MercoPress. South Atlantic News Agency

Argentina to start applying 5th dose of COVID-19 vax

The XBB subvariant is expanding rapidly in a world where sanitary measures have been relaxed

Argentina's Federal Health Council (COFESA) has agreed to move on with the fifth dose, or third booster of a Covid-19 vaccine por patients who received the second dose over 120 before.

The Health Ministers of all 24 districts (23 provinces plus the Autonomous City of Buenos Aires) plus that of the federal government also assured that the country has the necessary vaccines to start this new stage, which will prioritize people over 50 years of age and those with comorbidities.

This decision was reached after the experts studied the epidemiological situation and the experiences of other countries in the application of boosters, the time elapsed since the second booster, i.e. six months, and the benefits demonstrated by the Covid-19 vaccines to avoid complications, hospitalizations, and deaths.

The experts also insisted on the need to visit vaccination centers in order to maintain this positive epidemiological context and urged people who have not yet taken any booster dose to do so as soon as possible.

Regarding the virus, the experts said “it has not shown a defined seasonality like other diseases, with an increase in cases even during the summer; therefore, it is important to continue offering the possibility of being more protected, especially to the most at-risk populations.”

Nearly 110 million doses have been applied nationwide. Over 41 million Argentines received the first dose and more than 37.5 million have taken the initial scheme, with over 3 million having taken an additional dose. Almost 22 million are vaccinated with the first booster and a little more than six million received the second booster, it was reported.

Meanwhile, a study released last week showed that although cases are “very rare,” patients who have taken the first shot of the Astra Zeneca vaccine are 30% more likely to suffer a case of thrombosis (thrombocytopenia) than those who were injected with Pfizer/BioNTech's. Thrombocytopenia is the formation of a blood clot with potentially fatal consequences.

Following the launch of coronavirus vaccination campaigns from 2021, a link was quickly suspected between vial-vector vaccines - AstraZeneca and Johnson & Johnson - and the occurrence of these blood disorders. The study, conducted on the basis of health data from millions of patients in several countries in Europe and the United States, confirms that these thromboses are more frequent after the AstraZeneca vaccine, although they are very rare: 862 cases per more than one million vaccinees. After the second dose, there is no difference between the AstraZeneca and Pfizer/BioNTech vaccines, it was reported. As for the one-dose Johnson & Johnson vaccine, the data point to an increased risk, but not in a clear enough way for the researchers to conclude, according to the study.

While vaccination continues, a new variant of SARS-CoV-2 known as XBB has emerged in Asia and is spreading fast and can evade the immune system. A subvariant of the Omicron strain, which wreaked havoc worldwide between late 2021 and early 2022, causing record numbers of cases in dozens of countries, XBB is causing waves of infections and hospitalizations, particularly in Singapore and India.

The XBB subvariant of the Omicron strain of SARS-CoV-2 was discovered in August this year in the Indian city of Kolkata, the capital of the state of West Bengal. Since then, it has spread to 26 countries and is causing new waves of contagions in Bangladesh and Singapore. XBB combines two subvariants of Omicron BA.2. In this case, XBB stems from the mixture of Omicron BA.2.10.1 and Omicron BA.2.75. The great concern about this virus lies in its ability to evade the immune system, overcoming antibodies generated both naturally and through vaccination, which could spark a new wave of infections worldwide, as sanitary measures have been relaxed.