10 Dec 2021

COVID-19: variants of concern

Advice for travellers and health professionals COVID-19: variants of concern

All viruses, including SARS-CoV-2, the virus that causes COVID-19, change over time. Most changes have little to no impact. However, some changes may affect the virus’s properties, such as how easily it spreads, the associated disease severity, or the performance of vaccines, therapeutic medicines, diagnostic tools, or other public health and social measures [1].

The emergence of variants that pose increased risk to global public health has resulted in some being designated as ‘Variants of Interest’ (VOIs) and ‘Variants of Concern’ (VOCs). This allows prioritisation in terms of global monitoring and research, and ultimately to inform the ongoing response to the COVID-19 pandemic [1].

VOCs are usually variants showing evidence of an increase in transmissibility, more severe disease, or significant reduction in effectiveness of treatments, vaccines, or diagnostic tests [2].

As well as scientific names, in the spring of 2021, the World Health Organization (WHO) assigned simpler labels for VOIs and VOCs using the letters of the Greek alphabet [Alpha, Beta, Gamma, Delta etc.] [3].

Several VOCs are circulating worldwide; this includes Alpha, Beta, Gamma and Delta variants. Of these the Delta variant is currently dominant worldwide [4]. In November 2021, a new VOC (Omicron or B.1.1.529) was identified in South Africa and other southern African countries. Other countries throughout the world, including the United Kingdom, have since reported cases [4]. The public health response to the Omicron variant has been cautious; early laboratory studies suggested that it could spread easily and that vaccines might be less effective against it. More information on how the Omicron variant affects people is being collected and evaluated [5].

COVID-19 vaccines used in the UK are effective at preventing COVID-19 disease including COVID-19 illness caused by the Delta variant and are highly effective against hospitalisation and death [6,7]. Although it is not known to what extent available COVID-19 vaccines might protect against the Omicron variant, to optimise individual protection, the Joint Committee on Vaccination and Immunisation (JCVI) has expanded the list of those eligible for booster vaccinations, as well as reiterating the importance of primary COVID-19 vaccination for all who are eligible [8].

As well as public health measures already in place in many countries, enhanced or additional measures for travellers arriving from areas known to be affected by the Omicron variant are being implemented in many countries. These include changes in requirements of proof of vaccination, testing and quarantine or self- isolation [9].

Advice for travellers

Ensure you are up to date with your COVID-19 vaccination courses, including booster doses as recommended in the UK vaccination programme. Completing the vaccination schedule according to JCVI recommendations will ensure you have the best chance of protection against COVID-19 infection.

You should check Foreign, Commonwealth & Development Office travel advice and carefully consider your personal situation and risks of COVID-19 before travel. The risk of COVID-19, public health policy and travel advice or restrictions may change quickly particularly when a new VOC is identified. Therefore make sure you have access to up-to-date information on COVID-19 and be prepared for rapid changes in guidance both before and during travel. This is particularly important if you are at higher risk from COVID-19.

If you choose to travel, be prepared for the possibility of disruption to your plans, and consider the potential impact of these on your finances and travel insurance. Remember that UK entry and quarantine rules can change at short notice, including additions to Red List countries during this continuing pandemic.

In addition, while abroad, you should remember to wash your hands, cover your face, make space. These are the three most effective ways we can all control the spread of the virus. In particular:

  • Avoid contact with anyone who is unwell
  • Avoid touching eyes, nose, and mouth with unwashed hands
  • Wash hands frequently with soap and running water for at least 20 seconds
  • Use alcohol-based hand sanitiser (60% alcohol or above) if soap and water unavailable
  • Clean and disinfect frequently touched objects/surfaces
  • Consider wearing face coverings even if not mandated; Face coverings are likely to be required in some situations including airports and public transport
  • Follow travel requirements, social distancing guidelines and local rules at destination
  • Open windows/doors to let fresh air in when sharing space with others

More advice is available here: COVID-19: general advice for travellers.


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