Vaccine Johnson & Johnson, WHO: “Yes depending on the dose at 2 or 6 months even heterologous”

Janssen’s single-dose Covid vaccine (Johnson & Johnson group) is effective and countries may consider using one or two courses of immunization depending on the circumstances, thus evaluating the advisability of a booster, including a heterologous one ( with mRna products) at 2 or 6 months depending on the epidemiological situation and the needs of the different subgroups of the population. These, in summary, are the interim recommendations of the World Health Organization on the J&J vaccine, drawn up on the basis of suggestions to the Agency’s Strategic Advisory Group of Experts (Sage) on Immunization and available evidence. “In some circumstances – explains WHO – the use of a single dose” still today “can have advantages”, considering that “many countries face serious limitations in the supply of vaccines, associated with a high burden of disease In fact, a single dose of the “J&J” vaccine is effective – experts assure – and allows for a rapid increase in vaccination coverage, which in turn will reduce the impact of “Covid-19″ on health systems, preventing serious outcomes of the disease. single dose may also be a preferred option for vaccinating hard-to-reach populations or those living in conflict-affected or insecure settings. ” That said, “a second dose may be appropriate as vaccine stocks and / or accessibility increase.” In particular, “countries should consider offering” J&J vaccinates “a second dose. – WHO specifies – starting with the highest priority groups (for example health workers, the elderly and people with comorbidities). The administration of the booster will result in greater protection against symptomatic infection and serious illness. For the second dose can also be considered a heterologous vaccine “and the interval can also be decided based on the circumstances:” A booster 2 months after the initial dose substantially increases efficacy, especially against symptomatic infections, even when caused by variants of concern of Sars-CoV-2 “, confirm the experts. But “it has been shown that an even longer interval between the two doses (6 months instead of 2) results in a greater increase in immune responses in adults. Countries could therefore consider an interval of up to 6 months, depending on their situation. epidemiological and the needs of the various subpopulations “.