Bogotá, January 24, 2022. The spread of the worrying variants of the SARS-CoV-2 virus has been a major challenge worldwide. The last of these variants to appear is B.1.1.529, which was first identified on November 9, 2021, and given the name Omicron. The number of COVID-19 cases has henceforth spiked considerably globally.
"Due to the behavior of this variant that is highly contagious–never before observed during the pandemic–, it is clear that it is necessary to adapt response measures promptly, and this includes making adjustments to national vaccination plans. Several countries have understood this as well," explained Julián Fernández, director of Epidemiology and Demography of the Ministry of Health and Social Protection.
Studies to date have shown that vaccines remain effective in preventing severe forms of Omicron. However, due to the behavior of the variant, it is necessary to take measures to avoid potential undesirable impacts on the health system, given the high level of transmission of this variant, which can especially affect the high demand or the health personnel. Also, considering that although the probability of complications from this variant is lower than with previous variants, it can seriously impact some people, especially those who are not vaccinated or present risk factors.
Due to the above, the possibility of administering COVID-19 booster doses was made available for people four months after completing their initial schedule. This decision was based on the evidence of decreased immunity, the current hyper-contagion, and the high effectiveness of the booster dose.
Taking into account that Omicron is a highly transmissible variant, representing a very important contagion rate and shorter incubation periods, it has resulted in a sharp escalation in cases in the countries where it has landed and more quickly than the previous concerning variants. This phenomenon is already being observed in Colombia in some regions.
"The effectiveness to prevent contagion of the available vaccines is lower for the Omicron variant. However, available evidence suggests that this effectiveness is regained with the booster dose. Therefore, increasing coverage with the administration of the booster doses in the population aged 18 and over would not only reduce the incidence of serious cases, but would also contribute to the general reduction of infections. This is then the main invitation to the public: to go to the vaccination points, as soon as possible, and receive their booster doses to confront this variant, if 4 months have already passed," said Fernández.
Additionally, he remarked that the evolution of Omicron in the country is asynchronous and, for now, has not appeared in some regions of the country. "Therefore, there is still some time to achieve early booster coverage and thus reduce the impact of the variant on the health system and its greater effects on public health, as its spread continues to rise," he remarked.
The available evidence on the different vaccines has shown that the booster dose increases neutralizing antibodies, which augments infection response, but much more importantly, prevents severe forms. Consequently, the booster protects the individual directly, especially for people at higher risk, but also indirectly by contributing to the reduction of collective infections.
In addition, taking into consideration the changes in the guideline for treating people who had close contact with confirmed cases, but remain asymptomatic and have a complete vaccination schedule, "the increase in booster coverage would make it even safer to exempt them from isolation since their probability of infecting others is lower, because now everyone who has completed their schedule after more than 4 months can be vaccinated," explained the director of Epidemiology.
In summary, the evidence suggests that given the current epidemiological situation with the emergence of the Omicron variant, "bringing the coverage of the booster dose forward in the population aged 18 and over by four months would increase the benefits for the population in the current epidemiological situation in the country," said Fernández, reiterating the call for the population to continue with self-care measures and to go to the vaccination points to start or complete their schedule and receive the booster.
