All about Omicron: Transmissibility, Severity, Effectiveness of Previous Infection!!
Researchers in South Africa and around the world are conducting studies to better understand many aspects of Omicron.
It is not yet clear whether Omicron is more transmissible (e.g., more easily spread from person to person) compared to other variants, including Delta. The number of people testing positive has risen in areas of South Africa affected by this variant, but it is yet to conclude if it is because of Omicron or other factors.
Severity of disease:
It is not yet clear whether infection with Omicron causes more severe disease compared to infections with other variants, including Delta. There is currently no information to suggest that symptoms associated with Omicron are different from those from other variants. All variants of COVID-19, including the Delta variant that is dominant worldwide, can cause severe disease or death, in particular for the most vulnerable people, and thus prevention is always key.
Effectiveness of prior infection
Preliminary evidence suggests there may be an increased risk of reinfection with Omicron (ie, people who have previously had COVID-19 could become reinfected more easily with Omicron), as compared to other variants of concern, but information is limited. More information on this will become available in the coming days and weeks.
Effectiveness of vaccines: WHO is working with technical partners to understand the potential impact of this variant on our existing countermeasures, including vaccines. Vaccines remain critical to reducing severe disease and death, including against the dominant circulating variant, Delta. Current vaccines remain effective against severe disease and death.
Effectiveness of current tests: The widely used PCR tests continue to detect infection, including infection with Omicron, as we have seen with other variants as well. Studies are ongoing to determine whether there is any impact on other types of tests, including rapid antigen detection tests.
Effectiveness of current treatments: Corticosteroids and IL6 Receptor Blockers will still be effective for managing patients with severe COVID-19. Other treatments will be assessed to see if they are still as effective given the changes to parts of the virus in the Omicron variant.
WHO Recommended actions for countries
As Omicron has been designated a Variant of Concern, there are several actions WHO recommends countries to undertake, including enhancing surveillance and sequencing of cases; sharing genome sequences on publicly available databases, such as GISAID; reporting initial cases or clusters to WHO; performing field investigations and laboratory assessments to better understand if Omicron has different transmission or disease characteristics, or impacts effectiveness of vaccines, therapeutics, diagnostics or public health and social measures.
Countries should continue to implement the effective public health measures to reduce COVID-19 circulation overall, using a risk analysis and science-based approach. They should increase some public health and medical capacities to manage an increase in cases. WHO is providing countries with support and guidance for both readiness and response.
In addition, it is vitally important that inequities in access to COVID-19 vaccines are urgently addressed to ensure that vulnerable groups everywhere, including health workers and older persons, receive their first and second doses, alongside equitable access to treatment and diagnostics.
WHO Recommended actions for people
The most effective steps individuals can take to reduce the spread of the COVID-19 virus is to keep a physical distance of at least 1 metre from others; wear a well-fitting mask; open windows to improve ventilation; avoid poorly ventilated or crowded spaces; keep hands clean; cough or sneeze into a bent elbow or tissue; and get vaccinated when it’s their turn.
Inputs from WHO.int