Hepatoprotective and cardioprotective effect of Artemisia nilagirica leaf extract on E. coli challenged broiler chicken

Artemisia nilagirica is an important medicinal plant found to exhibit several medicinal properties but the use of its leaves for combating E. coli infection has not been scientifically validated in poultry. The present study was conducted to evaluate the protective effects of methanol leaf extract of A. nilagirica (ANE) on E. coli challenged broiler chickens. Three hundred and thirty, day-old broiler chickens, were divided into 6 groups of 55 each, with group EX infected intraperitoneally (I/P) with LD50 dose of 1 × 107 cfu/ml of E. coli; group(s) EA1, EA2 and EA3 infected I/P with 1 × 107 cfu/ml of E. coli and supplemented with ANE @ 0.5, 1.0 and 2.0 g/L of drinking water, respectively; group AX were only given ANE @ 2.0 g/L in the drinking water. ANE treatment was started from day 4 and was continuously given in the drinking water up to day 21. E. coli infection was given to the birds on day 7 of their age. The effect of the plant extract was evaluated on the basis of gross, microscopic and ultrastructural alterations in E. coli challenged broiler chickens. The extract of A. nilagirica was found to show antibacterial, cardioprotective and hepatoprotective properties in a dose-dependent manner on the basis of gross and microscopic examination. The methanol extract of A. nilagirica leaves revealed no toxic effect on the hepatocytes on ultrastructural evaluation. This study demonstrates the antimicrobial, hepatoprotective and cardioprotective activities of ANE in broiler chickens infected with E. coli organism.

Pathomolecular epidemiology, antimicrobial resistance, and virulence genes of Streptococcus dysgalactiae subsp. equisimilis isolates from slaughtered pigs in India

AIMS

We aimed to investigate the prevalence, pathology, and characterization of Streptococcus dysgalactiae subsp. equisimilis (SDSE) in slaughtered pigs of India.

METHODS AND RESULTS

We collected 1254 morbid tissues (lungs-627 and spleen-627) and 627 heart-blood from 627 slaughtered pigs. The bacterial isolation, antibiogram, virulence gene profiling, and mouse pathogenicity testing were performed for the detection and characterization of SDSE. A total of 177 isolates (heart-blood-160 and tissues-17) were recovered from 627 slaughtered pigs with higher isolation rate in heart-blood (25.51%). The prevalence of SDSE was 11% in morbid tissues by polymerase chain reaction. Majority of isolates showed higher detection of streptolysin O, followed by streptokinase and extracellular phospholipase A virulence genes with higher degree of resistance to azithromycin, clindamycin, erythromycin, and penicillin antibiotics. Mouse pathogenicity testing confirmed virulence based on histopathological lesions and re-isolation of SDSE.

CONCLUSIONS

Our findings highlight the high prevalence of SDSE in slaughtered pigs. The presence of virulence genes and mouse pathogenicity testing confirm their pathogenic potential.

Development of Hemagglutinin-Neuraminidase Homologous Peptides as Novel Promising Therapeutic Agents Against Peste des Petits Ruminants Virus

The lack of specific antiviral therapy and complications associated with the existing peste des petits ruminants (PPR) vaccines accentuates the search of novel antiviral blocking agents in order to curtail the PPR infection at initial level. The synthetic hemagglutinin-neuraminidase (HN) homologous peptides may compete with the natural HN protein of PPR virus for binding to signaling lymphocytic activation molecule (SLAM) receptor, consequently, may disrupt peste des petits ruminants virus (PPRV) at entry level. Therefore, insilico analysis, synthesis, purification and subsequent characterization of HN homologous peptides were conducted in this study. The HN homologous peptides were synthesized by means of solid phase chemistry and were purified by reversed-phase-high performance liquid chromatography. The mass as well as sequence of HN homologous peptides were assessed by mass spectroscopy while its secondary structure was elucidated by circular dichroism spectroscopy. The binding (interaction) efficacy of HN homologous peptides with PPRV antibodies was assessed via indirect enzyme linked immunosorbent assay, visual detection test (red wine to purple), bathochromic shift under UV-Vis spectrophotometry and lateral flow immunochromatographic strip test. The antiviral properties and cytotoxicity of these peptides were also assessed in B95a cell line with changes in cytopathic effect and titer of PPRV (Sungri/96). The presence of green fluorescein isothiocyanate over the B95a cell surface pointed towards the binding of HN homologous peptides with surface SLAM receptor. Moreover, the intact beta sheet configuration in water and lower cytotoxicity [cytotoxic concentration 50 (CC50) > 1000 µg/ml] of these peptides signifies its in vivo use. Among HN homologous peptides, the binding efficacy and antiviral properties of pep A was relatively high in comparison to pep B and Pep ppr peptides. The prerequisite concentration of HN homologous peptides (pep A = 12.5 µg/ml; pep B = 25 µg/ml; pep ppr = 25 µg/ml) to exemplify its antiviral effect was much lower than its CC50 level. Hence, this study signifies the therapeutic potential of synthetic HN homologous peptides.

Mpox vaccination in global perspective: priorities and challenges

After the global panic created by COVID-19, the monkeypox (Mpox) virus emerged as a new challenge for the world population. As of 19 January 2023, a total of 84,733 cases across 110 countries/territories including 80 deaths has been reported. The virus has been transmitted to nonendemic countries in a short span of 6 months warranting WHO to declare Mpox, a Public Health Emergency of International Concern on 23 July 2022. As the Mpox virus is crossing geographical boundaries without established transmission patterns, there is an urgent need for new scientific strategies from global researchers to contain it before turning into the next pandemic. The control of Mpox outbreaks primarily relies on various public health measures such as proper surveillance, contact tracing, rapid diagnosis, isolation and care of patients, and vaccination. At present, there are three vaccines viz. ACAM2000, MVABN, and LC16 are in consideration and have been approved in several jurisdictions for ongoing Mpox outbreak. Prioritization of individuals along with the production of specific Mpox vaccine is need of the hour to meet out the global demand of Mpox vaccination.

Viral spillover to humans: could Langya (LayV) virus cause a pandemic?

Decades have been witnessing clusters of zoonotic diseases. Human beings at the peak of evolution should not be empowered to alter the environmental homeostasis. Primitive organisms are more rooted to mutate and adapt as per the need or turmoil. Once humans come in the vicinity of these organisms normally residing in their native niche, nature has to pay the cost. Disease outbreaks mostly caused due to unnecessary anthropogenic activities. The threat is that the repercussions are taken for granted or hided wreaking havoc in developing and developed economies leading to an outbreak, an epidemic or a pandemic. The worst influenza outbreak in the world was the 1918 flu that killed nearly 50 million people around the world and modern strains still have an annual death toll in thousands, so the flu is no trifling matter even in a world still facing SARS-CoV-2. Recently, researchers estimated the expected yearly cost of pandemic influenza at roughly $500 billion (0.6 percent of global income), including both lost income and the intrinsic cost of elevated mortality.1.

Pathomorphology, immunohistochemical, and molecular detection of an atypical porcine dermatitis and nephropathy syndrome (PDNS) due to PCV-2d-2 in naturally affected grower pigs of India

Porcine circovirus type 2 (PCV-2) is of great economic significance to porcine industry worldwide. PCV-2 variants and genotypes, alternating world over, are the etiological agent of several clinical syndromes such as porcine dermatitis and nephropathy syndrome (PDNS), post-weaning multi-systemic wasting syndrome (PMWS) and others in pigs. This study is reporting an atypical manifestation of PDNS in twelve grower pigs, 3- to - 4.5 months age and either sex, died of the disease, with predominant lesions of nephropathy and no obvious clinical lesions in skin. Necropsy examination of pigs showed lesions of petechial -to- ecchymotic hemorrhages in the kidneys and in the right auricular musculature of the hearts. Microscopic lesions in H & E sections of the kidneys showed acute glomerulonephritis, interstitial nephritis, and vasculitis, but the skin morphology and architecture remained unaltered in contrast to the pathognomonic lesions of PDNS described in the literature. Other syndromic associations of PDNS in these cases included-perimyocarditis, interstitial pneumonia, depleted lymphoid tissues, tonsillitis, enteritis, and meningo-encephalitis. The lesional sites in duplicate paraffin tissue sections of kidneys, heart, lungs, spleen, lymph nodes, intestine, and brain demonstrated PCV-2 antigen in the cytoplasm of cells as highlighted by the intense immunolabeling on IHC staining. The PCV-2 positive organs reconfirmed by PCR, targeting ORF2 gene, which yielded 481bp size of products. The sequencing results of 481bp products on phylogenetic analysis showed 94% similarity with that of PCV-2 sequences in the database that grouped into PCV2d-2 genotype. The present report confirms, probably for the first time, the atypical PDNS cases due to PCV2d-2 genotype in naturally affected grower pigs of India.

Detection of porcine enteric picornaviruses from faecal samples of Indian pigs

Porcine enteric picornaviruses often consequence diarrhoea and nervous complications in pig and pose enormous loss to pig farming. The present study expands the limited Indian data of porcine enteric picornaviruses which is needed for the early implementation of control measures and to check further outbreaks. A total of 398 porcine faecal samples from Uttar Pradesh, Madhya Pradesh, Chhattisgarh and Jharkhand state of India were screened for porcine teschovirus (PTV), porcine sapelovirus (PSV) and enterovirus G (EV-G) by reverse transcriptase-polymerase chain reaction (RT-PCR) using 5'UTR-specific primers. The prevalence of PTV, PSV and EV-G was found to be 12.81% (51/398), 5.77% (23/398) and 24.37% (97/398), respectively. EV-G was relatively higher in circulation in Indian pigs among all the included enteric picornaviruses. Conversely, the concurrent infection of more than one enteric picornavirus was also frequent.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13337-022-00756-0.

Exploration of antigenic determinants in spike glycoprotein of SARS-CoV2 and identification of five salient potential epitopes

Emerging pathogens have been an eternal threat to mankind. In a series of pandemics caused by notorious coronaviruses, a newly emerged SARS-CoV2 virus is creating panic among the world population. The unavailability of reliable theranostics insists the exploration of antigenic determinants in spike glycoprotein of SARS-CoV2. The four novel inserts ('70VSGTNGT76', '150KSWM153', 247SYLTPG252 and 674QTQTNSPRR682) in SARS-CoV2 spike protein were unraveled via multiple sequence alignment of spike proteins of SARS-CoV2, SARS-CoV, and MERS-CoV. The three-dimension (3D) modeling of the spike protein of the SARS-CoV2 and their interaction with the ACE2 receptor was delineated with the help of SWISS-MODEL and 3DLigandSite web servers. The predicted 3D model of SARS-CoV2 was further verified by SAVES, RAMPAGE, and ProSA-web tools. The potential B-cell immunogenic epitopes of SARS-CoV2 were predicted out by using various software viz. IEDB B-cell epitopes prediction tool, BepiPred linear epitope prediction tool, Emini Surface Accessibility Prediction tool, and Kolaskar-Tongaonkar antigenicity web tool. The five epitopes (i.e. '71SGTNGTKRFDN81, 247SYLTPG252, 634RVYST638, 675QTQTNSPRRARSV687, and 1054QSAPH1058) were selected as potent antigenic determinants. The quantum of information generated by this study will prove beneficial for the development of effective therapeutics, diagnostics, and multi-epitopic vaccines to combat this ongoing menace.

No dynamic changes in plasma ACE2 activity in patients with acute coronary syndrome

Background

Angiotensin converting enzyme 2 (ACE2) is expressed in the human myocardium and blood vessels and degrades the vasoconstrictor peptide angiotensin (Ang) II. Plasma ACE2 activity is elevated in patients with cardiovascular disease (CVD) and is a predictor of major adverse cardiovascular events (MACE) in obstructive coronary artery disease. However, it is unknown whether acute coronary syndrome (ACS) causes dynamic changes in plasma ACE2 activity.

Purpose

We investigated dynamic changes in serial troponin-T and plasma ACE2 activity in patients presenting with ACS who underwent invasive coronary angiography (ICA).

Methods

Consecutive patients admitted with ACS from October-November 2019 were screened. Those meeting the Fourth Universal Definition of Myocardial Infarction who had both ICA and serial troponin-T testing were included. The study was approved by the hospitals Human Research Ethics Committee. All patients had routine plasma samples taken over 3 time-points for measurement of troponin-T; the same sample was used to measure plasma ACE2 activity. Catalytic ACE2 activity was measured using a validated, sensitive quenched fluorescent substrate-based assay. Serial median troponin and ACE2 activity levels were analysed using the Friedman test for repeated measures.

Results

Forty-nine patients were included. The mean age of participants was 63.9±11.0 years, and 36 (74%) patients were male. Overall, 16 (36%) patients presented with ST-elevation myocardial infarction (STEMI) and 29 (74%) with non-ST-elevation myocardial infarction (NSTEMI). Twenty-nine (59%) patients had a history of hypertension and 14 (29%) a history of ischaemic heart disease; 13 (27%) with priorMI, 11 (22%) had previous PCI and 2 (4%) had prior coronary artery bypass grafting. Over the 3 time points, there was a clear rise in median troponin-T levels representing myocardial injury (p<0.001), with no change in median plasma ACE2 activity (p=0.23, table 1). There was no difference in median ACE2 activity in those presenting with STEMI vs. NSTEMI (6.9 [2.1–9.5] vs. 6.0 [1.8–12.1], p=0.87), nor in those who underwent PCI to a culprit lesion compared to those who did not have a culprit lesion stented (5.8 [0.9–10.5] vs. 7.3 [2.8–14.9], p=0.37).

Conclusions

Patients with ACS had higher plasma ACE2 levels compared to levels previously reported in healthy controls. There were no dynamic changes in ACE2 activity in the setting of ACS, despite a significant rise in troponin-T. These results suggest that plasma ACE2 levels reflect underlying endothelial dysfunction rather than acute myocardial injury or infarction. Studies are now underway to assess if plasma ACE2 activity in ACS predicts MACE.

Funding Acknowledgement

Type of funding sources: None. Table 1

SARS-CoV-2 infection during pregnancy and pregnancy-related conditions: Concerns, challenges, management and mitigation strategies-a narrative review

The ongoing coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global public health problem. The SARS-CoV-2 triggers hyper-activation of inflammatory and immune responses resulting in cytokine storm and increased inflammatory responses on several organs like lungs, kidneys, intestine, and placenta. Although SARS-CoV-2 affects individuals of all age groups and physiological statuses, immune-compromised individuals such as pregnant women are considered as a highly vulnerable group. This review aims to raise the concerns of high risk of infection, morbidity and mortality of COVID-19 in pregnant women and provides critical reviews of pathophysiology and pathobiology of how SARS-CoV-2 infection potentially increases the severity and fatality during pregnancy. This article also provides a discussion of current evidence on vertical transmission of SARS-CoV-2 during pregnancy and breastfeeding. Lastly, guidelines on management, treatment, preventive, and mitigation strategies of SARS-CoV-2 infection during pregnancy and pregnancy-related conditions such as delivery and breastfeeding are discussed.

The role of disinfectants and sanitizers during COVID-19 pandemic: advantages and deleterious effects on humans and the environment

Disinfectants and sanitizers are essential preventive agents against the coronavirus disease 2019 (COVID-19) pandemic; however, the pandemic crisis was marred by undue hype, which led to the indiscriminate use of disinfectants and sanitizers. Despite demonstrating a beneficial role in the control and prevention of COVID-19, there are crucial concerns regarding the large-scale use of disinfectants and sanitizers, including the side effects on human and animal health along with harmful impacts exerted on the environment and ecological balance. This article discusses the roles of disinfectants and sanitizers in the control and prevention of the current pandemic and highlights updated disinfection techniques against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This article provides evidence of the deleterious effects of disinfectants and sanitizers exerted on humans, animals, and the environment as well as suggests mitigation strategies to reduce these effects. Additionally, potential technologies and approaches for the reduction of these effects and the development of safe, affordable, and effective disinfectants are discussed, particularly, eco-friendly technologies using nanotechnology and nanomedicine.

Advances in therapeutic and managemental approaches of bovine mastitis: a comprehensive review

Mastitis (intramammary inflammation) caused by infectious pathogens is still considered a devastating condition of dairy animals affecting animal welfare as well as economically incurring huge losses to the dairy industry by means of decreased production performance and increased culling rates. Bovine mastitis is the inflammation of the mammary glands/udder of bovines, caused by bacterial pathogens, in most cases. Routine diagnosis is based on clinical and subclinical forms of the disease. This underlines the significance of early and rapid identification/detection of etiological agents at the farm level, for which several diagnostic techniques have been developed. Therapeutic regimens such as antibiotics, immunotherapy, bacteriocins, bacteriophages, antimicrobial peptides, probiotics, stem cell therapy, native secretory factors, nutritional, dry cow and lactation therapy, genetic selection, herbs, and nanoparticle technology-based therapy have been evaluated for their efficacy in the treatment of mastitis. Even though several strategies have been developed over the years for the purpose of managing both clinical and subclinical forms of mastitis, all of them lacked the efficacy to eliminate the associated etiological agent when used as a monotherapy. Further, research has to be directed towards the development of new therapeutic agents/techniques that can both replace conventional techniques and also solve the problem of emerging antibiotic resistance. The objective of the present review is to describe the etiological agents, pathogenesis, and diagnosis in brief along with an extensive discussion on the advances in the treatment and management of mastitis, which would help safeguard the health of dairy animals.

Bovine brucellosis - a comprehensive review

Brucellosis is a zoonotic disease of great animal welfare and economic implications worldwide known since ancient times. The emergence of brucellosis in new areas as well as transmission of brucellosis from wild and domestic animals is of great significance in terms of new epidemiological dimensions. Brucellosis poses a major public health threat by the consumption of non-pasteurized milk and milk products produced by unhygienic dairy farms in endemic areas. Regular and meticulous surveillance is essentially required to determine the true picture of brucellosis especially in areas with continuous high prevalence. Additionally, international migration of humans, animals and trade of animal products has created a challenge for disease spread and diagnosis in non-endemic areas. Isolation and identification remain the gold standard test, which requires expertise. The advancement in diagnostic strategies coupled with screening of newly introduced animals is warranted to control the disease. Of note, the diagnostic value of miRNAs for appropriate detection of B. abortus infection has been shown. The most widely used vaccine strains to protect against Brucella infection and related abortions in cattle are strain 19 and RB51. Moreover, it is very important to note that no vaccine, which is highly protective, safe and effective is available either for bovines or human beings. Research results encourage the use of bacteriophage lysates in treatment of bovine brucellosis. One Health approach can aid in control of this disease, both in animals and man.

Medical Care Disruptions During the First Six-Months of the COVID19 Pandemic: The Experience of Older Breast Cancer Survivors

Purpose.

Older cancer survivors required medical care during the COVID-19 pandemic despite infection risks, but there are limited data on medical care in this age group.

Methods.

We evaluated care disruptions in a longitudinal cohort of non-metastatic breast cancer survivors ages 60–98 from five US regions (n=321). Survivors completed a web-based or telephone survey from May 27, 2020 to September 11, 2020. Care disruptions included self-reported interruptions in ability to see doctors, receive treatment or supportive therapies, or fill prescriptions. Logistic regression models evaluated bivariate and multivariate associations between care disruptions and education, medical, psychosocial and COVID-19-related factors. Multivariate models included age, county COVID-19 rates, comorbidity and post-diagnosis time.

Results.

There was a high response rate (n=262, 81.6%). Survivors were 32.2 months post-diagnosis (SD 17.5, range 4–73). Nearly half (48%) reported a medical disruption. The unadjusted odds of care disruptions were significantly higher with more education (OR 1.23 per one-year increase, 95% CI 1.09–1.39, p =0.001) and greater depression (OR 1.04 per one-point increase in CES-D score, CI 1.003–1.08, p=0.033); tangible support decreased the odds of disruptions (OR 0.99, 95% CI 0.97–0.99 per one-point increase, p=0.012). There was a trend for associations between disruptions and comorbidity (unadjusted OR 1.13 per 1 added comorbidity, 95% CI 0.99–1.29, p=0.07). Adjusting for covariates, only higher education (p=0.001) and tangible social support (p=0.006) remained significantly associated with having care disruptions.

Conclusions.

Older breast cancer survivors reported high rates of medical care disruptions during the COVID-19 pandemic and psychosocial factors were associated with care disruptions.

Physiological implications of COVID-19 in reproduction: angiotensin-converting enzyme 2 a key player

The COVID-19 outbreak, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), was first identified in China, and it has quickly become a global threat to public health due to its rapid rate of transmission and fatalities. Angiotensin-converting enzyme 2 (ACE2) has been identified as a receptor that mediates the entry of SARS-CoV-2 into human cells, as in the case of severe acute respiratory syndrome coronavirus (SARS-CoV). Several studies have reported that ACE2 expression is higher in Leydig, Sertoli and seminiferous ductal cells of males, as well as in ovarian follicle cells of females, suggesting possible potential pathogenicity of the coronavirus in the reproductive system. Higher ACE2 expression in the human placenta and reports of vertical transmission of SARS-CoV-2 among clinical cases have increased the relevance of further studies in this area. This review focuses on the interaction between SARS-CoV-2 and the ACE2 receptor and speculates on the mechanistic interplay in association with male and female reproductive physiology. In addition, based on the available literature, we discuss the alleged sex differences in terms of the infectivity of SARS-CoV-2, which is claimed greater among males, and further explore the physiological role of ACE2 and 17β-oestradiol for the same.

SARS-CoV-2 existence in sewage and wastewater: A global public health concern?

The SARS-CoV-2/COVID-19 pandemic has spread across the globe and affected millions of individuals as of the efficient virus transmission potential mediated via multiple virus shedding routes. The presence of SARS-CoV-2 in the stool samples and its prolonged shedding in environmental compartments like sewage and wastewater signifies a potential threat adding to the transmission cycle of this novel virus. The potential role played by the asymptomatic COVID-19 patients in transmitting the disease via the fecal-oral route is now under investigation. Hence, in the present scenario, wastewater-based epidemiology, and sewage surveillance may provide valuable insights into the prevalence of SARS-CoV-2 among the human population and could serve as a sensitive surveillance system and a crucial early warning tool. Further studies are required to determine the survival of SARS-CoV-2 in the environment, transmissibility through wastewater, and the potential to infect humans via the fecal-oral route. Appropriate frameworks with regards to evaluation and analysis of SARS-CoV-2 will help implement appropriate intervention strategies and necessary sanitation practices to ensure virus free clean water supply to have a check on the further spread of this pandemic virus.

MERS-CoV: epidemiology, molecular dynamics, therapeutics, and future challenges

The Severe Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has gained research attention worldwide, given the current pandemic. Nevertheless, a previous zoonotic and highly pathogenic coronavirus, the Middle East Respiratory Syndrome coronavirus (MERS-CoV), is still causing concern, especially in Saudi Arabia and neighbour countries. The MERS-CoV has been reported from respiratory samples in more than 27 countries, and around 2500 cases have been reported with an approximate fatality rate of 35%. After its emergence in 2012 intermittent, sporadic cases, nosocomial infections and many community clusters of MERS continued to occur in many countries. Human-to-human transmission resulted in the large outbreaks in Saudi Arabia. The inherent genetic variability among various clads of the MERS-CoV might have probably paved the events of cross-species transmission along with changes in the inter-species and intra-species tropism. The current review is drafted using an extensive review of literature on various databases, selecting of publications irrespective of favouring or opposing, assessing the merit of study, the abstraction of data and analysing data. The genome of MERS-CoV contains around thirty thousand nucleotides having seven predicted open reading frames. Spike (S), envelope (E), membrane (M), and nucleocapsid (N) proteins are the four main structural proteins. The surface located spike protein (S) of betacoronaviruses has been established to be one of the significant factors in their zoonotic transmission through virus-receptor recognition mediation and subsequent initiation of viral infection. Three regions in Saudi Arabia (KSA), Eastern Province, Riyadh and Makkah were affected severely. The epidemic progression had been the highest in 2014 in Makkah and Riyadh and Eastern Province in 2013. With a lurking epidemic scare, there is a crucial need for effective therapeutic and immunological remedies constructed on sound molecular investigations.

COVID-19 in the elderly people and advances in vaccination approaches

The rapid worldwide spread of the COVID-19 pandemic, caused by the newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in tens of millions of infections and over one million deaths. SARS-CoV-2 infection affects all age groups; however, those over 60 years old are affected more severely. Moreover, pre-existing co-morbidities result in higher COVID-19-associated mortality in the geriatric population. This article highlights the associated risk factors of SARS-CoV-2 infection in older people and progress in developing COVID-19 vaccines, especially for efficient vaccination of the older population. There is also a summary of immunomodulatory and immunotherapeutic approaches to ameliorate the outcome of COVID-19 in older individuals.

COVID-19 - Recent advancements in identifying novel vaccine candidates and current status of upcoming SARS-CoV-2 vaccines

The COVID-19 pandemic caused by SARS-CoV-2 has spread rapidly. To date, countries have relied on the prevention of the disease through isolation, quarantine, and clinical care of affected individuals. However, studies on the roles of asymptomatic and mildly infected subjects in disease transmission, use of antiviral drugs, and vaccination of the general population will be very important for mitigating the effects of the eventual return of this pandemic. Initial investigations are ongoing to evaluate antigenic structures of SARS-CoV-2 and the immunogenicity of vaccine candidates. There also is a need to comprehensively compile the details of previous studies on SARS-related vaccines that can be extrapolated to identify potent vaccine targets for developing COVID-19 vaccines. This review aims to analyze previous studies, current status, and future possibilities for producing SARS-CoV-2 vaccines.