Table Info

Table 1.

SARS-CoV-2 variants and associated symptoms, emergence periods, and vaccination

Variant	Neurological symptoms	Vestibular symptoms	Othorhinolaryngological symptoms	Vaccine introduction and effectiveness	Period of emergence
Alpha (B.1.1.7)	Headache Brain fog	Dizziness	Loss of taste/smell Sore throat	December 2020 (first detected in the UK)	Vaccines were introduced in December 2020. Moderate reduction in neutralization for Moderna and Novavax vaccines compared to the original strain.
Beta (B.1.351)	Headache Fatigue Cognitive issues	Dizziness (rare)	Nasal congestion Sore throat	Late 2020 (first detected in South Africa)	Pfizer vaccine showed reduced neutralization. Covaxin demonstrated significant neutralization.
Gamma (P.1)	Anxiety Depression Headache	Dizziness	Prolonged loss of taste/smell Nasal congestion	Late 2020 (first detected in travelers from Brazil in Japan)	Reduced neutralization observed with Pfizer-BioNTech and Moderna vaccines.
Delta (B.1.617.2)	Severe headache Confusion	Dizziness (rare)	Severe sore throat Ear pain Reduced loss of smell	Late 2021 (first detected in India)	Pfizer and Moderna vaccines showed reduced immune response due to L452R mutation. Improved transmissibility linked to spike protein mutations.
Omicron (BA.1, BA.2, BA.4, BA.5)	Mental fatigue Brain fog	Dizziness (less common)	Predominant sore throat Less frequent loss of taste/smell	Late 2021 (first detected in multiple regions)	Vaccines and prior immunity appear to mitigate the severe effects. Less anosmia due to differences. In cellular tropism and reduced inflammatory dysregulation.
Omicron (XBB, BQ.1)	Headache Brain fog Peripheral neuropathy	Dizziness (less common)	Dominant nasal symptoms Dry cough	Late 2022 (first detected in multiple regions)	Updated booster vaccines were introduced in mid-2022 to target Omicron subvariants.

Declarations

Author contributions

WAR: Conceptualization, Investigation, Writing—original draft, Writing—review & editing. CB: Conceptualization, Writing—original draft, Writing—review & editing, Supervision. AM: Conceptualization, Validation, Writing—review & editing, Supervision. All authors read and approved the submitted version.

Conflicts of interest

The authors declare that they have no conflicts of interest.

Ethical approval

This study was approved by the Sapienza University of Rome Hospital Ethical Committee (Ref. 6536), and all the study procedures followed the Helsinki Declaration of 2013, for human rights and experimentation.

Consent to participate

Informed consent was not needed due to the retrospective nature of this study.

Consent to publication

Not required.

Availability of data and materials

The datasets that support the findings of this study are available from the corresponding author on reasonable request.

Funding

We acknowledge financial support under the National Recovery and Resilience Plan (NRRP), Mission 4, Component 2, Investment 1.1, Call for tender No. 104 published on 2.2.2022 by the Italian Ministry of University and Research (MUR), funded by the European Union—NextGenerationEU—Project Title—Mapping NEUROCOVID via neurobiology and neurovolatilome in Post-COVID-19 patients—CUP B53D23018450006—Grant Assignment Decree No. 1110 adopted on 20 July 2023 by the Italian Ministry of Ministry of University and Research (MUR). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Copyright

Publisher’s note

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