scholarly journals Qualitative and Quantitative Analyses of COVID-19 Dynamics

Axioms ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 210
Author(s):  
Taye Samuel Faniran ◽  
Leontine Nkague Nkamba ◽  
Thomas Timothee Manga
Keyword(s):  
High Risk ◽  
General Public ◽  
Deterministic Model ◽  
Negative Impact ◽  
Positive Impact ◽  
Transmission Rate ◽  
Low Risk ◽  
Contact Tracing ◽  
Epidemic Curve ◽  
Underlying Diseases

COVID-19 is a highly contagious disease which has spread across the world. A deterministic model that considers an important component of individuals with vertically transmitted underlying diseases (high-risk susceptible individuals), rather than the general public, is formulated in this paper. We also consider key parameters that are concerned with the disease. An epidemiological threshold, R0, is computed using next-generation matrix approach. This is used to establish the existence and global stability of equilibria. We identify the most sensitive parameters which effectively contribute to change the disease dynamics with the help of sensitivity analysis. Our results reveal that increasing contact tracing of the exposed individuals who are tested for COVID-19 and hospitalizing them, largely has a negative impact on R0. Results further reveal that transmission rate between low-risk/high-risk susceptible individuals and symptomatic infectious individuals β and incubation rate of the exposed individuals σ have positive impact on R0. Numerical simulations show that there are fewer high-risk susceptible individuals than the general public when R0<1. This may be due to the fact that high-risk susceptible individuals may prove a bit more difficult to control than the low-risk susceptible individuals as a result of inherited underlying diseases present in them. We thus conclude that high level of tracing and hospitalizing the exposed individuals, as well as adherence to standard precautions and wearing appropriate Personal Protective Equipment (PPE) while handling emergency cases, are needed to flatten the epidemic curve.

scholarly journals Pilot evaluation of risk assessment and enhanced protocols regarding contacts at an international professional golf event

2021 ◽  
Vol 7 (3) ◽  
pp. e001127
Author(s):  
Patrick G Robinson ◽  
Andrew Murray ◽  
Volker Sheer ◽  
Graeme Close ◽  
Denis F Kinane
Keyword(s):  
Risk Assessment ◽  
Pilot Study ◽  
High Risk ◽  
Disease Transmission ◽  
Low Risk ◽  
Contact Tracing ◽  
Sporting Events ◽  
Medical Surveillance ◽  
Rt Pcr ◽  
Antigen Testing

ObjectivesThe aim of this study was to assess whether a risk assessment and managed risk approach to contact tracing was practical and feasible at the Gran Canaria Lopesan Open 2021 and could inform further pilot work regarding disease transmission during elite sporting events.MethodsThis prospective cohort study included all international attendees. All participants required a minimum of one negative reverse transcriptase PCR (RT-PCR) test prior to travelling to each tournament. High-risk contacts were isolated for 10 days. Moderate-risk contacts received education regarding enhanced medical surveillance, had daily rapid antigen testing for 5 days, with RT-PCR day 5, mandated mask use and access to outside space for work purposes only. Low-risk contacts received rapid antigen testing every 48 hours and PCR testing on day 5.ResultsA total of 550 persons were accredited and were required to undergo RT-PCR testing before the event. Two of these tests were positive (0.36%). Of these, case 1 had 1 high, 23 moderate and 48 low-risk contacts. Case 2 did not have any significant travel history within 2 days of positive test and had one high-risk contact. There were no further positive tests on site in the wider cohort of attendees, from a total of 872 RT-PCR and 198 rapid antigen tests.ConclusionsThis pilot study showed it is practical, feasible and well accepted to provide enhanced (daily) virus testing and risk-mitigating measures at a professional golf event. Further study is required to assess the efficacy of these interventions; however, no transmission was found in this pilot study.

scholarly journals A comparison of COVID-19 secondary attack rate in household and close contacts compared to current risk stratification guidelines of the Kerala government

2021 ◽  
pp. 004947552110020
Author(s):  
Balram Rathish ◽  
Arun Wilson ◽  
Sonya Joy
Keyword(s):  
High Risk ◽  
Risk Stratification ◽  
Attack Rate ◽  
Low Risk ◽  
Contact Tracing ◽  
Index Cases ◽  
Current Risk ◽  
Close Contacts

COVID-19 has been found to be highly infectious with a high secondary attack rate with a R0 of 3.3. However, the secondary attack rate based on risk stratification is sparsely reported, if ever. We studied the contact tracing data for two index cases of COVID-19 with some overlap of contacts. We found that 60% of high-risk contacts and 0% of low-risk contacts of symptomatic COVID-19 patients contracted the infection, in keeping with the Kerala government contact risk stratification guidelines.

scholarly journals The Moderation of Human Characteristics in the Control Mechanisms of Rumours in Social Media: The Case of Food Rumours in China

2022 ◽  
Vol 12 ◽  
Author(s):  
Sangluo Sun ◽  
Xiaowei Ge ◽  
Xiaowei Wen ◽  
Fernando Barrio ◽  
Ying Zhu ◽  
...  
Keyword(s):  
General Public ◽  
Negative Impact ◽  
Positive Impact ◽  
Control Process ◽  
Control Mechanisms ◽  
Analysis Model ◽  
Long Run ◽  
The Government ◽  
Positive Comment ◽  
The Relationship

Social networks are widely used as a fast and ubiquitous information-sharing medium. The mass spread of food rumours has seriously invaded public’s healthy life and impacted food production. It can be argued that the government, companies, and the media have the responsibility to send true anti-rumour messages to reduce panic, and the risks involved in different forms of communication to the public have not been properly assessed. The manuscript develops an empirical analysis model from 683 food anti-rumour cases and 7,967 data of the users with top comments to test the influence of the strength of rumour/anti-rumour on rumour control. Furthermore, dividing the users into three categories, Leaders, Chatters, and General Public, and study the influence of human characteristics on the relationship between the strength of rumour/anti-rumour and rumour control by considering the different human characteristics as moderator variables. The results showed that anti-rumours have a significant positive impact on the control of rumours; the ambiguity of rumours has a significant negative impact on the Positive Comment Index (PCI) in rumour control. Further, the Leaders increased the overall level of PCI, but negatively adjusted the relationship between evidence and PCI; the Chatters and the General Public reduced the overall level of PCI, and Chatters weakened the relationship between the specific type of anti-rumour form and PCI while the General Public enhanced the relationship between the specific type of anti-rumour form and PCI. In the long run, the role of Leaders needs to be further improved, and the importance of the General Public is growing in the food rumour control process.

scholarly journals Out-Patient Attitude towards Hospitals during COVID-19 in India

2022 ◽  
Vol 40 (S1) ◽  
Author(s):  
SIJI OLIVER ◽  
C. L. JEBA MELVIN
Keyword(s):  
High Risk ◽  
Medical Consultation ◽  
Low Risk ◽  
Healthcare Sector ◽  
Healthcare Industry ◽  
New Normal ◽  
Physician Visits ◽  
Patient Attitude ◽  
The Face ◽  
Underlying Diseases

COVID-19, one of the worst pandemics in recent years, have changed the face of our world. Every sector has been experiencing a tug in unexpected directions than anticipated. Often it is said that the healthcare sector is facing a boom in this COVID-19 episode, nevertheless there has been a decline of out-patient segment in hospitals. An out-patient is one who visits a hospital for treatment without staying overnight. Through this time of uncertainty where a new normal is being  burgeoned, the people’s attitude towards healthcare has shifted a great deal. Predominantly out-patients are hesitant to continue with their regular physician visits by delaying or avoiding unneeded visits. People with underlying diseases, both which are at low risk or at high risk, find themselves at higher caution due to the COVID-19. This study focuses to understand the attitude of out-patients and of out-patient’s with risk during this COVID-19 pandemic towards hospitals in India. Online or Tele medical consultation has picked up momentum among out-patients during the COVID-19 Unlock phase which shines a possibility as a new normal in the healthcare industry.

scholarly journals Mathematical modelling of COVID-19 vaccination strategies in Kyrgyzstan

2021 ◽  
Author(s):  
Ainura Moldokmatova ◽  
Aizhan Dooronbekova ◽  
Chynar Jumalieva ◽  
Aibek Mukambetov ◽  
Aisuluu Kubatova ◽  
...  
Keyword(s):  
High Risk ◽  
Deterministic Model ◽  
Risk Groups ◽  
Short Term ◽  
Epidemic Curve ◽  
Vaccination Strategies ◽  
Current Vaccine ◽  
Incidence And Mortality ◽  
High Incidence ◽  
Age Dependent

Abstract Objectives: In December 2020, an unprecedented vaccination programme to deal with the COVID-19 pandemic was initiated worldwide. However, the vaccine provision is currently insufficient for most countries to vaccinate their entire eligible population, so it is essential to develop the most efficient vaccination strategies. COVID-19 disease severity and mortality vary by age, therefore age-dependent vaccination strategies must be developed. Study design and Methods: Here, we use an age-dependent SIERS (susceptible, infected, exposed, recovered, susceptible), deterministic model, to compare four hypothetical age-dependent vaccination strategies and their potential impact on the COVID-19 epidemic in Kyrgyzstan. Results: Over the short-term (until March 2022), a vaccination rollout strategy focussed on high-risk groups (aged greater than 50 years) with some vaccination among high-incidence groups (aged 20 to 49 years) may decrease symptomatic cases and COVID-19-attributable deaths. However, there will be limited impact on the estimated overall number of COVID19 cases with the relatively low coverage of high incidence groups (15 to 25% based on current vaccine availability). Vaccination plus nonpharmaceutical interventions (NPIs), such as mask-wearing and social distancing will further decrease COVID-19 incidence and mortality and may have an indirect impact on all-cause mortality. Conclusions: Our results and other evidence suggest that vaccination is most effective in flattening the epidemic curve and reducing mortality if supported by NPIs. In the short term, focussing on high-risk groups may reduce the burden on the health system and result in fewer deaths. However, the herd effect from delaying another peak may only be achieved by greater vaccination coverage in high incidence groups.

scholarly journals LB7. Contract Tracing Investigation Following First Case of Andes Virus in the United States

2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S761-S762
Author(s):  
Aaron Kofman ◽  
Paula Eggers ◽  
Anne Kjemtrup ◽  
Rebecca Hall ◽  
Shelley Brown ◽  
...  
Keyword(s):  
High Risk ◽  
Incubation Period ◽  
Close Contact ◽  
The United States ◽  
Body Fluids ◽  
Low Risk ◽  
Contact Tracing ◽  
Rt Pcr ◽  
First Case ◽  
Andes Virus

Abstract Background In January 2018, a patient admitted to a Delaware hospital tested positive for New World hantavirus by IgM and IgG ELISA. Subsequent testing by CDC’s Viral Special Pathogens Branch (VSPB) confirmed Andes virus (ANDV) by reverse transcription polymerase chain reaction (RT-PCR) and sequencing. ANDV is transmitted to humans through contact with long-tailed rice rats endemic to Argentina and Chile. Unlike other hantavirus species, ANDV can be transmitted person to person, but transmission is typically limited to close contacts of ill persons. Because of this risk, a contact tracing investigation was initiated by CDC, state and county health departments. Method A suspect case was defined as a person with close contact with the traveler who became ill within the maximum incubation period (42 days) following last contact. A high-risk contact was defined as a person with exposure to the traveler’s body fluids. A low-risk contact was defined as a person who had provided care or in-flight service to, or was seated near the traveler for at least 1 hour, in the absence of exposure to body fluids. All contacts were advised to self-monitor their temperature daily for 42 days from last contact, and to seek medical care for any of the specified symptoms. Contacts that developed symptoms were tested for ANDV by RT-PCR and serology by VSPB. Result Fifty-three contacts were identified in six states; 51 were successfully reached. Of these, 28 were healthcare workers, 15 were airline contacts, seven were acquaintances of the traveler, and one was a hospital roommate. Two high-risk contacts were identified, both of whom remained asymptomatic. Six low-risk contacts reported influenza-like illness, diarrhea, or mild rhinitis during the incubation period. All six symptomatic low-risk contacts tested negative for ANDV by PCR, IgM, and IgG. The remaining low-risk contacts remained asymptomatic. Conclusion Hospitalized patients with ANDV should be managed with standard, contact, and droplet precautions. While the risk of human-to-human transmission is low, contact tracing should be considered to identify potential cases and limit additional exposures. Health providers should consider ANDV in returning travelers with a nonspecific febrile or acute respiratory illness who have traveled to the Andes region of Argentina or Chile in the preceding 6 weeks. Disclosures All authors: No reported disclosures.

Hospital based contact tracing of COVID-19 patients and health care workers during the COVID-19 Pandemic in Eastern India (Preprint)

2021 ◽  
Author(s):  
Durgesh Prasad Sahoo ◽  
Arvind Kumar Singh ◽  
Dinesh Prasad Sahu ◽  
Somen Kumar Pradhan ◽  
Binod Kumar Patro ◽  
...  
Keyword(s):  
Health Care ◽  
High Risk ◽  
Risk Stratification ◽  
Health Care Workers ◽  
Control Strategies ◽  
Routine Data ◽  
Low Risk ◽  
Contact Tracing ◽  
P Value ◽  
Care Workers

BACKGROUND Contact tracing and subsequent quarantining of Health Care Workers (HCWs) is essential to minimize further transmission of SARS-CoV2 infection. OBJECTIVE In this study, we have reported the yield of contact tracing of COVID-19 cases and risk stratification of HCWs exposed to them. METHODS This is an analysis of routine data collected for contact tracing of COVID-19 cases from 19th March to 31st August 2020 at All India Institute of Medical Sciences, Bhubaneswar, Odisha, India. COVID-19 cases were either admitted patients, out-patients, or HCWs in the hospital. HCWs who were exposed to COVID-19 cases were categorized as per the risk stratification guidelines into high-risk contacts and low-risk contacts RESULTS During contact tracing, 3411 HCWs were identified as exposed to 360 COVID-19 cases. Out of 360, 269 (74.7%) were either admitted or out-patients and 91(26.1%) were HCWs. After risk stratification 890 (26.1%) were categorized as high-risk contacts and 2521 (73.9%) were categorized as low-risk contacts. The test positivity rate of high-risk contact and low-risk contacts were 3.82% and 1.90%, respectively. The average number of high-risk contacts was significantly higher when the COVID-19 case was an admitted patient (6.6) rather than when the COVID-19 case was an HCW (4.0) or outpatient (0.2), p-value = 0.009. Similarly, the average number of high-risk contacts was higher when the COVID-19 case was admitted in non-COVID-19 area (15.8) as compared to COVID-19 area (0.27), p value < 0.001. There was significant decline in mean number of high-risk contacts over the study period. CONCLUSIONS Contact tracing and risk stratification was effective and helped in reducing the number of HCWs going for quarantine. There was also a decline in high-risk contacts during study period suggesting role of implementation of hospital based COVID-19 related infection control strategies. This contact tracing and risk stratification approach designed in the current study can also be implemented in other healthcare settings.

scholarly journals Hospital based contact tracing of COVID-19 patients and health care workers and risk stratification of exposed health care workers during the COVID-19 Pandemic in Eastern India

2020 ◽  
Author(s):  
Durgesh Prasad Sahoo ◽  
Arvind Kumar Singh ◽  
Dinesh Prasad Sahu ◽  
Somen Kumar Pradhan ◽  
Binod Kumar Patro ◽  
...  
Keyword(s):  
Health Care ◽  
High Risk ◽  
Risk Stratification ◽  
Health Care Workers ◽  
Secondary Analysis ◽  
Routine Data ◽  
Low Risk ◽  
Contact Tracing ◽  
P Value ◽  
Care Workers

AbstractIntroductionContact tracing and subsequent quarantining of Health Care Workers (HCWs) is essential to minimize further transmission of COVID-19 infection. In this study, we have reported the yield of Contact Tracing of COVID-19 Patients and HCWs and risk stratification of exposed HCWs.MethodologyThis is a secondary analysis of routine data collected for contact tracing from 19th March to 31st August 2020 at All India Institute of Medical Sciences, Bhubaneswar, Odisha, India. HCWs exposed to COVID-19 infections were categorized as per the risk stratification guidelines and the high-risk contacts were quarantined for 14 days and tested on 7th day from last day of exposure. The low risk contacts were encouraged to closely monitor their symptoms while continuing to work.ResultsOut of 3411 HCWs exposed to COVID 19 patients (n=269) and HCWs (n=91), 890 (26.1%) were high risk contacts and 2521 (73.9%) were low risk contacts. The test positivity rate of high-risk contact was 3.82% and for low risk contact was 1.90%. Average number of high-risk contacts was significantly higher; for admitted patients (6.6) as compared to HCWs (4.0) and outpatients (0.2), p value = 0.009; for patients admitted in non-COVID areas (15.8) as compared to COVID areas (0.27), p value < 0.001; and when clustering of cases was present (14.3) as compared to isolated cases (8.2); p value < 0.001. Trend analysis (15 days block period) showed a significant decline in number of mean numbers of high-risk contacts during the study period.ConclusionContact tracing and risk stratification was effective and helped in reducing the number of HCWs going for quarantine. There was also a decline in high-risk contacts during study period suggesting role of implementation of hospital based COVID related infection control strategies. This contact tracing and risk stratification approach designed in the current study can also be implemented in other healthcare settings.

scholarly journals COVID transmission and contact tracing using WHO risk assement tool among frontline healthcare workers : Insights from a South Indian tertiary care centre

2021 ◽  
Author(s):  
Merlin Moni ◽  
Kiran G Kulirankal ◽  
Preetha Prasanna ◽  
Ann Mary ◽  
Elizabeth Mary Thomas ◽  
...  
Keyword(s):  
Risk Assessment ◽  
High Risk ◽  
Healthcare Workers ◽  
Tertiary Care ◽  
Low Risk ◽  
Contact Tracing ◽  
Tertiary Care Centre ◽  
South Indian ◽  
Shared Space ◽  
Frontline Healthcare Workers

AbstractBackgroundThe high exposure risk to COVID among frontline heathcare workers was a major challenge to healthcare systems across the globe that warranted close monitoring through risk assessment and contact tracing strategies. The objective of our study was to characterize exposure risk factors for transmission and subsequent COVID positivity among the frontlinehealthcare workers in our institution during the pandemic period.MethodsThe retrospective observational study conducted over a period of 6 months from June 2020 to November 2020 at a 1300-bedded South Indian tertiary care centre included frontline healthcare workers who were assessed for their identified encounter with COVID positive individual using a modified WHO COVID risk assessment tool. Additional risk attributes of exposure characterized among COVID positive healthcare workers comprised of shared space, cluster related transmissions and multiple instances of exposure to COVID.ResultsAmong a total of 4744 contacts with COVID positive individuals assessed for risk stratification during the study period, 942 (19.8%) were high risk and 3802 (80.2%) were low risk exposures respectively. 106 (2.2%) turned COVID positive during the surveillance period of 14 days. Frontline workers working in COVID areas had significant low COVID rates as compared to other areas (N=1, 0.9%). The average monthly COVID positivity rates being 1.66%, the attack rates among high risk and low risk contacts among the total HCWs screened were 5% (46/942) and 1.57% (60/3802) respectively. Shared space (70%) and IPC breaches (66%) were found to be highly prevalent in the COVID positive cohort, along with maskless encounters (43%) and multiple exposure (39%). The attack rate among the 6 identified COVID cluster groups (5.5%) were found to be higher than the attack rate (2.2%) noted among the total contacts screened and no significant association was observed between risk categories in the clusters.DiscussionOur study highlights higher risk of COVID positivity among high risk contacts as compared to low risk contacts. However, the high COVID positivity rate in low risk group among cluster transmissions and its lack of association with risk assessment highlight the suboptimal utility of the risk assessment strategy among cluster groups.

scholarly journals Ensuring safety and availability of healthcare workers in the era of COVID-19: An experience from the Eastern State of India

2020 ◽  
Vol 72 ◽  
pp. 58-64 ◽  
Author(s):  
Neeraj Agarwal ◽  
Bijit Biswas ◽  
Rathish Nair
Keyword(s):  
High Risk ◽  
Healthcare Workers ◽  
Health Workers ◽  
Low Risk ◽  
Contact Tracing ◽  
Risk Exposure ◽  
Risk Of Infection ◽  
Healthcare Settings ◽  
Contact Investigation ◽  
Tracing Algorithm

Objectives: The objective of this study was to design a contact tracing algorithm and contact investigation form for healthcare workers deployed in rendering essential health-care services in limitedly resourced healthcare settings during the COVID era. Material and Methods: It was an observational study, longitudinal in design. Based on the existing evidence as of April 15, 2020, we have designed a contact tracing algorithm and contact investigation form to determine the risk of infection among healthcare workers. Later, we have tested the developed contact tracing algorithm and contact investigation from among 28 suspected contacts of a confirmed COVID-19 case admitted in all India Institute of Medical Sciences Patna, Bihar, India. Results: Using the designed contact investigation form, all the 28 suspected contacts of the confirmed COVID-19 case were interviewed, among which only 7(25%) were found to be having high-risk exposure. All persons with high-risk exposure were home quarantined for 5 days, along with their direct contacts. Eventually, all high-risk contacts were tested negative on the 5th day after exposure and immediately joined their duties after that. Those who were at low risk of infection continued to work and self-monitor for COVID compatible symptoms for 14 days. Eventually, none of the low-risk exposure persons developed COVID compatible symptoms, therefore deferred testing. Conclusion: The contact tracing approach designed in the current study is a balanced one where we tried to balance health workers safety without compromising their availability for duty. This approach can also be implemented in other healthcare settings in the era of COVID-19.

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