Safety & effectiveness of COVID-19 vaccines: A narrative review

There are currently eight vaccines against SARS-CoV-2 that have received Emergency Use Authorization by the WHO that can offer some protection to the world's population during the COVID-19 pandemic. Though research is being published all over the world, public health officials, policymakers and governments are collecting evidence-based information to establish the public health policies. Unfortunately, continued international travel, violations of lockdowns and social distancing, the lack of mask use, the emergence of mutant strains of the virus and lower adherence by a sector of the global population that remains sceptical of the protection offered by vaccines, or about any risks associated with vaccines, hamper these efforts. Here we examine the literature on the efficacy, effectiveness and safety of COVID-19 vaccines, with an emphasis on select categories of individuals and against new SARS-CoV-2 strains. The literature shows that these eight vaccines are highly effective in protecting the population from severe disease and death, but there are some issues concerning safety and adverse effects. Further, booster shots and variant-specific vaccines would also be required.

In Vitro Exploration of the Anti-HCV Potential of the Synthetic Spacer Peptides Derived from Human, Bovine, and Camel Lactoferrins

BACKGROUND

Chronic liver disease is often associated with the infection by hepatitis C virus (HCV), which is an enveloped RNA virus belonging to the Flaviviridae family. Many studies found that milk proteins, such as lactoferrin, might have profound antiviral activity against HCV. Various secretory fluids ranging from milk, to tears, saliva, and nasal secretion, and to bile and pancreatic juice, as well as neutrophils, mucosal surfaces, and blood contain a widely spread multifunctional glycoprotein, lactoferrin (Lf), structure of which can be depicted as two homologous domains connected by the short spacer peptide.

OBJECTIVE

This study aimed to understand the effectiveness of the synthetic peptides cLfsp, bLfsp, hLfsp1, and hLfsp2 corresponding to the spacer peptides of camel, bovine, and human Lfs, respectively, against HCV in in vitro settings.

METHOD

We used RT-nested PCR to evaluate the antiviral activity of the synthesized spacer peptides against HCV infectivity in PBMC and HepG2 cells looking at their neutralization, protection, and intracellular treatment potentials.

RESULTS AND CONCLUSION

We show that direct interaction of hLfsp1, hLfsp2, and bLfsp with viral particles is able to neutralize the HCV entry into HepG2 cells (with hLfsp2 being more potent neutralizer than hLfsp1 and bLfsp), whereas cLfsp does not show any neutralizing potential. Therefore, our analysis revealed that different spacer peptides are characterized by different antiviral potentials and use different mechanisms for antiviral protection.