Epidemiologia, Volume 2, Issue 4 (December 2021) – 11 articles

Nepal was hard hit by a second wave of COVID-19 from April–May 2021. We investigated the transmission dynamics of COVID-19 at the national and provincial levels by using data on laboratory-confirmed RT-PCR positive cases from the official national situation reports. We performed 8 week-to-week sequential forecasts of 10-days and 20-days at national level using three dynamic phenomenological growth models from 5 March 2021–22 May 2021. We also estimated effective and instantaneous reproduction numbers at national and provincial levels using established methods and evaluated the mobility trends using Google’s mobility data. Our forecast estimates indicated a declining trend of COVID-19 cases in Nepal as of June 2021. Sub-epidemic and Richards models provided reasonable short-term projections of COVID-19 cases based on standard performance metrics. There was a linear pattern in the trajectory of COVID-19 incidence during the first wave (deceleration of growth parameter (p) = 0.41–0.43, reproduction number ($R_t$) at 1.1 (95% CI: 1.1, 1.2)), and a sub-exponential growth pattern in the second wave (p = 0.61 (95% CI: 0.58, 0.64)) and $R_t$ at 1.3 (95% CI: 1.3, 1.3)). Across provinces, $R_t$ ranged from 1.2 to 1.5 during the early growth phase of the second wave. The instantaneous $R_t$ fluctuated around 1.0 since January 2021 indicating well sustained transmission. The peak in mobility across different areas coincided with an increasing incidence trend of COVID-19. In conclusion, we found that the sub-epidemic and Richards models yielded reasonable short-terms projections of the COVID-19 trajectory in Nepal, which are useful for healthcare utilization planning. Full article

A key learning lesson from country responses to COVID-19 pandemic was the impact of the strategies that are followed on combating the pandemic. Since the development of different vaccines and their supply globally, most countries have developed their own strategies to effectively provide sufficient doses for their population and start the vaccination process with the best outcomes. In this perspective, we review the African Union vaccination strategy by exploring the implementation of the strategy and its outcomes. We report on the strategy initiatives, vaccines distribution, administration, and the impact on new COVID-19 cases in African countries. Full article

Following exposures to traumatic events on 9/11, survivors have reported heightened levels of posttraumatic stress disorder (PTSD). Multiple factors contribute to both the exacerbation and amelioration of PTSD symptoms, including social integration and support. This cross-sectional study aimed to understand and identify associations of embeddedness and psychosocial risk factors by PTSD status for survivors and first responders of 9/11. Results indicate that those with chronic PTSD had the lowest prevalence of both social and emotional embeddedness and many who reported no PTSD symptoms following 9/11 reported moderate levels of social and emotional embeddedness. Overall, our findings suggest those individuals who reported little to no PTSD also reported the most social/emotional embeddedness; whereas those individuals who report greater or chronic PTSD report the least social/emotional embeddedness. As such, it may be beneficial for clinicians across multiple care disciplines and contexts to consider and address the social lives and needs of those individuals experiencing symptoms of PTSD to ensure their emotional and physical needs are truly being met. Full article

This paper addresses the SARS-CoV-2 vaccination progress in Australia. Globally, Australia was initially praised for its national COVID-19 response, reflecting well with regard to case numbers and mortality rates. However, Australia’s progress with its vaccine rollout has come under scrutiny. When compared globally, it fares very low in terms of the number of vaccine doses administered. This paper discusses the first three months of the vaccination process, and the challenges Australia faced during that time. Through an extensive literature review, data was collected on relevant topics concerning all aspects of the Australian COVID-19 situation. The following key points are discussed: the specific COVID-19 organisation at the federal vs. the state government levels, the Australian economy, the vaccine supply strategy, and the vaccine priority roll out. In conclusion, we highlight the impact of Australia initially relying heavily on the AstraZeneca vaccine, which subsequently came under fire regarding safety issues likely linking the vaccine to thrombosis with thrombocytopenia syndrome (TTS). Full article

Vaccination strategies to lessen the impact of the spread of a disease are fundamental to public health authorities and policy makers. The socio-economic benefit of full return to normalcy is the core of such strategies. In this paper, a COVID-19 vaccination model with efficacy rate is developed and analyzed. The epidemiological parameters of the model are learned via a feed-forward neural network. A hybrid approach that combines residual neural network with variants of recurrent neural network is implemented and analyzed for reliable and accurate prediction of daily cases. The error metrics and a k-fold cross validation with random splitting reveal that a particular type of hybrid approach called residual neural network with gated recurrent unit is the best hybrid neural network architecture. The data-driven simulations confirm the fact that the vaccination rate with higher efficacy lowers the infectiousness and basic reproduction number. As a study case, COVID-19 data for the state of Tennessee in USA is used. Full article

Exploring future physicians’ attitudes toward vaccination is crucial as physicians’ recommendation is the top predictor for individuals to receive vaccines. This study explored the uptake of COVID-19 vaccines and the intention for future booster dose uptake among students at the New York Institute of Technology College of Osteopathic Medicine (NYITCOM). Predictors for actual vaccine and intended booster uptake were also examined. An electronic survey was distributed to Osteopathic Medical Students (OMS I-IV) in the Spring of 2021. A total of 1331 students received the survey, with 316 responses received (24%). In total, 95.3% (301/316) of the respondents reported that they already received vaccines, while 3.1% (13/316) reported that they had not yet received a vaccine. Moreover, 88.9% of the respondents (281/316) were in favor of a booster dose, which was a strong predictor for actual vaccine uptake. We identified that the Asian race, pharmaceutical mistrust, building immunity via vaccines, adequate vaccine testing, and willingness to get non-U.S. manufactured vaccines are the most significant predictors for willingness to accept a booster dose. A very high COVID-19 vaccine uptake among NYITCOM OMS was found in our study. The study also observed a high acceptance of an additional dose of the COVID-19 vaccine in the future. Full article

During the COVID-19 pandemic, Denmark has pursued a mass testing strategy culminating in the testing of 12.167 individuals per 100,000 inhabitants per day during the spring of 2021. The strategy included free access to COVID-19 testing, and since 2021, compulsory documentation for negative tests or vaccination has been required for access to workplace, educational institutions, restaurants, and many other places. Testing and subsequent isolation if testing was positive were voluntary. The present study provides an analysis of whether testing frequency in Denmark showed any correlation to hospitalizations throughout the relevant stages of the pandemic. Mass testing was found not to correlate significantly with the number of hospitalizations during the pandemic. Interestingly, during the highest level of testing in spring 2021 the fraction of positive tests increased slightly; thus, the Danish mass testing strategy, at its best, failed to reduce the prevalence of COVID-19. Furthermore, the relationship between positives in antigen testing and in rt-PCR testing indicated that many patients were not tested early in their infection when the risk of transmission was at the highest. In conclusion, the Danish mass testing strategy for COVID-19 does not appear to have a detectable correlation to the number of hospitalizations due to COVID-19. Full article

In late 2020 and early 2021, with the eagerly anticipated regulatory approval of vaccines against SARS-CoV-2, the urgent global effort to inoculate populations against this devastating virus was underway. These case studies examine the early stages of COVID-19 vaccine rollouts across nine regions from around the world (Brazil, India, Indonesia, Ireland, Israel, Nigeria, Taiwan, United Kingdom and United States). By evaluating and comparing different approaches used to immunize against a novel pathogen, it is possible to learn a great deal about which methods were successful, and in which areas strategies can be improved. This information is applicable to the ongoing global vaccination against this virus, as well as in the event of future pandemics. Research was conducted by following and tracking the progress of vaccine rollouts in the nine regions, using published clinical trials, government documents and news reports as sources of data. Results relate to the proportion of populations that had received at least one COVID-19 dose by 28 February 2021. Outcomes are discussed in the context of three key pillars integral to all immunization programs: procurement of vaccines, communication with the public and distribution of doses to individuals. Full article

The effect of employing collars impregnated with deltamethrin 4% (DM4) to control canine visceral leishmaniasis (CVL) was evaluated. as were the individual factors associated with this infection. A cohort study that included household dogs was conducted between 2002 and 2006. The presence of pathognomonic signals, peridomiciliary sleep habits and breed were the main factors associated with the infection. The use of DM4 collars contributed to the reduction of CVL with an effectiveness of 66%, and the dogs’ survival rate was greater than 90% at 50 months. In conclusion, the adoption of DM4 collars reduced the number of euthanized canines and in the incidence of CVL, and this reduction was sustained for one year after discontinuing the use of the collar. Full article

Despite early control measures, SARS-CoV-2 reached all regions of Peru during the first wave of the pandemic, including native communities of the Peruvian Amazon. Here, we aimed to describe the epidemiological situation of COVID-19 in the Amazonas region of Peru using an open database of 11,124 COVID-19 cases reported from 19 March to 29 July 2020, including 3278 cases from native communities. A high-incidence area in northern Amazonas (Condorcanqui) reported a cumulative incidence of 63.84/1000 inhabitants with a much lower death rate (0.95%) than the national average. Our results showed at least eight significant factors for mortality, and the Native Amazonian ethnicity as a protective factor. Molecular confirmatory tests are necessary to better explain the high incidence of antibody response reported in these communities. Full article

Epidemiological models with constant parameters may not capture satisfactory infection patterns in the presence of pharmaceutical and non-pharmaceutical mitigation measures during a pandemic, since infectiousness is a function of time. In this paper, an Epidemiology-Informed Neural Network algorithm is introduced to learn the time-varying transmission rate for the COVID-19 pandemic in the presence of various mitigation scenarios. There are asymptomatic infectives, mostly unreported, and the proposed algorithm learns the proportion of the total infective individuals that are asymptomatic infectives. Using cumulative and daily reported cases of the symptomatic infectives, we simulate the impact of non-pharmaceutical mitigation measures such as early detection of infectives, contact tracing, and social distancing on the basic reproduction number. We demonstrate the effectiveness of vaccination on the transmission of COVID-19. The accuracy of the proposed algorithm is demonstrated using error metrics in the data-driven simulation for COVID-19 data of Italy, South Korea, the United Kingdom, and the United States. Full article