Subsequent Outbreaks Research Articles

MODELING THE IMPACT OF EDUCATIONAL CAMPAIGN ON THE TRANSMISSION DYNAMICS OF EBOLA

Disease awareness that informs the public about the severity and transmission pathways of infectious diseases such as Ebola is key to curtailing an outbreak. Public health education when available can limit the intensity and duration of an Ebola outbreak in any community if there is compliance. It is important that all population groups be informed about the methods in which Ebola is transmitted to control the disease when there is an outbreak. In this paper, we study the impact of public health education that leads to behavioral changes on the dynamics of Ebola spread. The model is formulated as a system of ordinary differential equations and incorporates direct transmission from infectious, hospitalized, and deceased individuals with Ebola. We establish the existence of a disease free equilibrium and an endemic equilibrium, and investigate them for local and global stability. Model predictions show that a more informed community results in fewer cases, and thus limits the impact of an Ebola outbreak. Further, the model also predicts subsequent outbreak waves within a community in the absence of complete eradication. Lastly, the model successfully captures the dynamics of the 2014–2016 West Africa Ebola outbreak and the 2018–2020 Democratic Republic of Congo Ebola outbreak.

Predicting COVID-19 Transmission to Inform the Management of Mass Events: Model-Based Approach.

BackgroundModelling COVID-19 transmission at live events and public gatherings is essential to controlling the probability of subsequent outbreaks and communicating to participants their personalized risk. Yet, despite the fast-growing body of literature on COVID-19 transmission dynamics, current risk models either neglect contextual information including vaccination rates or disease prevalence or do not attempt to quantitatively model transmission.ObjectiveThis paper attempted to bridge this gap by providing informative risk metrics for live public events, along with a measure of their uncertainty.MethodsBuilding upon existing models, our approach ties together 3 main components: (1) reliable modelling of the number of infectious cases at the time of the event, (2) evaluation of the efficiency of pre-event screening, and (3) modelling of the event’s transmission dynamics and their uncertainty using Monte Carlo simulations.ResultsWe illustrated the application of our pipeline for a concert at the Royal Albert Hall and highlighted the risk’s dependency on factors such as prevalence, mask wearing, and event duration. We demonstrate how this event held on 3 different dates (August 20, 2020; January 20, 2021; and March 20, 2021) would likely lead to transmission events that are similar to community transmission rates (0.06 vs 0.07, 2.38 vs 2.39, and 0.67 vs 0.60, respectively). However, differences between event and background transmissions substantially widened in the upper tails of the distribution of the number of infections (as denoted by their respective 99th quantiles: 1 vs 1, 19 vs 8, and 6 vs 3, respectively, for our 3 dates), further demonstrating that sole reliance on vaccination and antigen testing to gain entry would likely significantly underestimate the tail risk of the event.ConclusionsDespite the unknowns surrounding COVID-19 transmission, our estimation pipeline opens the discussion on contextualized risk assessment by combining the best tools at hand to assess the order of magnitude of the risk. Our model can be applied to any future event and is presented in a user-friendly RShiny interface. Finally, we discussed our model’s limitations as well as avenues for model evaluation and improvement.

Biomodeling for Controlling the Spread of Coronavirus 2019

Wuhan has informed an outbreak of a typical lungs infection created by the 2019 novel coronavirus (2019-nCoV) in December 2019. Infections have been consigned to other cities, along with internationally which aggressing to trigger a global epidemic. In the past four years, coronavirus infections have become the most dangerous infections since of the event of some fresh deaths caused by corona infections in Saudi Arabia. Coronavirus infections may be planted in and spread out of Saudi Arabia by inbound and outbound Umrah visitors and non-Umrah visitors. The impact of fundamental reproductive number and zoonotic strength of infectivity on susceptible, exposed and infected peoples rate was assessed using Runge–Kutta–Felhberg strategy with shooting method. In this investigation, the vulnerable people's rate is significantly climbing in the brief interval of period owing to overwhelming and mean inactive period. Our examination shows the transmissibility of coronavirus is more grounded as contrasted and the Asia continent countries respiratory confusion. Middle East Respiratory Syndrome coronavirus is already spread in creature and human pools in Ethiopia. The Severe Acute Respiratory Syndrome coronavirus-2 growth in the Saudi Arabia may have a solemn crash on genetic assortment, interspecies circulation of these infections mostly with the reference to the alteration and recombination expectation of coronaviruses. Researches of the molecular mechanisms and genetics of this infection are provided in the component can act an important part of this project to follow tactics to prevent subsequent coronavirus outbreak.

Identification of Components of the Aggregation Pheromone of the Guam Strain of Coconut Rhinoceros Beetle, Oryctes rhinoceros, and Determination of Stereochemistry

The coconut rhinoceros beetle, Oryctes rhinoceros (Linnaeus 1758) (Coleoptera: Scarabaeidae: Dynastinae) (CRB), is endemic to tropical Asia where it damages both coconut and oil palm. A new invasion by CRB occurred on Guam in 2007 and eradication attempts failed using commonly applied Oryctes rhinoceros nudivirus (OrNV) isolates. This and subsequent invasive outbreaks were found to have been caused by a previously unrecognized haplotype, CRB-G, which appeared to be tolerant to OrNV. The male-produced aggregation pheromone of the endemic, susceptible strain of O. rhinoceros (CRB-S) was previously identified as ethyl 4-methyloctanoate. Following reports from growers that commercial lures containing this compound were not attractive to CRB-G, the aim of this work was to identify the pheromone of CRB-G. Initial collections of volatiles from virgin male and female CRB-G adults from the Solomon Islands failed to show any male- or female-specific compounds as candidate pheromone components. Only after five months were significant quantities of ethyl 4-methyloctanoate and 4-methyloctanoic acid produced by males but not by females. No other male-specific compounds could be detected, in particular methyl 4-methyloctanoate, 4-methyl-1-octanol, or 4-methyl-1-octyl acetate, compounds identified in volatiles from some other species of Oryctes. Ethyl 4-methyloctanoate elicited a strong electroantennogram response from both male and female CRB-G, but these other compounds, including 4-methyloctanoic acid, did not. The enantiomers of ethyl 4-methyloctanoate and 4-methyloctanoic acid were conveniently prepared by enzymatic resolution of the commercially-available acid, and the enantiomers of the acid, but not the ester, could be separated by gas chromatography on an enantioselective cyclodextrin phase. Using this approach, both ethyl 4-methyloctanoate and 4-methyloctanoic acid produced by male CRB-G were shown to be exclusively the (R)-enantiomers whereas previous reports had suggested male O. rhinoceros produced the (S)-enantiomers. However, re-examination of the ester and acid produced by male CRB-S from Papua New Guinea showed that these were also the (R)-enantiomers. In field trapping experiments carried out in the Solomon Islands, both racemic and ethyl (R)-4-methyloctanoate were highly attractive to both male and female CRB-G beetles. The (S)-enantiomer and the corresponding acids were only weakly attractive. The addition of racemic 4-methyloctanoic acid to ethyl 4-methyloctanoate did significantly increase attractiveness, but the addition of (R)- or (S)-4-methyloctanoic acid to the corresponding ethyl esters did not. Possible reasons for the difference in assignment of configuration of the components of the CRB pheromone are discussed along with the practical implications of these results.

Population-based analysis of the epidemiological features of COVID-19 epidemics in Victoria, Australia, January 2020 – March 2021, and their suppression through comprehensive control strategies

BackgroundVictoria experienced the greatest burden of COVID-19 in Australia in 2020. This report describes key epidemiological characteristics and corresponding control measures between 17 January 2020 and 26 March 2021. MethodsCOVID-19 notifications made to the State Government Department of Health were used in this analysis. Epidemiological features are described over 4 phases, including enhancements to testing, contact tracing and public health interventions. Demographic and clinical features of cases are described. FindingsVictoria recorded 20,483 cases of COVID-19, of which 1073 (5•2%) were acquired overseas and 19,360 (95%) were locally acquired. The initial epidemic (Phase I) was well-contained through public health interventions and was followed by relaxation of restrictions and low-level community transmission (Phase II). However, an outbreak in a hotel used to quarantine returned travellers led to wide-scale community transmission accounting for a majority (91%) of cases (Phase III). Outbreaks occurred in vulnerable settings including aged care and hospitals, contributing to high hospitalisation (12%) and case fatality rates (3•7%). Aggressive restrictions ultimately led to local elimination, and subsequent outbreaks have been swiftly managed with improved processes (Phase IV). The demographic composition of cases evolved across phases from an older, wealthier population to a less advantaged younger population, with many from culturally and linguistically diverse backgrounds. InterpretationOver time, adaptations to the public health response have strengthened capacity to respond to new cases and outbreaks in a more effective manner. The Victorian experience underscores the importance of authentic engagement with diverse communities and balancing restrictions with livelihoods.Funding: None

Nipah Virus Disease: Recent Perspective and One Health Approach.

Background:Nipah virus (NiV) first emerged in 1998 in Malaysia, causing an outbreak of respiratory illness and encephalitis in pigs. Pig-to-human transmission of NiV associated with severe febrile encephalitis was described, and it was thought to occur through close contact with infected animals. The first outbreak was reported in India in Siliguri, West Bengal in 2001 followed by Nadia, West Bengal and adjoining areas of Bangladesh in 2007, where an intermediate animal host was not identified, suggesting bat-to-human and human-to-human transmissions. Although it is extremely difficult to document the spillover event and ascertain crossing of trans-natural boundaries by bats and bringing new viruses in an unexposed population, efforts for source identification are important to understand the epidemiology of disease. As the disease transcends beyond one species and has shown to infect humans, it therefore requires the ‘One Health approach’ in which multiple sectors coordinate and work together to achieve better public health outcomes.Objective:We summarize the re-emergence and response of the Nipah virus outbreaks (NiVD) in Kerala, India, about 1800 kms away, a decade later in 2018 and 2019. The paper recapitulates involvement of various stakeholders from the Ministry of Health and Family Welfare, Directorate of Health Research, Indian Council of Agricultural Research, State Health Department, State Animal Husbandry, District Administration, and multidisciplinary response mechanism during the NiVD outbreaks of 2018 and 2019.Methods:Information was collected from the Press Information Bureau (PIB), media/weekly alerts from the Integrated Disease Surveillance Programme (IDSP), news articles from print and electronic media, newsletters, advisories from the National Centre for Disease Control (NCDC), Disease Outbreak News (DON), World Health Organization (WHO), and published papers from various stakeholders.Findings & Conclusion:The evidence of NiV in humans and bats, with samples collected from the outbreak sites, was laboratory confirmed. The multidisciplinary response mechanisms during the 2018 outbreak helped in further understanding the importance of the One Health approach for systemic and streamlined response utilizing existing surveillance systems. This was of utmost help in the subsequent outbreak of the disease that occurred during 2019, wherein there was no documented spread of disease from the index case and no mortality was observed. This success reiterates the need for institutionalizing the involvement and cooperation of various departments and organizations during public health emergencies, especially of Zoonotic diseases, using the One Health approach.

Molecular epidemiologic characteristics of hemagglutinin from five waves of avian influenza A (H7N9) virus infection, from 2013 to 2017, in Zhejiang Province, China

There have been five waves of influenza A (H7N9) epidemics in Zhejiang Province between 2013 and 2017. Although the epidemiological characteristics of the five waves have been reported, the molecular genetics aspects, including the phylogeny, evolution, and mutation of hemagglutinin (HA), have not been systematically investigated. A total of 154 H7N9 samples from Zhejiang Province were collected between 2013 and 2017 and sequenced using an Ion Torrent Personal Genome Machine. The starting dates of the waves were 16 March 2013, 1 July 2013, 1 July 2014, 1 July 2015, and 1 July 2016. Single-nucleotide polymorphisms (SNPs) and amino acid mutations were counted after the HA sequences were aligned. The evolution of H7N9 matched the temporal order of the five waves, among which wave 3 played an important role. The 55 SNPs and 14 amino acid mutations with high frequency identified among the five waves revealed the dynamic occurrence of mutation in the process of viral dissemination. Wave 3 contributed greatly to the subsequent epidemic of waves 4 and 5 of H7N9. Compared with wave 1, wave 5 was characterized by more mutations, including A143V and R148K, two mutations that have been reported to weaken the immune response. In addition, some amino acid mutations were observed in wave 5 that led to more lineages. It is necessary to strengthen the surveillance of subsequent H7N9 influenza outbreaks.

Genetic and phylogenetic analysis of lumpy skin disease viruses (LSDV) isolated from the first and subsequent field outbreaks in India during 2019 reveals close proximity with unique signatures of historical Kenyan NI-2490/Kenya/KSGP-like field strains.

Lumpy skin disease (LSD), an economically important viral disease of cattle caused by lumpy skin disease virus (LSDV) has recently spread into South and East Asia. LSD emerged in India in August 2019, first in Odisha State and spread to other areas, but there is scanty data on source and molecular epidemiology of LSDV involved in the initial outbreaks. Here we report genetic relationships and molecular features of LSDV, causing outbreaks in cattle spanning seven districts in Odisha and West Bengal States during August-December, 2019. Twelve LSDV isolates obtained using lamb testis cells were sequenced and analysed in four complete genes, GPCR, RPO30, P32 and EEV. The phylogenetic analysis revealed that all the Indian LSDV isolates from 2019 outbreaks are very closely related (99.7%-100%) to the historical Kenyan NI-2490/Kenya/KSGP-like field strains. Importantly, our results demonstrated that LSDV strains involved in 2019 outbreaks in India and Bangladesh are very similar in GPCR (99.7%), RPO30 (100%) and partial EEV (100%) sequences, indicating a common exotic source of LSDV introduction. Additionally, a 12-nucleotide insertion was found in GPCR gene of LSDV strains from 2019 outbreaks in India and Bangladesh. The findings of this study highlight the importance of continuous monitoring and molecular characterization of LSDV strains. These data should be useful while developing diagnostic and control strategies against LSD in India.

Implementation of Food Safety Management Systems along with Other Management Tools (HAZOP, FMEA, Ishikawa, Pareto). The Case Study of Listeria monocytogenes and Correlation with Microbiological Criteria.

The food industry’s failure in planning and designing of and in implementing a Food Safety Management System and its foundation elements leads, in most instances, to compromised food safety and subsequent foodborne illness outbreaks. This phenomenon was noticed, worldwide, for all food processors, but with a much higher incidence in the medium- and small-sized food processing plants. Our study focuses on the importance of Food Safety Management System (FSMS), Critical Control Points Hazard Analysis (HACCP) and the Prerequisite Programs (PRPs) as the foundation of HACCP, in preventing foodborne outbreaks. For emphasis, we make use of the example of organizational food safety culture failures and the lack of managerial engagement which resulted in a multi-state listeriosis outbreak in USA. Moreover, we correlate this with microbiological criteria. Implementation of food safety management systems (ISO 22000:2018) along with incorporation of management tools such as HAZOP, FMEA, Ishikawa and Pareto have proved to be proactive in the maintenance of a positive food safety culture and prevention of cross-contamination and fraud.

"Mass gathering events and COVID-19 transmission in Borriana (Spain): A retrospective cohort study".

Mass gathering events (MGEs) are associated with the transmission of COVID-19. Between 6 and 10 March 2020, several MGEs related to the Falles festival took place in Borriana, a municipality in the province of Castellon (Spain). The aim of this study was to estimate the incidence of COVID-19 and its association with these MGEs, and to quantify the potential risk factors of its occurrence. During May and June 2020, a population-based retrospective cohort study was carried out by the Public Health Center of Castelló and the Hospital de la Plana in Vila-real. Participants were obtained from a representative sample of 1663 people with potential exposure at six MGEs. A questionnaire survey was carried out to obtain information about attendance at MGEs and COVID-19 disease. In addition, a serologic survey of antibodies against SARS-Cov-2 was implemented. Inverse probability weighted regression was used in the statistical analysis. A total of 1338 subjects participated in the questionnaire survey (80.5%), 997 of whom undertook the serologic survey. Five hundred and seventy cases were observed with an attack rate (AR) of 42.6%; average age was 36 years, 62.3% were female, 536 cases were confirmed by laboratory tests, and 514 cases were found with SARS-CoV-2 total antibodies. Considering MGE exposure, AR was 39.2% (496/1264). A dose-response relationship was found between MGE attendance and the disease, (adjusted relative risk [aRR] = 4.11 95% confidence interval [CI]3.25-5.19). Two MGEs with a dinner and dance in the same building had higher risks. Associated risk factors with the incidence were older age, obesity, and upper and middle class versus lower class; current smoking was protective. The study suggests the significance of MGEs in the COVID-19 transmission that could explain the subsequent outbreak in Borriana.

Review of Vesicular Stomatitis in the United States with Focus on 2019 and 2020 Outbreaks.

Vesicular stomatitis (VS) is a vector-borne livestock disease caused by vesicular stomatitis New Jersey virus (VSNJV) or vesicular stomatitis Indiana virus (VSIV). The disease circulates endemically in northern South America, Central America, and Mexico and only occasionally causes outbreaks in the United States. Over the past 20 years, VSNJV outbreaks in the southwestern and Rocky Mountain regions occurred with incursion years followed by virus overwintering and subsequent expansion outbreak years. Regulatory response by animal health officials is deployed to prevent spread from lesioned animals. The 2019 VS incursion was the largest in 40 years, lasting from June to December 2019 with 1144 VS-affected premises in 111 counties in eight states (Colorado, Kansas, Nebraska, New Mexico, Oklahoma, Texas, Utah, and Wyoming) and was VSIV serotype, last isolated in 1998. A subsequent expansion occurred from April to October 2020 with 326 VS-affected premises in 70 counties in eight states (Arizona, Arkansas, Kansas, Missouri, Nebraska, New Mexico, Oklahoma, and Texas). The primary serotype in 2020 was VSIV, but a separate incursion of VSNJV occurred in south Texas. Summary characteristics of the outbreaks are presented along with VSV-vector sampling results and phylogenetic analysis of VSIV isolates providing evidence of virus overwintering.

Insights gained from early modelling of COVID-19 to inform the management of outbreaks in UK prisons

PurposeIn this work, the authors present some of the key results found during early efforts to model the COVID-19 outbreak inside a UK prison. In particular, this study describes outputs from an idealised disease model that simulates the dynamics of a COVID-19 outbreak in a prison setting when varying levels of social interventions are in place, and a Monte Carlo-based model that assesses the reduction in risk of case importation, resulting from a process that requires incoming prisoners to undergo a period of self-isolation prior to admission into the general prison population.Design/methodology/approachPrisons, typically containing large populations confined in a small space with high degrees of mixing, have long been known to be especially susceptible to disease outbreaks. In an attempt to meet rising pressures from the emerging COVID-19 situation in early 2020, modellers for Public Health England’s Joint Modelling Cell were asked to produce some rapid response work that sought to inform the approaches that Her Majesty’s Prison and Probation Service (HMPPS) might take to reduce the risk of case importation and sustained transmission in prison environments.FindingsKey results show that deploying social interventions has the potential to considerably reduce the total number of infections, while such actions could also reduce the probability that an initial infection will propagate into a prison-wide outbreak. For example, modelling showed that a 50% reduction in the risk of transmission (compared to an unmitigated outbreak) could deliver a 98% decrease in total number of cases, while this reduction could also result in 86.8% of outbreaks subsiding before more than five persons have become infected. Furthermore, this study also found that requiring new arrivals to self-isolate for 10 and 14 days prior to admission could detect up to 98% and 99% of incoming infections, respectively.Research limitations/implicationsIn this paper we have presented models which allow for the studying of COVID-19 in a prison scenario, while also allowing for the assessment of proposed social interventions. By publishing these works, the authors hope these methods might aid in the management of prisoners across additional scenarios and even during subsequent disease outbreaks. Such methods as described may also be readily applied use in other closed community settings.Originality/valueThese works went towards informing HMPPS on the impacts that the described strategies might have during COVID-19 outbreaks inside UK prisons. The works described herein are readily amendable to the study of a range of addition outbreak scenarios. There is also room for these methods to be further developed and built upon which the timeliness of the original project did not permit.

Indirect Effect of Pesticides on Insects and Other Arthropods.

Pesticides released to the environment can indirectly affect target and non-target species in ways that are often contrary to their intended use. Such indirect effects are mediated through direct impacts on other species or the physical environment and depend on ecological mechanisms and species interactions. Typical mechanisms are the release of herbivores from predation and release from competition among species with similar niches. Application of insecticides to agriculture often results in subsequent pest outbreaks due to the elimination of natural enemies. The loss of floristic diversity and food resources that result from herbicide applications can reduce populations of pollinators and natural enemies of crop pests. In aquatic ecosystems, insecticides and fungicides often induce algae blooms as the chemicals reduce grazing by zooplankton and benthic herbivores. Increases in periphyton biomass typically result in the replacement of arthropods with more tolerant species such as snails, worms and tadpoles. Fungicides and systemic insecticides also reduce nutrient recycling by impairing the ability of detritivorous arthropods. Residues of herbicides can reduce the biomass of macrophytes in ponds and wetlands, indirectly affecting the protection and breeding of predatory insects in that environment. The direct impacts of pesticides in the environment are therefore either amplified or compensated by their indirect effects.

How will mass-vaccination change COVID-19 lockdown requirements in Australia?

BackgroundTo prevent future outbreaks of COVID-19, Australia is pursuing a mass-vaccination approach in which a targeted group of the population comprising healthcare workers, aged-care residents and other individuals at increased risk of exposure will receive a highly effective priority vaccine. The rest of the population will instead have access to a less effective vaccine.MethodsWe apply a large-scale agent-based model of COVID-19 in Australia to investigate the possible implications of this hybrid approach to mass-vaccination. The model is calibrated to recent epidemiological and demographic data available in Australia, and accounts for several components of vaccine efficacy.FindingsWithin a feasible range of vaccine efficacy values, our model supports the assertion that complete herd immunity due to vaccination is not likely in the Australian context. For realistic scenarios in which herd immunity is not achieved, we simulate the effects of mass-vaccination on epidemic growth rate, and investigate the requirements of lockdown measures applied to curb subsequent outbreaks. In our simulations, Australia’s vaccination strategy can feasibly reduce required lockdown intensity and initial epidemic growth rate by 43% and 52%, respectively. The severity of epidemics, as measured by the peak number of daily new cases, decreases by up to two orders of magnitude under plausible mass-vaccination and lockdown strategies.InterpretationThe study presents a strong argument for a large-scale vaccination campaign in Australia, which would substantially reduce both the intensity of future outbreaks and the stringency of non-pharmaceutical interventions required for their suppression.FundingAustralian Research Council; National Health and Medical Research Council.

B-PO01-089 SUDDEN CARDIAC ARREST DURING THE COVID-19 PANDEMIC: SIGNIFICANT EFFECTS ON INCIDENCE AND OUTCOMES

Recent reports suggest that higher COVID-19 incidence may be associated with higher out-of-hospital sudden cardiac arrest (SCA) burden and worse outcomes. To compare SCA incidence and outcomes during the COVID-19 pandemic (March 1 - Dec 31, 2020) to the corresponding period in 2019 in a US community. All out of hospital SCA cases with likely cardiac etiology attended by emergency medical services (EMS) were prospectively identified during the COVID-19 pandemic period in Ventura County, CA (pop. 848,112). We compared SCA incidence, resuscitation variables (Utstein elements) and outcomes in 2020 to 2019. COVID monthly counts were obtained from US Centers for Disease Control data. In 2019 there were 314 SCA cases in Ventura County (average 31.4 per month), corresponding to a 10-month incidence of 36.9 per 100,000. In 2020 there were 410 SCA cases (41.0 per month; 30% higher than 2019 average), for a 10-month incidence of 48.2 per 100,000 (p<0.001). A spike in both COVID and SCA incidence was observed in December 2020 (Figure). The proportion of SCAs with shockable rhythm also declined (25% to 19%, p=0.05), as did survival to hospital discharge (14.7% to 8.8%, p=0.01). There were no significant differences in the percent with witnessed arrest (48% to 43%, p=0.20), bystander CPR (54% to 48%, p=0.10), and return of spontaneous circulation (33% to 28%, p=0.15). SCA incidence was significantly higher and survival outcomes lower during the COVID-19 pandemic period, with evidence of overlap between the two conditions. These findings have implications for community public health and EMS response planning during the pandemic and subsequent outbreaks.

Quantification of SARS-CoV-2 spike and nucleocapsid proteins using isotope dilution tandem mass spectrometry

The emergence and subsequent global outbreak of the novel coronavirus SARS-CoV-2 prompted our laboratory to launch efforts to develop methods for SARS-CoV-2 antigen detection and quantification. We present an isotope dilution mass spectrometry method (IDMS) for rapid and accurate quantification of the primary antigens, spike and nucleocapsid proteins. This IDMS method utilizes liquid chromatography-tandem mass spectrometry (LC-MS/MS) to analyze sample tryptic digests for detection and quantification of selected conserved peptides of SARS-CoV-2 spike and nucleocapsid proteins. The IDMS method has the necessary attributes to be successfully utilized for accurate quantification in SARS-CoV-2 protein-based vaccines and as targets of rapid diagnostic tests. Absolute quantification was achieved by quantifying and averaging 5 peptides for spike protein (3 peptides in the S1 subunit and 2 peptides in the S2 subunit) and 4 peptides for nucleocapsid protein. The overall relative standard deviation of the method was 3.67% for spike protein and 5.11% for nucleocapsid protein. IDMS offers speed (5 h total analysis time), sensitivity (LOQ; 10 fmol/µL) and precision for quantification of SARS-CoV-2 spike and nucleocapsid proteins.

Iranian-American Tensions and the Energy Security of the Persian Gulf Countries

ABSTRACT At the end of April 2020, Iran and the United States again exchanged harsh statements regarding each other’s naval operations in the Persian Gulf and threatened to use force against each other. While there was nothing new in the exchange of threats, two aspects are cause for concern. First, the exchange of statements came after a pause that lasted several months following the assassination by the American military of Qosem. Soleimani, a high-ranking officer in the Islamic Revolutionary Guard Corps, in January 2020. The sharp escalation at the time forced Tehran to be more cautious in its statements and actions, and the subsequent outbreak of the COVID-19 epidemic completely distracted the two sides from continuing the conflict. Their return to aggressive rhetoric suggests that the United States and Iran have adjusted to the new conditions and are ready to continue their traditional game of “chicken.” Second, the Iranian–American tensions flared at a particularly unfavorable moment. This flare-up will inevitably heighten the apprehensions of consumers of oil from the Persian Gulf region regarding potential threats to the security of raw-material supplies. The escalation, however, will not primarily harm the interests of consumers, as was the case in previous decades (from the 1970s to the 2000s), when the very presence of a threat to oil exports from the region’s countries led to oil price increases. This time the main victims will be the regional producers, who could lose their traditional customers. This reflects both a result of the current evolution of the world oil market, in which the rules of the game are no longer set by the producers of oil but by its consumers, and a shift of emphasis in the safeguarding of the Gulf states’ energy security.

Susceptible-Infected-Recovered model study using free particle dynamics

A study on the epidemiologic Susceptible-Infected-Recovered (SIR) model is presented using free particle dynamics. The study is performed using a computational model consisting of randomly allocated particles in a closed domain which are free to move inrandom directions with the ability to collide into each other. The transmission rules for the particle–particle interactions are based on the main viral infection mechanisms, resulting in real–time results of the number of susceptible, infected, and recovered particles within a population of N= 200 particles. The results are qualitatively compared with a differential equation SIR model in terms of the transmission rate β, recovery rate γ, and the basic reproductive number R0, yielding overall good results. The effect of the particle density ρ on R0 is also studied to analyze how an infectious disease spreads over different types of populations. The versatility of the proposed free–particle–dynamics SIR model allows to simulate different scenarios, such as social distancing, commonly referredto as quarantine, no social distancing measures, and a mixture of the former and the latter. It is found that by implementing early relaxation of social distancing measures before the number of infected particles reaches zero, could lead to subsequent outbreaks such as the particular events observed in different countries due to the ongoing COVID–19 health crisis

Prediction of changing predator–prey interactions under warming: A simulation study using two aphid–ladybird systems

AbstractPredator–prey interactions are key factors for understanding ecosystem structure and function. Global warming alters the dynamics and stability of predator and prey populations in the long term. Extreme temperatures can also lead to short‐term population outbreaks and collapses. Thus, it is necessary to consider time scales when predicting warming effects on predator–prey interactions. Two aphid–ladybird systems, Myzus persicae–Coccinella septempunctata (M‐C) and Aphis gossypii–C. septempunctata (A‐C), were investigated. Using a temperature‐dependent predator–prey model, the short‐ (SIS, daily interactions) and long‐term interaction strength (LIS, interactions after reaching a persistent state) were quantified under different temperatures based on a dynamic index. SIS and LIS increased with temperature, but the patterns and magnitudes of the two systems differed. SIS increased linearly and exponentially in the A‐C and M‐C system, respectively. However, the SISs in the A‐C system were stronger than those in the M‐C system under most temperature ranges. LIS increased linearly with temperature in both systems; its values in the M‐C system were always larger than those in the A‐C system. The abruptly increasing SIS in the M‐C system caused population collapse, which was the main reason for the magnitude reversal between the SISs and LISs of the two systems. The A‐C system did not collapse, but a decoupled SIS and subsequent aphid outbreak were temporarily observed under extreme temperatures. Understanding how time scales influence interaction strengths may be critical to predicting population stability and fluctuations in ecosystems.

Abstract 047: Using Geospatial Data To Eliminate Disparities In Covid-19 Testing

Introduction: The first case of COVID-19 in Chattanooga/Hamilton County, Tennessee (CHC) was identified on March 13, 2020. By early April, 51 RT-PCR confirmed cases were identified, with white, non-Hispanic males and females representing 82% (41/51) of positive cases and remaining cases representing black residents (18%; 9/51). That few people from racial/ethnic minorities were being tested became a key public health concern. We hypothesized that local mapping of health-related data would identify regions where individuals at greater risk for COVID-19 live and work and have limited access to testing and healthcare services. Methods: The CDC 500 Cities data was used to generate layered maps of prevalence estimates for cardiovascular disease, type 2 diabetes mellitus, chronic lung disease, and the behavioral risk factors of physical inactivity and obesity. Layers also included the CDC Social Vulnerability Index, age distribution, gender, race, ethnicity, and zip codes. Maps were shared with intersectoral collaborators representing the black and Hispanic/Latinx communities who provided specific neighborhood information to the maps. Collaborators included hospital systems, the local health department, community health centers, the private sector, and non-profit organizations. Maps were used to identify geographic sites for mobile and strategic testing within communities at higher risk for the spread of the coronavirus. Specific diverse neighborhoods along with worksites were then provided with testing beginning in early May and ongoing. Results: Strategic and mobile testing beginning in early May increased three-fold the number of identified new cases of COVID-19. Seventy percent (652/932) of these positive tests were among ethnically Hispanic/Latinx and 16% (149/932) among black residents. Positive tests continued to increase at a greater rate among Hispanic/Latinx and black residents compared with white residents through the months of May-July (68/10K vs. 2.6/10K, OR = 4.85, 95% CI 2.66, 9.02). Conclusions: This example of inter-sectoral collaboration, data sharing, and data use through strategic mapping of vulnerable populations for COVID-19 was an effective means to enhance COVID-19 testing and identification of positive cases throughout CHC. This expanded partnering resulting in targeted testing may be a useful approach among similar communities and subsequent outbreaks.