COVID-19 Variants, Vaccines and New Waves

A special issue of Tropical Medicine and Infectious Disease (ISSN 2414-6366). This special issue belongs to the section "Infectious Diseases".

Deadline for manuscript submissions: closed (31 December 2023) | Viewed by 31574

Special Issue Editor


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Guest Editor
1. International Health Policy Program, Ministry of Public Health, Nonthaburi 11000, Thailand
2. Division of Epidemiology, Department of Disease Control, Ministry of Public Health, Nonthaburi 11000, Thailand
Interests: cost effectiveness; field epidemiology; econometrics; clinical epidemiology; genomics; mathematical modelling

Special Issue Information

Dear Colleagues,

During the past few years, COVID-19 has had a massive impact on human health all over the globe. It is evident that the Delta and the Omicron variants created unprecedented public health calamity. Death tolls all over the world soared, and the health systems in many countries almost collapsed during the peak of the pandemic. COVID-19 vaccines are universally believed to be one of the most effective weapons to halt the pandemic. Though it is anticipated that the pandemic will have subsided by late 2023, the situation is extremely dynamic, and scientists and experts remain vigilant, observing trends to identify the emergence of any new waves. Therefore, a clear understanding of the current situation and forecasted trends of COVID-19 is incredibly important, and further studies on SARS-CoV-2 variants and the vaccines are of great value for public health planning. We also welcome any studies related but not limited to SARS-CoV-2 variants, COVID-19 epidemiology, vaccine effectiveness, vaccine hesitancy, and vaccine prioritization. It is hoped that a better understanding on these issues will lead to better policy decisions that address any pandemics that may occur in the future.

Dr. Rapeepong Suphanchaimat
Guest Editor

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Keywords

  • vaccine effectiveness
  • SARS-CoV-2 variants
  • vaccine hesitancy
  • vaccine efficacy
  • COVID-19 epidemiology
  • COVID-19 waves

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Published Papers (14 papers)

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18 pages, 2980 KiB  
Article
A Longitudinal Study in Tunisia to Assess the Anti-RBD IgG and IgA Responses Induced by Three Different COVID-19 Vaccine Platforms
by Wafa Ben Hamouda, Mariem Hanachi, Sonia Ben Hamouda, Wafa Kammoun Rebai, Adel Gharbi, Amor Baccouche, Jihene Bettaieb, Oussema Souiai, Mohamed Ridha Barbouche, Koussay Dellagi, Melika Ben Ahmed and Chaouki Benabdessalem
Trop. Med. Infect. Dis. 2024, 9(3), 61; https://doi.org/10.3390/tropicalmed9030061 - 13 Mar 2024
Viewed by 1873
Abstract
Background: Vaccination constitutes the best strategy against COVID-19. In Tunisia, seven vaccines standing for the three main platforms, namely RNA, viral vector, and inactivated vaccines, have been used to vaccinate the population at a large scale. This study aimed to assess, in our [...] Read more.
Background: Vaccination constitutes the best strategy against COVID-19. In Tunisia, seven vaccines standing for the three main platforms, namely RNA, viral vector, and inactivated vaccines, have been used to vaccinate the population at a large scale. This study aimed to assess, in our setting, the kinetics of vaccine-induced anti-RBD IgG and IgA antibody responses. Methods: Using in-house developed and validated ELISA assays, we measured anti-RBD IgG and IgA serum antibodies in 186 vaccinated workers at the Institut Pasteur de Tunis over 12 months. Results: We showed that RNA vaccines were the most immunogenic vaccines, as compared to alum-adjuvanted inactivated and viral-vector vaccines, either in SARS-CoV-2-naïve or in SARS-CoV-2-experienced individuals. In addition to the IgG antibodies, the vaccination elicited RBD-specific IgAs. Vaccinated individuals with prior SARS-CoV-2 infection exhibited more robust IgG and IgA antibody responses, as compared to SARS-CoV-2-naïve individuals. Conclusions: After following up for 12 months post-immunization, we concluded that the hierarchy between the platforms for anti-RBD antibody-titer dynamics was RNA vaccines, followed by viral-vector and alum-adjuvanted inactivated vaccines. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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17 pages, 3021 KiB  
Article
Genomic and Phylogenetic Characterisation of SARS-CoV-2 Genomes Isolated in Patients from Lambayeque Region, Peru
by Sergio Luis Aguilar-Martinez, Gustavo Adolfo Sandoval-Peña, José Arturo Molina-Mora, Pablo Tsukayama-Cisneros, Cristian Díaz-Vélez, Franklin Rómulo Aguilar-Gamboa, D. Katterine Bonilla-Aldana and Alfonso J. Rodriguez-Morales
Trop. Med. Infect. Dis. 2024, 9(2), 46; https://doi.org/10.3390/tropicalmed9020046 - 11 Feb 2024
Cited by 2 | Viewed by 2410
Abstract
Objective: this study aims to identify and characterise genomic and phylogenetically isolated SARS-CoV-2 viral isolates in patients from Lambayeque, Peru. Methods: Nasopharyngeal swabs were taken from patients from the Almanzor Aguinaga Asenjo Hospital, Chiclayo, Lambayeque, Peru, which had been considered mild, moderate, and [...] Read more.
Objective: this study aims to identify and characterise genomic and phylogenetically isolated SARS-CoV-2 viral isolates in patients from Lambayeque, Peru. Methods: Nasopharyngeal swabs were taken from patients from the Almanzor Aguinaga Asenjo Hospital, Chiclayo, Lambayeque, Peru, which had been considered mild, moderate, and severe cases of COVID-19. Patients had to have tested positive for COVID-19, using a positive RT-PCR for SARS-CoV-2. Subsequently, the SARS-CoV-2 complete viral genome sequencing was carried out using Illumina MiSeq®. The sequences obtained from the sequence were analysed in Nextclade V1.10.0 to assign the corresponding clades, identify mutations in the SARS-CoV-2 genes and perform quality control of the sequences obtained. All sequences were aligned using MAFFT v7.471. The SARS-CoV-2 isolate Wuhan NC 045512.2 was used as a reference sequence to analyse mutations at the amino acid level. The construction of the phylogenetic tree model was achieved with IQ-TREE v1.6.12. Results: It was determined that during the period from December 2020 to January 2021, the lineages s C.14, C.33, B.1.1.485, B.1.1, B.1.1.1, and B.1.111 circulated, with lineage C.14 being the most predominant at 76.7% (n = 23/30). These lineages were classified in clade 20D mainly and also within clades 20B and 20A. On the contrary, the variants found in the second batch of samples of the period from September to October 2021 were Delta (72.7%), Gamma (13.6%), Mu (4.6%), and Lambda (9.1%), distributed between clades 20J, 21G, 21H, 21J, and 21I. Conclusions: This study reveals updated information on the viral genomics of SARS-CoV-2 in the Lambayeque region, Peru, which is crucial to understanding the origins and dispersion of the virus and provides information on viral pathogenicity, transmission and epidemiology. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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12 pages, 2081 KiB  
Article
Mortality Trend of Severe COVID-19 in Under-Vaccinated Population Admitted to ICU in French Amazonia
by Séverine Matheus, Stéphanie Houcke, Guy Roger Lontsi Ngoulla, Nicolas Higel, Abesetou Ba, Fabrice Cook, Cyrille Gourjault, Flaubert Nkontcho, Magalie Demar, Mathieu Nacher, Félix Djossou, Didier Hommel, Dabor Résiere, Jean Marc Pujo and Hatem Kallel
Trop. Med. Infect. Dis. 2024, 9(1), 15; https://doi.org/10.3390/tropicalmed9010015 - 5 Jan 2024
Viewed by 2049
Abstract
(1) Background: Until December 2021, French Guiana (FG), located in South America, faced four consecutive COVID-19 epidemic waves. This study sought to analyze the mortality trend of severe COVID-19 patients admitted to the referral ICU of FG. (2) Methods: We conducted a prospective, [...] Read more.
(1) Background: Until December 2021, French Guiana (FG), located in South America, faced four consecutive COVID-19 epidemic waves. This study sought to analyze the mortality trend of severe COVID-19 patients admitted to the referral ICU of FG. (2) Methods: We conducted a prospective, observational, and non-interventional study in ICU at Cayenne Hospital. We included 383 patients older than 18 admitted with SARS-CoV-2-related pneumonia hospitalized from May 2020 to December 2021. The study covers three periods. Period 1 (Waves 1 and 2, original variant), period 2 (Wave 3, Gamma variant), and period 3 (Wave 4, Delta variant). (3) Results: The median age was 63 years (52–70). Frailty was diagnosed in 36 patients over 70 (32.4%). Only 4.8% of patients were vaccinated. The median ICU LOS was 10 days (6–19). Hospital mortality was 37.3%. It was 30.9% in period 1, 36.6% in period 2 (p = 0.329 vs. period 1), and 47.1% in period 3 (0.015 vs. period 1). In multivariate analysis, independent factors associated with hospital mortality included age greater than 40 years (]40–60 years] OR = 5.2, 95%CI: 1.4–19.5; (]60–70 years] OR = 8.5, 95%CI: 2.2–32; (]70+ years] OR = 17.9, 95%CI: 4.5–70.9), frailty (OR = 5.6, 95%CI: 2.2–17.2), immunosuppression (OR = 2.6, 95%CI: 1.05–6.7), and MV use (OR = 11, 95%CI: 6.1–19.9). This model had an overall sensitivity of 72%, a specificity of 80.4%, a positive predictive value of 68.7%, and a negative predictive value of 82.8%. (4) Conclusions: The mortality of severe COVID-19 patients in French Amazonia was higher during the Delta variant wave. This over-death could be explained by the virulence of the responsible SARS-CoV-2 variant and the under-vaccination coverage of the studied population. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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16 pages, 4666 KiB  
Article
Development of an Optimized Process for Functional Recombinant SARS-CoV-2 Spike S1 Receptor-Binding Domain Protein Produced in the Baculovirus Expression Vector System
by Mohamed Boumaiza, Ameni Chaabene, Ines Akrouti, Meriem Ben Zakour, Hana Askri, Said Salhi, Wafa Ben Hamouda, Soumaya Marzouki, Chaouki Benabdessalem, Melika Ben Ahmed, Khaled Trabelsi and Samia Rourou
Trop. Med. Infect. Dis. 2023, 8(11), 501; https://doi.org/10.3390/tropicalmed8110501 - 16 Nov 2023
Cited by 3 | Viewed by 2401
Abstract
To map the spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and evaluate immune response variations against this virus, it is essential to set up efficient serological tests locally. The SARS-CoV-2 immunogenic proteins were very expensive and not affordable for lower- middle-income [...] Read more.
To map the spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and evaluate immune response variations against this virus, it is essential to set up efficient serological tests locally. The SARS-CoV-2 immunogenic proteins were very expensive and not affordable for lower- middle-income countries (LMICs). For this purpose, the commonly used antigen, receptor-binding domain (RBD) of spike S1 protein (S1RBD), was produced using the baculovirus expression vector system (BEVS). In the current study, the expression of S1RBD was monitored using Western blot under different culture conditions. Different parameters were studied: the multiplicity of infection (MOI), cell density at infection, and harvest time. Hence, optimal conditions for efficient S1RBD production were identified: MOI 3; cell density at infection 2–3 × 106 cells/mL; and time post-infection (tPI or harvest time) of 72 h and 72–96 h, successively, for expression in shake flasks and a 7L bioreactor. A high production yield of S1RBD varying between 4 mg and 70 mg per liter of crude cell culture supernatant was achieved, respectively, in the shake flasks and 7L bioreactor. Moreover, the produced S1RBD showed an excellent antigenicity potential against COVID-19 (Wuhan strain) patient sera evaluated by Western blot. Thus, additional serological assays, such as in-house ELISA and seroprevalence studies based on the purified S1RDB, were developed. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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28 pages, 5342 KiB  
Article
Mathematical Modeling of SARS-CoV-2 Transmission between Minks and Humans Considering New Variants and Mink Culling
by Mahmoud A. Ibrahim and Attila Dénes
Trop. Med. Infect. Dis. 2023, 8(8), 398; https://doi.org/10.3390/tropicalmed8080398 - 3 Aug 2023
Viewed by 1967
Abstract
We formulated and studied mathematical models to investigate control strategies for the outbreak of the disease caused by SARS-CoV-2, considering the transmission between humans and minks. Two novel models, namely SEIR and SVEIR, are proposed to incorporate human-to-human, human-to-mink, and mink-to-human transmission. We [...] Read more.
We formulated and studied mathematical models to investigate control strategies for the outbreak of the disease caused by SARS-CoV-2, considering the transmission between humans and minks. Two novel models, namely SEIR and SVEIR, are proposed to incorporate human-to-human, human-to-mink, and mink-to-human transmission. We derive formulas for the reproduction number R0 for both models using the next-generation matrix technique. We fitted our model to the daily number of COVID-19-infected cases among humans in Denmark as an example, and using the best-fit parameters, we calculated the values of R0 to be 1.58432 and 1.71852 for the two-strain and single-strain models, respectively. Numerical simulations are conducted to investigate the impact of control measures, such as mink culling or vaccination strategies, on the number of infected cases in both humans and minks. Additionally, we investigated the possibility of the mutated virus in minks being transmitted to humans. Our results indicate that to control the disease and spread of SARS-CoV-2 mutant strains among humans and minks, we must minimize the transmission and contact rates between mink farmers and other humans by quarantining such individuals. In order to reduce the virus mutation rate in minks, culling or vaccination strategies for infected mink farms must also be implemented. These measures are essential in managing the spread of SARS-CoV-2 and its variants, protecting public health, and mitigating the potential risks associated with human-to-mink transmission. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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14 pages, 322 KiB  
Article
Clinical Evolution and Risk Factors in Patients Infected during the First Wave of COVID-19: A Two-Year Longitudinal Study
by Carlos Rescalvo-Casas, Ramón Pérez-Tanoira, Rocío Fernández Villegas, Marcos Hernando-Gozalo, Laura Seijas-Pereda, Felipe Pérez-García, Helena Moza Moríñigo, Peña Gómez-Herruz, Teresa Arroyo, Rosa González, Cristina Verdú Expósito, Lourdes Lledó García, Juan Romanyk Cabrera and Juan Cuadros-González
Trop. Med. Infect. Dis. 2023, 8(7), 340; https://doi.org/10.3390/tropicalmed8070340 - 25 Jun 2023
Cited by 1 | Viewed by 2026
Abstract
A limited number of longitudinal studies have examined the symptoms associated with long-COVID-19. We conducted an assessment of symptom onset, severity and patient recovery, and determined the percentage of patients who experienced reinfection up to 2 years after the initial onset of the [...] Read more.
A limited number of longitudinal studies have examined the symptoms associated with long-COVID-19. We conducted an assessment of symptom onset, severity and patient recovery, and determined the percentage of patients who experienced reinfection up to 2 years after the initial onset of the disease. Our cohort comprises 377 patients (≥18 years) with laboratory-confirmed COVID-19 in a secondary hospital (Madrid, Spain), throughout March 3–16, 2020. Disease outcomes and clinical data were followed-up until August 12, 2022. We reviewed the evolution of the 253 patients who had survived as of April 2020 (67.1%). Nine died between April 2020 and August 2022. A multivariate regression analysis performed to detect the risk factors associated with long-COVID-19 revealed that the increased likelihood was associated with chronic obstructive lung disease (OR 14.35, 95% CI 1.89–109.09; p = 0.010), dyspnea (5.02, 1.02–24.75; p = 0.048), higher LDH (3.23, 1.34–7.52; p = 0.006), and lower D-dimer levels (0.164, 0.04–0.678; p = 0.012). Reinfected patients (n = 45) (47.8 years; 39.7–67.2) were younger than non-reinfected patients (64.1 years; 48.6–74.4)) (p < 0.001). Patients who received a combination of vaccines exhibited fewer symptoms (44.4%) compared to those who received a single type of vaccine (77.8%) (p = 0.048). Long-COVID-19 was detected in 27.05% (66/244) of patients. The early detection of risk factors helps predict the clinical course of patients with COVID-19. Middle-aged adults could be susceptible to reinfection, highlighting the importance of prevention and control measures regardless of vaccination status. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
13 pages, 699 KiB  
Article
COVID-19 Cases and Deaths among Healthcare Personnel with the Progression of the Pandemic in Korea from March 2020 to February 2022
by Yeonju Kim, Sung-Chan Yang, Jinhwa Jang, Shin Young Park, Seong Sun Kim, Chansoo Kim, Donghyok Kwon and Sang-Won Lee
Trop. Med. Infect. Dis. 2023, 8(6), 308; https://doi.org/10.3390/tropicalmed8060308 - 5 Jun 2023
Cited by 2 | Viewed by 1914
Abstract
Healthcare personnel (HCP) are vulnerable to COVID-19 infection due to their higher risk of contact with infected persons. The numbers of cases and deaths among HCP in Korea were divided into four periods associated with different major variants of SARS-CoV-2: GH clade, Alpha, [...] Read more.
Healthcare personnel (HCP) are vulnerable to COVID-19 infection due to their higher risk of contact with infected persons. The numbers of cases and deaths among HCP in Korea were divided into four periods associated with different major variants of SARS-CoV-2: GH clade, Alpha, Delta, and Omicron. To evaluate the implication of HCP infection in Korea, we overviewed the pandemic status in Korea and in other countries: the cases, deaths, excess mortality, and vaccination rates in Germany, Israel, Italy, Japan, the United Kingdom, and the United States. In about two years, there were 10,670 HCP cases among all COVID-19 cases (1.15% of 925,975 cases). HCP cases had a lower death rate (%) compared to that for all cases (0.14 versus 0.75). Nurses were the most infected (55.3%), followed by HCP of other categories (28.8%) and doctors (15.9%), while deaths were mostly reported among doctors (9 out of 15, 60%). Cases among HCP gradually increased, but the death rate decreased as the pandemic progressed. Compared to five of the other countries examined, Korea had a higher incidence of cases but a lower mortality, lower excess mortality, and a higher vaccination rate. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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19 pages, 4468 KiB  
Article
Asymptomatic and Mild SARS-CoV-2 Infections in a Hungarian Outpatient Cohort in the First Year of the COVID-19 Pandemic
by István Jankovics, Cecília Müller, Éva Gönczöl, Ildikó Visontai, István Varga, Márta Lőrincz, Dávid Kuti, Ágnes Hasitz, Péter Malik, Krisztina Ursu, Borbála Bányász, Júlia Sarkadi and Béla Dénes
Trop. Med. Infect. Dis. 2023, 8(4), 204; https://doi.org/10.3390/tropicalmed8040204 - 29 Mar 2023
Viewed by 1664
Abstract
We aimed to estimate the proportion of the population infected with SARS-CoV-2 in the first year of the pandemic. The study population consisted of outpatient adults with mild or no COVID-19 symptoms and was divided into subpopulations with different levels of exposure. Among [...] Read more.
We aimed to estimate the proportion of the population infected with SARS-CoV-2 in the first year of the pandemic. The study population consisted of outpatient adults with mild or no COVID-19 symptoms and was divided into subpopulations with different levels of exposure. Among the subpopulation without known previous COVID-19 contacts, 4143 patients were investigated. Of the subpopulation with known COVID-19 contacts, 594 patients were investigated. IgG- and IgA-seroprevalence and RT-PCR positivity were determined in context with COVID-19 symptoms. Our results suggested no significant age-related differences between participants for IgG positivity but indicated that COVID-19 symptoms occurred most frequently in people aged between 20 and 29 years. Depending on the study population, 23.4–74.0% PCR-positive people (who were symptomless SARS-CoV-2 carriers at the time of the investigation) were identified. It was also observed that 72.7% of the patients remained seronegative for 30 days or more after their first PCR-positive results. This study hoped to contribute to the scientific understanding of the significance of asymptomatic and mild infections in the long persistence of the pandemic. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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19 pages, 2363 KiB  
Article
Dynamics of Antibody Responses after Asymptomatic and Mild to Moderate SARS-CoV-2 Infections: Real-World Data in a Resource-Limited Country
by Naruemit Sayabovorn, Pochamana Phisalprapa, Weerachai Srivanichakorn, Thanet Chaisathaphol, Chaiwat Washirasaksiri, Tullaya Sitasuwan, Rungsima Tinmanee, Chayanis Kositamongkol, Pongpol Nimitpunya, Euarat Mepramoon, Pinyapat Ariyakunaphan, Diana Woradetsittichai, Methee Chayakulkeeree, Pakpoom Phoompoung, Korapat Mayurasakorn, Nitat Sookrung, Anchalee Tungtrongchitr, Rungsima Wanitphakdeedecha, Saipin Muangman, Sansnee Senawong, Watip Tangjittipokin, Gornmigar Sanpawitayakul, Cherdchai Nopmaneejumruslers, Visit Vamvanij and Chonticha Auesomwangadd Show full author list remove Hide full author list
Trop. Med. Infect. Dis. 2023, 8(4), 185; https://doi.org/10.3390/tropicalmed8040185 - 23 Mar 2023
Viewed by 1973
Abstract
The dynamics of humoral immune responses of patients after SARS-CoV-2 infection is unclear. This study prospectively observed changes in anti-receptor binding domain immunoglobulin G (anti-RBD IgG) and neutralizing antibodies against the Wuhan and Delta strains at 1, 3, and 6 months postinfection between [...] Read more.
The dynamics of humoral immune responses of patients after SARS-CoV-2 infection is unclear. This study prospectively observed changes in anti-receptor binding domain immunoglobulin G (anti-RBD IgG) and neutralizing antibodies against the Wuhan and Delta strains at 1, 3, and 6 months postinfection between October 2021 and May 2022. Demographic data, clinical characteristics, baseline parameters, and blood samples of participants were collected. Of 5059 SARS-CoV-2 infected adult patients, only 600 underwent assessment at least once between 3 and 6 months after symptom onset. Patients were categorized as immunocompetent (n = 566), immunocompromised (n = 14), or reinfected (n = 20). A booster dose of a COVID-19 vaccine was strongly associated with maintained or increased COVID-19 antibody levels. The booster dose was also more strongly associated with antibody responses than the primary vaccination series. Among patients receiving a booster dose of a mRNA vaccine or a heterologous regimen, antibody levels remained steady or even increased for 3 to 6 months after symptom onset compared with inactivated or viral vector vaccines. There was a strong correlation between anti-RBD IgG and neutralizing antibodies against the Delta variant. This study is relevant to resource-limited countries for administering COVID-19 vaccines 3 to 6 months after infection. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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15 pages, 1241 KiB  
Article
Comparison of COVID-19 Severity and Mortality Rates in the First Four Epidemic Waves in Hungary in a Single-Center Study with Special Regard to Critically Ill Patients in an Intensive Care Unit
by Éva Nagy, Péter Golopencza, István Barcs and Endre Ludwig
Trop. Med. Infect. Dis. 2023, 8(3), 153; https://doi.org/10.3390/tropicalmed8030153 - 1 Mar 2023
Cited by 2 | Viewed by 1776
Abstract
Different variants of coronavirus 2 (SARS-CoV-2), a virus responsible for severe acute respiratory syndrome, caused several epidemic surges in Hungary. The severity of these surges varied due to the different virulences of the variants. In a single-center, retrospective, observational study, we aimed to [...] Read more.
Different variants of coronavirus 2 (SARS-CoV-2), a virus responsible for severe acute respiratory syndrome, caused several epidemic surges in Hungary. The severity of these surges varied due to the different virulences of the variants. In a single-center, retrospective, observational study, we aimed to assess and compare morbidities and mortality rates across the epidemic waves I to IV with special regard to hospitalized, critically ill patients. A significant difference was found between the surges with regard to morbidity (p < 0.001) and ICU mortality (p = 0.002), while in-hospital mortality rates (p = 0.503) did not differ significantly. Patients under invasive ventilation had a higher incidence of bloodstream infection (aOR: 8.91 [4.43–17.95] p < 0.001), which significantly increased mortality (OR: 3.32 [2.01–5.48]; p < 0.001). Our results suggest that Waves III and IV, caused by the alpha (B.1.1.7) and delta (B.1.617.2) variants, respectively, were more severe in terms of morbidity. The incidence of bloodstream infection was high in critically ill patients. Our results suggest that clinicians should be aware of the risk of bloodstream infection in critically ill ICU patients, especially when invasive ventilation is used. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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10 pages, 420 KiB  
Article
Clinical and Virological Features of SARS-CoV-2 Variants during the Four Waves of the Pandemic in the Mexican Southeast
by Guadalupe del Carmen Baeza-Flores, Juan Pedro Luna-Arias, Jesús Arturo Ruiz-Quiñones, Xavier Miguel Boldo-León, Alberto Cedro-Tanda, Dora Garnica-López, Alfredo Mendoza-Vargas, Jesús M. Magaña-Cerino and Mirian Carolina Martínez-López
Trop. Med. Infect. Dis. 2023, 8(3), 134; https://doi.org/10.3390/tropicalmed8030134 - 23 Feb 2023
Viewed by 1797
Abstract
We conducted a retrospective study using a population of patients who were hospitalized at Dr. Juan Graham Casasus Hospital in Villahermosa (Tabasco, Mexico) and had a positive RT-PCR test for SARS-CoV-2 between June 2020 and January 2022. We analyzed all medical records, including [...] Read more.
We conducted a retrospective study using a population of patients who were hospitalized at Dr. Juan Graham Casasus Hospital in Villahermosa (Tabasco, Mexico) and had a positive RT-PCR test for SARS-CoV-2 between June 2020 and January 2022. We analyzed all medical records, including demographic data, SARS-CoV-2 exposure history, underlying comorbidities, symptoms, signs at admission, laboratory findings during the hospital stay, outcome, and whole-genome sequencing data. Finally, the data were analyzed in different sub-groups according to distribution during waves of the COVID-19 pandemic regarding Mexican reports from June 2020 to January 2022. Of the 200 patients who tested positive via PCR for SARS-CoV-2, only 197 had samples that could be sequenced. Of the samples, 58.9% (n = 116) were males and 41.1% (n = 81) females, with a median age of 61.7 ± 17.0 years. Comparisons between the waves of the pandemic revealed there were significant differences in the fourth wave: the age of patients was higher (p = 0.002); comorbidities such as obesity were lower (p = 0.000), while CKD was higher (p = 0.011); and hospital stays were shorter (p = 0.003). The SARS-CoV-2 sequences revealed the presence of 11 clades in the study population. Overall, we found that adult patients admitted to a third-level Mexican hospital had a wide range of clinical presentations. The current study provides evidence for the simultaneous circulation of SARS-CoV-2 variants during the four pandemic waves. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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12 pages, 1669 KiB  
Article
Cost-Effectiveness Analysis of COVID-19 Vaccine Booster Dose in the Thai Setting during the Period of Omicron Variant Predominance
by Kanchanok Sirison, Natthaprang Nittayasoot, Ranida Techasuwanna, Nisachol Cetthakrikul and Rapeepong Suphanchaimat
Trop. Med. Infect. Dis. 2023, 8(2), 91; https://doi.org/10.3390/tropicalmed8020091 - 30 Jan 2023
Cited by 9 | Viewed by 3484
Abstract
The Thai government implemented COVID-19 booster vaccines to prevent morbidity and mortality during the spreading of the Omicron variant. However, little is known about which types of vaccine should be invested in as the booster dose for the Thai population. This study aims [...] Read more.
The Thai government implemented COVID-19 booster vaccines to prevent morbidity and mortality during the spreading of the Omicron variant. However, little is known about which types of vaccine should be invested in as the booster dose for the Thai population. This study aims to investigate the most cost-effective COVID-19 vaccine for a booster shot as empirical evidence for Thai policymakers. This study applied a stochastic simulation based on a compartmental susceptible-exposed-infectious-recovered model and included system dynamics in the model. We evaluated three scenarios: (1) No booster, (2) A viral vector vaccine as the booster dose, (3) An mRNA vaccine as the booster dose. The incremental cost-effectiveness ratio (ICER) was calculated based on provider perspectives. We found the number of cases in scenarios with viral vector and mRNA booster doses to be lower than in the non-booster group. Likewise, the number of deaths in the viral vector and the mRNA booster scenarios was threefold lower than in the no-booster scenario. Moreover, the estimated grand cost for the no-booster scenario was over 100 billion baht, while viral vector and mRNA scenario costs were 70 and 64.7 billion baht, respectively. ICER shows that viral vector and mRNA scenarios are more cost-effective than the no-booster scenario. Viral vector booster shot appeared to be slightly more cost-effective than mRNA booster shot in terms of death aversion. However, being boosted by an mRNA vaccine seemed slightly more cost-effective than a viral vector vaccine concerning case aversion. In conclusion, policies to promote COVID-19 booster shots in the Thai population by either mRNA or viral vector vaccines are likely to be worthwhile for both economic and public health reasons. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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13 pages, 1038 KiB  
Article
Distinguishing SARS-CoV-2 Infection and Non-SARS-CoV-2 Viral Infections in Adult Patients through Clinical Score Tools
by Rujipas Sirijatuphat, Kulprasut Sirianan, Navin Horthongkham, Chulaluk Komoltri and Nasikarn Angkasekwinai
Trop. Med. Infect. Dis. 2023, 8(1), 61; https://doi.org/10.3390/tropicalmed8010061 - 12 Jan 2023
Viewed by 2721
Abstract
This study aimed to determine distinguishing predictors and develop a clinical score to differentiate COVID-19 and common viral infections (influenza, respiratory syncytial virus (RSV), dengue, chikungunya (CKV), and zika (ZKV)). This retrospective study enrolled 549 adults (100 COVID-19, 100 dengue, 100 influenza, 100 [...] Read more.
This study aimed to determine distinguishing predictors and develop a clinical score to differentiate COVID-19 and common viral infections (influenza, respiratory syncytial virus (RSV), dengue, chikungunya (CKV), and zika (ZKV)). This retrospective study enrolled 549 adults (100 COVID-19, 100 dengue, 100 influenza, 100 RSV, 100 CKV, and 49 ZKV) during the period 2017–2020. CKV and ZKV infections had specific clinical features (i.e., arthralgia and rash); therefore, these diseases were excluded. Multiple binary logistic regression models were fitted to identify significant predictors, and two scores were developed differentiating influenza/RSV from COVID-19 (Flu-RSV/COVID) and dengue from COVID-19 (Dengue/COVID). The five independent predictors of influenza/RSV were age > 50 years, the presence of underlying disease, rhinorrhea, productive sputum, and lymphocyte count < 1000 cell/mm3. Likewise, the five independent predictors of dengue were headache, myalgia, no cough, platelet count < 150,000/mm3, and lymphocyte count < 1000 cell/mm3. The Flu-RSV/COVID score (cut-off value of 4) demonstrated 88% sensitivity and specificity for predicting influenza/RSV (AUROC = 0.94). The Dengue/COVID score (cut-off value of 4) achieved 91% sensitivity and 94% specificity for differentiating dengue and COVID-19 (AUROC = 0.98). The Flu-RSV/COVID and Dengue/COVID scores had a high discriminative ability for differentiating influenza/RSV or dengue infection and COVID-19. The further validation of these scores is needed to ensure their utility in clinical practice. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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8 pages, 1835 KiB  
Opinion
Neurological Diseases Define the Cytokine Profile in CFS during SARS-CoV-2 Infection in Highly Ill Patients
by Lucía Angélica Méndez-García, Helena Solleiro-Villavicencio, Sebastián Guartazaca-Guerrero, Jahir Rodríguez-Morales and José Damián Carrillo-Ruiz
Trop. Med. Infect. Dis. 2023, 8(6), 290; https://doi.org/10.3390/tropicalmed8060290 - 25 May 2023
Cited by 2 | Viewed by 2032
Abstract
Neuroinflammation is critical in developing and progressing neurological diseases. The underlying pro-inflammatory cytokine expression combined with additional mechanisms in the neuropathology, such as oxidative stress, brain–blood barrier damage, and endothelial dysfunction, could contribute to the susceptibility to developing severe COVID-19. The physiopathology of [...] Read more.
Neuroinflammation is critical in developing and progressing neurological diseases. The underlying pro-inflammatory cytokine expression combined with additional mechanisms in the neuropathology, such as oxidative stress, brain–blood barrier damage, and endothelial dysfunction, could contribute to the susceptibility to developing severe COVID-19. The physiopathology of SARS-CoV-2 and other human coronaviruses (H-CoVs) has not been completely understood; however, they have all been linked to a disproportionated response of the immune system, particularly an exacerbated cytokine production and the dysregulation of total cell counts. In this article, based on the compilation of studies reported by our working group regarding COVID-19 and neurological diseases, we propose that the inflammation observed in the central nervous system, through a CSF analysis, could be conditioned by neurological disease(s) and enhanced by COVID-19. Therefore, it is necessary to determine the cytokine profile in different neurological disorders to propose adequate treatments and avoid severe forms of the disease in these patients. Full article
(This article belongs to the Special Issue COVID-19 Variants, Vaccines and New Waves)
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