Epidemiology Of Coronavirus Disease 2019 Research Articles

Neonatal and infant infection with SARS-CoV-2

Despite the substantial body of investigative work describing the Coronavirus Disease 2019 (COVID-19) pandemic, its impact on neonates and infants remains less well characterized. Here, we review the data on epidemiology of COVID-19 in this population. Widespread use of universal testing for SARS-CoV-2 among pregnant persons presenting for delivery complicates interpretation of the risks of perinatal exposure. While many neonates and infants with COVID-19 are well-appearing or have only mild signs of illness, factors such as preterm birth, low birth weight, and medical comorbidities increase the risk of severe infection. We highlight potential protective maternal factors, summarize treatment options and discuss vaccine development. Higher quality data are needed to better inform our understanding of COVID-19 in neonates and infants.

Cost–benefit analysis of the COVID-19 vaccination model incorporating different infectivity reductions

The spread and control of coronavirus disease 2019 (COVID-19) present a worldwide economic and medical burden to public health. It is imperative to probe the effect of vaccination and infectivity reductions in minimizing the impact of COVID-19. Therefore, we analyze a mathematical model incorporating different infectivity reductions. This work provides the most economical and effective control methods for reducing the impact of COVID-19. Using data from Ghana as a sample size, we study the sensitivity of the parameters to estimate the contributions of the transmission routes to the effective reproduction number Re. We also devise optimal interventions with cost–benefit analysis that aim to maximize outcomes while minimizing COVID-19 incidences by deploying cost-effectiveness and optimization techniques. The outcomes of this work contribute to a better understanding of COVID-19 epidemiology and provide insights into implementing interventions needed to minimize the COVID-19 burden in similar settings worldwide.

COVID-19 epidemiology, health services utilisation and health care seeking behaviour during the first year of the COVID-19 pandemic in Mweso health zone, Democratic Republic of Congo.

Although the evidence about coronavirus disease 2019 (COVID-19) has increased exponentially since the beginning of the pandemic, less is known about the direct and indirect effects of the pandemic in humanitarian settings. In the Democratic Republic of the Congo (DRC), most studies occurred in Kinshasa and other cities. Limited research was conducted in remote conflict-affected settings. We investigated the COVID-19 epidemiology, health service utilisation, and health care-seeking behaviour during the first year of the pandemic (March 2020-March 2021) in the Mweso health zone, North Kivu, DRC. This mixed-methods study includes a descriptive epidemiological analysis of reported COVID-19 cases data extracted from the provincial line list, interrupted time series analysis of health service utilisation using routine health service data, qualitative perceptions of health care workers about how health services were affected, and community members' health care seeking behaviour from a representative household survey and focus group discussions. The COVID-19 epidemiology in North Kivu aligns with evidence reported globally, yet case fatality rates were high due to underreporting. Testing capacity was limited and initially mainly available in the province's capital. Health service utilisation showed different patterns - child measles vaccinations experienced a decrease at the beginning of the pandemic, while outpatient consultations, malaria, and pneumonia showed an increase over time. Such increases might have been driven by insecurity and population displacements rather than COVID-19. Community members continued seeking care during the first months of the COVID-19 pandemic and visited the same health facilities as before COVID-19. Financial constraints, not COVID-19, were the main barrier reported to accessing health care. The first year of the COVID-19 pandemic in the Mweso health zone was characterised by low testing capacity and an underestimation of reported COVID-19 infections. The increase in health care utilisation should be further explored to understand the role of factors unrelated to COVID-19, such as insecurity, population displacement, and poverty, which remain major challenges to successfully providing health services and improving the population's health. Measles vaccination coverage dropped, which exacerbated the ongoing measles outbreak. Improved decentralised testing capacity will be crucial for future epidemics and enhanced efforts to maintain child vaccination coverage.

COVID-19 outcome trends by vaccination status in Canada, December 2020-January 2022.

The coronavirus disease 2019 (COVID-19) pandemic in Canada has evolved rapidly. Since late 2020, COVID-19 vaccines have been relied on to protect against severe outcomes in the presence of circulating variants of concern (VOC). This surveillance report provides a retrospective descriptive analysis of national trends in COVID-19 cases and severe outcomes by vaccination status, contextualizing trends against case demographics and circulating VOCs, from December 2020 to January 2022. Case and vaccination coverage surveillance data were obtained from the National COVID-19 Case Dataset and the Canadian COVID-19 Vaccination Coverage Surveillance System for 12 of 13 provinces and territories. Descriptive analyses were produced to describe trends over time among individuals aged 12 years and older by COVID-19 outcome, vaccination status, and demographics. Age-standardized and age-stratified incidence rates and incidence rate ratios were computed for cases, hospitalizations, and deaths. From mid to late-2021, incidence rates for cases and severe outcomes were consistently lowest among those with a completed primary series and highest among those who were unvaccinated. Unvaccinated individuals were much more likely to be hospitalized or to die compared to those with a completed primary series in all variant periods. Age-specific rates of severe outcomes were consistently highest among those aged 80 years and older across all vaccination statuses. Vaccination remains one of the most important public health interventions, particularly among older adults, to protect against COVID-19 severe outcomes as the pandemic evolves. Routine monitoring of COVID-19 outcomes by vaccination status can identify changes in COVID-19 epidemiology and inform public health action and policy.

Overview of COVID-19 Infection, Treatment, and Prevention in Children.

Coronavirus disease 2019 (COVID-19), caused by the novel respiratory virus-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-was declared a global pandemic by the World Health Organization on 11 March 2020. Since then, substantial gains have been made in our understanding of COVID-19 epidemiology, disease presentation, and management. While children tend to have less severe disease courses compared to adults, children can still develop severe COVID-19 infections, particularly in those with underlying medical conditions such as obesity, chronic lung disease, or prematurity. In addition, children are at risk of severe complications of COVID-19 infection, such as multisystem inflammatory syndrome in children (MIS-C) or long COVID. The case definitions of MIS-C and long COVID have continued to evolve with the increased understanding of these new entities; however, improved methods of diagnosis and determination of the optimal management are still needed. Furthermore, with the continued circulation of SARS-CoV-2 variants, there remains a need for clinicians to remain up-to-date on the latest treatment and prevention options. The purpose of this review is to provide an evidence-based review of what we have learned about COVID-19 in children since the start of the pandemic and how best to counsel children and their families on the best methods of prevention.

COVID-19 Rounds": An Inquiry-Based Distance Learning Tool for Medical Students Under Lockdown: A Cross-Sectional Study.

The coronavirus disease 2019 (COVID-19) pandemic presented significant challenges to both clinical practice and the delivery of medical education. Educators and learners implemented novel techniques including distance learning and virtual rounds while trying to stay updated with the surge of information regarding COVID-19 epidemiology, pathogenesis, and treatment. Hence, we designed and implemented a technology enhanced course "COVID-19 Rounds" to educate students about the rapidly evolving pandemic. The objectives of this study are first, to describe a technologically-enhanced course "COVID-19 Rounds" and second, to evaluate the following: a) student satisfaction and program usefulness in achieving pre-set objectives, b) perceived improvement in literacy regarding the pandemic, and c) the impact of student engagement by designing infographics and initiating COVID-19 related research projects. This is a cross-sectional study measuring the impact of the implementation of the "COVID-19 Rounds" on-line course. This program included virtual clinical experiences with physicians on actual rounds in the hospitals and COVID-19 wards, weekly updates on evolving data and new research, and engagement with student-led projects. The study population included 47 fourth-year medical students at the Mohamed Bin Rashid University of Medicine and Health Sciences (MBRU) in Dubai, United Arab Emirates who attended the course. We designed and administered a 47-item survey to assess student satisfaction, program usefulness, impact on knowledge, and student engagement. Data was collected at the end of program delivery via Microsoft forms. A total of 38 out of 47 (81%) fourth-year medical students participated in the study. Final course evaluation revealed an overall high satisfaction rate, with a mean rating of 3.9 (SD 0.94) on the 5-point Likert Scale. Most students were satisfied with course format (27/38; 71%), organization (31/38; 82%) and learning experience (28/38; 74%) that the course offered. The course was particularly useful in offering evidence-based talks about aspects of the pandemic (34/38; 90%), providing weekly updates of emerging evidence (32/38; 84%), enhancing understanding of the challenges of the pandemic (34/38; 90%). Satisfaction with distance learning was moderate (23/37; 62%), and a minority of students would have preferred an in-person version of the course (10/37; 27%). Student engagement in the course was high. All students participated in small group presentations of "infographics" of pandemic related topics. Perceived advantages included conciseness and visual appeal; disadvantages included lack of detail, time consuming requiring design experience. After the course ended 27 students initiated research projects. This resulted in 6 abstracts presented at local meetings and 8 scientific papers published or submitted for publication. This inquiry-based adaptive approach to educate medical students about updates in COVID-19 via virtual learning was successful in achieving objectives and encouraging engagement in research. However, shortcomings of the course related to lack of in-person teaching and clinical activities were also highlighted.

Epidemiologic Study of COVID-19 in Iranian Beta-Thalassemia Patients According to Disease Severity

Background: Thalassemia is a genetic disorder that leads to chronic anemia and requires frequent blood transfusions. With the coronavirus disease 2019 (COVID-19) outbreak, thalassemia patients are at increased risk of disease. Objectives: We aimed to study the epidemiology of COVID-19 in thalassemia patients and its mortality to determine the disease severity. Methods: This cross-section study was conducted in the first year of the pandemic. Provincial information was collected. A questionnaire was developed to collect demographic, clinical, and paraclinical data and outcomes using history, examination, and laboratory tests. The patients' data were analyzed statistically using SPSS (v. 21). Results: The number of thalassemia patients was 19 387, of whom 442 were infected by COVID-19 (50.9% female and 49.1% male), with a mean age of 36.98 years (16 - 67). Of them, 419 had a positive PCR test, and 23 had no positive test. Also, 98% of patients complained of fever, and 54% had cough. Of 442 patients, 14 (3.2%) died, four having a ferritin level > 5000. There was a significant relationship between COVID-19 mortality and increased pulmonary artery pressure (PAP) (P value = 0.003). Also, there was a correlation between COVID-19 mortality and ferritin level (P value = 0.005), while there were no significant correlations between COVID-19 mortality and respiratory symptoms (P value = 0.30), PCR test result (P value = 0.74), and diabetes (P value = 0.47). Conclusions: Thalassemia patients are more prone to COVID-19. Comparing familial and thalassemia patients statistics, the prevalence and percentage of COVID-19 mortality were higher among the patients.

Epidemiology of COVID-19 and the Utility of Cycle Threshold (Ct) Values in Predicting the Severity of Disease.

Advanced molecular diagnostic methods like real-time polymerase chain reaction (PCR) play a vital role in the early recognition of viral infections, including the coronavirus disease 2019 (COVID-19). Therefore, in the context of the recent COVID-19 pandemic, this study aimed to determine the correlation of cycle threshold (Ct) values with symptoms in COVID-19-positive patients. A retrospective study was conducted in a virus research diagnostic laboratory (VRDL) at a COVID-19-dedicated tertiary care hospital in South India. A total of 5563 COVID-19-positive patients were analyzed for symptom spectrum and duration of illness with Ct values of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Around 80% (n= 4401) of the patients were symptomatic and the rest were asymptomatic. Among the symptomatic patients, fever (66%) was the most common symptom. About 44% of symptomatic patients had a low Ct value (Ct ≤ 24). There was a significant difference in symptoms among patients with low, medium, and high Ct values. In the subpopulation of symptomatic patients analyzed for the association of Ct value and duration of illness, the mean duration of illness was three days and almost 88% of the patients were tested within five days of onset of symptoms. It has been observed that a shorter duration of illness lowers the Ct values. A significant association was seen between the mean Ct value and days since symptom onset (p-value = 0.016). Most of the symptomatic patients had lower Ct values in comparison to the asymptomatic patients. A significant association between low Ct values and the duration of symptoms observed in our study explains the viral dynamics, i.e., higher viral shedding at the onset of symptoms and declinesthereafter.

Worldwide impact of COVID-19 on hospital admissions for non-ST-elevation acute coronary syndromes (NSTACS): a systematic review with meta-analysis of 553 038 cases.

How coronavirus disease 2019 (COVID-19) impacted non-ST-segment elevation acute coronary syndromes (NSTACS) is an object of controversial reports. To systematically review studies reporting NSTACS hospitalizations during the COVID-19 pandemic, and analyse whether differences in COVID-19 epidemiology, methodology of report, or public health-related factors could contribute to discrepant findings. Comprehensive search (Medline, Embase, Scopus, Web of Science, Cochrane Register), of studies reporting NSTACS hospitalizations during the COVID-19 pandemic compared with a reference period, following Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. Data were independently extracted by multiple investigators and pooled using a random-effects model. Health-related metrics were from publicly available sources, and analysed through multiple meta-regression modelling. We retrieved 102 articles (553038 NSTACS cases, 40 countries). During peak COVID-19 pandemic, overall incidence rate ratio (IRR) of NSTACS hospitalizations over reference period decreased (0.70, 95% confidence interval (CI) 0.66-0.75; P<0.00001). Significant heterogeneity was detected among studies (I2=98%; P<0.00001). Importantly, wide variations were observed among, and within, countries. No significant differences were observed by study quality, whereas comparing different periods within 2020 resulted in greater decrease (IRR: 0.61; CI: 0.53-0.71) than comparing 2020vs. previous years (IRR: 0.74; CI 0.69-0.79). Among many variables, major predictors of heterogeneity were severe acute respiratory syndrome coronavirus 2 reproduction rate/country, number of hospitals queried, and reference period length; country stringency index and socio-economical indicators did not contribute significantly. During the COVID-19 pandemic, NSTACS hospitalizations decreased significantly worldwide. However, substantial heterogeneity emerged among countries, and within the same country. Factors linked to public health management, but also to methodologies to collect results may have contributed to this heterogeneity. The protocol was registered in the PROSPERO International Prospective Register of Systematic Reviews (ID: CRD42022308159).

COVID-19 infection in people living with HIV.

Coronavirus disease 2019 (COVID-19) and human immunodeficiency virus (HIV) are intersecting pandemics, with implications for care at an individual and global scale. PubMed search with relevant articles and their references reviewed. COVID-19 has changed the delivery of care to people living with HIV (PLWH). Vaccines are efficacious and safe for PLWH; patient care for symptomatic COVID-19 is similar to that of people without HIV. It remains unclear whether PLWH experience increased COVID-19-specific mortality. Treatments to reduce severity in early COVID-19 infection lack evidence in PLWH. The effects of the COVID-19 pandemic on HIV-related morbidity and mortality are yet to be seen. COVID-19 epidemiology among PLWH is complicated by changes to the severe acute respiratory syndrome coronavirus 2, population behaviours and vaccine availability. Global trends in HIV-related morbidity and mortality should be monitored to appreciate the effects of the COVID-19 pandemic. The benefits of early antiviral and/or neutralizing monoclonal antibody (nMAb) treatment for PLWH and nMAb prophylaxis require investigation.

COVID-19 and smoking: Considerations after two years

COVID-19 and smoking: Considerations after two years

Epidemiology and Clinical Features of COVID-19 among 4,015 Neonates in Iran: Results of the National Study from the Iranian Maternal and Neonatal Network.

The coronavirus disease 2019 (COVID-19) pandemic had a significant impact on pregnant women and neonates in Iran. This retrospective study describes the national experience among neonates having suspected and confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection following hospital admission to examine the epidemiology, demographic, and clinical features. All nationwide cases of suspected and confirmed neonatal SARS-CoV-2 infection were drawn from the Iranian Maternal and Neonatal Network (IMaN) between February 2020 and February 2021. IMaN registers demographic, maternal, and neonatal health data throughout Iran. Statistical analysis of demographic, epidemiological, and clinical data were performed. There were 4,015 liveborn neonates having suspected or confirmed SARS-CoV-2 infection that fulfilled the study inclusion criteria identified in the IMaN registry from 187 hospitals throughout Iran. There were 1,392 (34.6%) neonates that were preterm, including 304 (7.6%) less than 32 weeks' gestation. Among the 2,567 newborns admitted to the hospital immediately after birth, the most common clinical problems were respiratory distress (1,095 cases; 42.6%), sepsis-like syndrome (355; 13.8%), and cyanosis (300 cases; 11.6%). Of 683 neonates transferred from another hospital, the most frequent problems were respiratory distress (388; 56.8%), sepsis-like syndrome (152; 22.2%), and cyanosis (134; 19.6%). Among 765 neonates discharged home after birth and subsequently admitted to the hospital, sepsis-like syndrome (244 cases; 31.8%), fever (210; 27.4%), and respiratory distress (185; 24.1%) were most frequent. A total of 2,331 (58%) of neonates required respiratory care, with 2,044 surviving and 287 having a neonatal death. Approximately 55% of surviving neonates received respiratory support, compared with 97% of neonates who expired. Laboratory abnormalities included elevations of white blood cell count, creatine phosphokinase, liver enzymes, and C-reactive protein. This report adds the national experience of Iran to the list of reports from multiple countries describing their experience with COVID-19 in neonates, demonstrating that newborns are not exempt from COVID-19-morbidity and mortality. · Most common clinical problem was respiratory distress.. · Sepsis-like syndrome was also frequently present.. · A total of 58% of all neonates required respiratory care..

A Review of Crucial Radiological Investigations in the Management of COVID-19 Cases.

Chest X-ray, chest CT, and lung ultrasound are the most common radiological interventions used in the diagnosis and management of coronavirus disease 2019 (COVID-19) patients. The purpose of this literature review, which was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, is to determine which radiological investigation is crucial for that purpose.PubMed, Medline, American Journal of Radiology (AJR), Public Library of Science (PLOS), Elsevier, National Center for Biotechnology Information (NCBI), and ScienceDirect were explored. Seventy-two articles were reviewed for potential inclusion, including 50 discussing chest CT, 15 discussing chest X-ray, five discussing lung ultrasound, and two discussing COVID-19 epidemiology. The reported sensitivities and specificities for chest CT ranged from 64 to 98% and 25 to 88%, respectively. The reported sensitivities and specificities for chest X-rays ranged from 33 to 89% and 11.1 to 88.9%, respectively. The reported sensitivities and specificities for lung ultrasound ranged from 93 to 96.8% and 21.3 to 95%, respectively. The most common findings on chest CT include ground glass opacities and consolidation. The most common findings on chest X-rays include opacities, consolidation, and pleural effusion. The data indicate that chest CT is the most effective radiological tool for the diagnosis and management of COVID-19 patients. The authors support the continued use of reverse transcription polymerase chain reaction (RT-PCR), along with physical examination and contact history, for such diagnosis. Chest CT could be more appropriate in emergency situations when quick triage of patients is necessary before RT-PCR results are available. CT can also be used to visualize the progression of COVID-19 pneumonia and to identify potential false positive RT-PCR results. Chest X-ray and lung ultrasound are acceptable in situations where chest CT is unavailable or contraindicated.

Epidemiology of COVID-19 in two cities in southern Brazil: a cross-sectional population-based study

The first recommendations to prevent coronavirus disease 2019 (COVID-19) were made without epidemiological information on what would be people’s behaviors in view of the biopsychosocial and physical effects of confinement because of a health emergency with great economic impact. Objective: To determine the incidence of COVID-19; analyze the associated behavioral and sociodemographic factors. Methods: Cross-sectional population-based study with a representative sample of two cities in southern Brazil. 2,170 individuals aged 18 years or over were interviewed from October 2020 to January 2021. Data were collected in person at the place of residence of the individuals using a questionnaire. Results: The incidence of COVID-19 was 6.8% (95% confidence interval, CI: 5.4; 8.4), and was significantly higher in white people, aged between 18 and 59 years, married, with higher education, higher family income, and who lived in an apartment. The incidence of COVID-19 was associated with diabetes. People who stayed less time at home has a higher incidence (3.7% versus 7.5%). The most reported symptoms were excessive tiredness, reduced smell and taste. Most of the individuals (85%) sought a health facility and less than 5% were hospitalized. Conclusion: Almost one in ten individuals was infected by COVID-19. The incidence was higher for adults (because of being more exposed), individuals from higher socioeconomic level (because of having tested more) and in diabetics. Almost everyone stayed home after being diagnosed with the virus, and the main risk factor was having contact with someone infected.

Maternal and Newborn Hospital Outcomes of Perinatal SARS-CoV-2 Infection: A National Registry.

The American Academy of Pediatrics National Registry for the Surveillance and Epidemiology of Perinatal coronavirus disease 2019 (COVID-19) (NPC-19) was developed to provide information on the effects of perinatal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. National Registry for the Surveillance and Epidemiology of Perinatal COVID-19 participating centers entered maternal and newborn data for pregnant persons who tested positive for SARS-CoV-2 infection between 14 days before and 10 days after delivery. Incidence of and morbidities associated with maternal and newborn SARS-CoV-2 infection were assessed. From April 6, 2020 to March 19, 2021, 242 centers in the United States centers reported data for 7524 pregnant persons; at the time of delivery, 78.1% of these persons were asymptomatic, 18.2% were symptomatic but not hospitalized specifically for COVID-19, 3.4% were hospitalized for COVID-19 treatment, and 18 (0.2%) died in the hospital of COVID-related complications. Among 7648 newborns, 6486 (84.8%) were tested for SARS-CoV-2, and 144 (2.2%) were positive; the highest rate of newborn infection was observed when mothers first tested positive in the immediate postpartum period (17 of 125, 13.6%). No newborn deaths were attributable to SARS-CoV-2 infection. Overall, 15.6% of newborns were preterm: among tested newborns, 30.1% of polymerase chain reaction-positive and 16.2% of polymerase chain reaction-negative were born preterm (P < .001). Need for mechanical ventilation did not differ by newborn SARS-CoV-2 test result, but those with positive tests were more likely to be admitted to a NICU. Early in the pandemic, SARS-CoV-2 infection was acquired by newborns at variable rates and without apparent short-term effects. During a period that preceded widespread availability of vaccines, we observed higher than expected numbers of preterm births and maternal in-hospital deaths.

Inference from Open-Source Sequence Data on the Genetic Epidemiology of COVID-19 Infection in Africa

Between late December 2019 when it was first reported, to early September 2020, severe acute respiratory syndrome coronavirus-2 (SARSCoV- 2), the causative agent of coronavirus disease-2019 (COVID-19), reportedly infected over 10 million people globally. In Africa, more than 300,000 infections occurred within the period, from which several genetic sequences of the virus were generated. During disease outbreak, phylogenetic reconstruction of genomic data can assist in making epidemiological inferences about time of pathogen introduction, epidemic growth rate and temporal-spatial spread of the infection. In this work, we studied the genetic epidemiology of COVID-19 in Africa. Genetic sequence data of SARS-CoV-2 and metadata from African countries were obtained from publicly accessible sequence database hosted by the GISAID initiative. Whole genome sequences were subjected to multiple sequence alignment and the aligned sequences used to construct a Maximum Likelihood phylogenetic tree based on the general time reversible model. Of the 227 genetic sequences obtained for 9 African countries (DRC=133, Senegal=23, South Africa=20, Ghana=15, Tunisia=6, Algeria=3, Gambia=3, Egypt=2 and Nigeria=2), 220 were whole genome sequences while 7 were partial genome sequences of the surface glycoprotein S. Majority of the viruses (58.1%) belonged to the G clade of GISAID classification. Phylogenetic analysis confirmed multiple introductions of the virus to the continent from multiple external sources prior to local adaptation and spread. The very close alignment of three viruses - Ghana/1659_S14/2020|EPI_ISL_422405, DRC/KN0054/2020|EPI_ ISL_417437, and South_Africa/R05475/2020|EPI_ISL_435059 – to the reference Wuhan strain on the time tree, suggests possible introduction and circulation of the virus into the continent much earlier than when the first case in the continent was announced in February 15 2020. In conclusion, this study provided evidence to support multiple introductions of SARSCoV- 2 into Africa, and further suggests that the virus may have already been circulating in the continent prior to official reporting of the first case. Also, there is strong impression to infer likely genetic adaptation of the virus in the continent that may account for the close clustering of isolates from different countries of the continent.

An epidemiological evaluation of COVID-19 in La paz, Bolivia

IntroductionThe Plurinational State of Bolivia (Bolivia) has experienced four major waves of coronavirus disease 2019 (COVID-19) so far. Although the ministry of health has been tracking morbidity and mortality through each wave, epidemiology of COVID-19 in Bolivia is not well defined, despite a need for more accurate measurement of the number of cases and deaths to allow for forecasting of the pandemic. This study examined prevalence of COVID-19 at community level, determinants of its occurrence and vaccine effectiveness. MethodsWe conducted a cross-sectional study in La Paz city on 2,775 individuals between March 2020 and February 2022. A structured questionnaire was used to collect data on COVID-19 morbidity, mortality and vaccination status. ResultsOf the 2,775 participants, 1,586 (57.1%) were infected with COVID-19, and 187 (6.7%) were suspected cases. The mortality rate was 2.9%. Sinopharm, Johnson & Johnson, Gamaleya, Pfizer-BioNtech, Moderna and AstraZeneka vaccines are in use, and all vaccines have demonstrated effectiveness in reducing the risk of onset. Risk for mortality was significantly lower in the vaccinated group with an odds ratio of 0.037 (95％ confidential interval: 0.01–0.10, p-value: <0.001). ConclusionsActual prevalence of COVID-19 in La Paz (the prevalence rate: 63.8%, including suspected case) was higher than that reported by the Ministry of Health and Sports in Bolivia (7.5%). In addition, vaccination has contributed significantly to the control of the COVID-19 epidemic in Bolivia. We believe that our report will be useful for COVID-19 prevention strategies in Bolivia for the future.

Infection of healthcare workers despite a high vaccination rate during the fifth wave of COVID-19 due to Omicron variant in Hong Kong

No nosocomial infection was recorded in our healthcare workers (HCWs) during the early phase of the coronavirus disease 2019 (COVID-19) pandemic. With the emergence of the Omicron variant of increased transmissibility, infection in HCWs occurred as expected. We aimed to study the epidemiology of infection in HCWs and to describe the infection control measures during the outbreak of the Omicron variant. With daily rapid antigen testing and molecular confirmation test for COVID-19, infected HCWs were interviewed by infection control nurses (ICNs) to investigate the potential source of infection. The epidemiology of COVID-19 in Hong Kong served as reference. During the fifth wave of COVID-19 (31 December 2021 to 31 May 2022), 1,200,068 cases were reported (incidence 95 times higher than in preceding waves in Hong Kong; 162,103 vs 1,707 per million population respectively, p<0.001). The proportion of infected HCWs was significantly higher than that of the general population (24.9%, 1,607/6,452 vs 16.2%, 12,000,068/7,403,100 respectively; p<0.01). The proportion of infected non-clinical staff was significantly higher than that of clinical staff (31.8%, 536/1,687 vs 22.5%, 1,071/4,765 respectively; p<0.001). Of 82.8% (1,330/1,607) infected HCWs interviewed by ICNs, 99.5% (1,324/1,330) had been fully vaccinated; 49.5% (659/1,330) had no identifiable source; 40.7% (541/1,330) were probably infected from household members; 9.8% (130/1,330) had possible exposure to confirmed patients or HCWs, but no lapse in infection control measures or inappropriate use of personal protective equipment was recalled. Omicron variant is highly transmissible such that breakthrough infection occurred despite high level of vaccination.

Epidemiology of COVID-19 in Kish Island from February to August 2020

Background: In March 2020, the world health organization declared the outbreak of novel coronavirus disease 2019 (COVID-19) as a pandemic. COVID-19 is a highly contagious disease. Kish is a touristic island that is located in the south of Iran. The aim of the present study was to investigate the epidemiology of COVID-19 on Kish island. Methods: In the present cross-sectional study, the residents of Kish Island, Iran, who were checked with COVID-19 polymerase chain reaction (PCR) test from February to August 2020 were included. The PCR test was obtained from symptomatic individuals or those people who had exposure to suspected COVID-19 cases. Data were collected from their medical records and analyzed based on their PCR test results. Results: A total of 4859 individuals were checked with COVID-19 PCR test. The result was positive in 1251 (25.75%) cases and negative in 3608 (74.25%). The mean age was 37.32 years. The majority of the individuals were men. Most of the participants were office employees. The number of housewives was approximately double in COVID-19 positive patients compared with the patients with negative results. About 40% of the individuals with positive results had a history of exposure to suspected COVID-19 cases. The prevalence of exposure to suspected COVID-19 cases and recent travel was significantly higher among positive cases (P&lt;0.001). There was a significant correlation between the delay between the onset of the symptoms and performing PCR. Longer delays were seen among the deceased patients. Conclusion: It seems that more precise policies should be taken to avoid contact with symptomatic patients and people who had a history of travel to the island.

Epidemiology of Neonatal COVID-19 in the United States.

Data on coronavirus disease 2019 (COVID-19) infections in neonates are limited. We aimed to identify and describe the incidence, presentation, and clinical outcomes of neonatal COVID-19. Over 1 million neonatal encounters at 109 United States health systems, from March 2020 to February 2021, were extracted from the Cerner Real World Database. COVID-19 diagnosis was assessed using severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) laboratory tests and diagnosis codes. Incidence of COVID-19 per 100 000 encounters was estimated. COVID-19 was diagnosed in 918 (0.1%) neonates (91.1 per 100 000 encounters [95% confidence interval 85.3-97.2]). Of these, 71 (7.7%) had severe infection (7 per 100 000 [95% confidence interval 5.5-8.9]). Median time to diagnosis was 14.5 days from birth (interquartile range 3.1-24.2). Common signs of infection were tachypnea and fever. Those with severe infection were more likely to receive respiratory support (50.7% vs 5.2%, P < .001). Severely ill neonates received analgesia (38%), antibiotics (33.8%), anticoagulants (32.4%), corticosteroids (26.8%), remdesivir (2.8%), and COVID-19 convalescent plasma (1.4%). A total of 93.6% neonates were discharged home after care, 1.1% were transferred to another hospital, and discharge disposition was unknown for 5.2%. One neonate (0.1%) with presentation suggestive of multisystem inflammatory syndrome in children died after 11 days of hospitalization. Most neonates infected with SARS-CoV-2 were asymptomatic or developed mild illness without need for respiratory support. Some had severe illness requiring treatment of COVID-19 with remdesivir and COVID-19 convalescent plasma. SARS-CoV-2 infection in neonates, though rare, may result in severe disease.