantly upregulated and that of 9 total cells genes were downregulated compared to B. suis S2-infected RAW264.7 cells. The KEGG pathway analysis showed that several upregulated genes were proinflammatory cytokines and chemokines, such as interleukin (IL)-6, IL-11, IL-12β, C–C motif chemokine (CCL2), and CCL22. All together, we clearly demonstrate that ΔOmp16 can alter macrophage immune-related pathways to increase proinflammatory cytokines and chemokines, which provide insights into illuminating the Brucella pathogenic strategies.

Why genetic selection to reduce the prevalence of infectious diseases is way more promising than currently believed.

Genetic selection for improved disease resistance is an important part of strategies to combat infectious diseases in agriculture. Quantitative genetic analyses of binary disease status, however, indicate low heritability for most diseases, which restricts the rate of genetic reduction in disease prevalence. Moreover, the common liability threshold model suggests that eradication of an infectious disease via genetic selection is impossible because the observed-scale heritability goes to zero when the prevalence approaches zero. From infectious disease epidemiology, however, we know that eradication of infectious diseases is possible, both in theory and practice, because of positive feedback mechanisms leading to the phenomenon known as herd immunity. The common quantitative genetic models, however, ignore these feedback mechanisms. Here, we integrate quantitative genetic analysis of binary disease status with epidemiological models of transmission, aiming to identify the potential response to selection for reducing the prevalence of endemic infectious diseases. The results show that typical heritability values of binary disease status correspond to a very substantial genetic variation in disease susceptibility among individuals. Moreover, our results show that eradication of infectious diseases by genetic selection is possible in principle. These findings strongly disagree with predictions based on common quantitative genetic models, which ignore the positive feedback effects that occur when reducing the transmission of infectious diseases. Those feedback effects are a specific kind of Indirect Genetic Effects; they contribute substantially to the response to selection and the development of herd immunity (i.e., an effective reproduction ratio less than one).

Can COVID-19 innovations and systems help low- and middle-income countries to re-imagine healthcare delivery?

Several low- and middle-income countries (LMICs) have responded to COVID-19 much better than expected—despite little help from high-income nations. LMICs can learn from the COVID-19 experience and re-imagine healthcare delivery. Using Bangladesh and India as examples, we explain how COVID-19 investments and systems can be leveraged to fight endemic infectious diseases.

Supplemental Material for Hulst, De Jong, and Bijma, 2020

Table S1 contains mean (over 20 replicates) observed scale heritability estimates for disease status for different genetic standard deviations in susceptibility. FigureS2 contains a schematic overview of the steps used in the simulations.FileS3 contains the R-code used to simulate populations with genetic and permanent environmental variation in susceptibility.FileS4 contains the R-code used to simulate the endemic infectious disease.

Progress in the photodynamic therapy treatment of Leishmaniasis.

Leishmaniasis is a serious and endemic infectious disease that has been reported in more than 90 countries and territories. The classical treatment presents a series of problems ranging from difficulty in administration, development of resistance, and a series of side effects. Photodynamic therapy (PDT) has already shown great potential for use as a treatment for leishmaniasis that is effective and non-invasive, with very minor side effects. PDT can also be inexpensive and easy to administer. In this review, we will report the most recent developments in the field, starting with the chemical diversity of photosensitizers, highlighting important mechanistic aspects, and noting information that may assist in designing and developing new and promising photosensitizer molecules.

Salmonella Carrier State in Ostriches and Epizootological Situation in Ararat Region

Salmonella carrier state of ostriches and epizootological conditions have been studied and identified for the first time in Ararat region of the Republic of Armenia. As an endemic infectious disease, Salmonellosis has caused significant economic damage to ostrich farms. Bacteria carrying birds, caring, feeding and keeping conditions, as well as stressful situations are predisposing factors for the mentioned disease. According to the two-year epizootological investigations, under insecure conditions the indices of infection, death and lethality have made 0.2 (20 %), 0.10 (10 %), 0.53 (53 %) respectively, while the economic loss amounted to 640 000 AMD.