Expired Chickenpox Vaccine Doses Administered to Boys in Argentina Kindergarten

Boys between three and five years old from a kindergarten in the Buenos Aires municipality of Moreno received this week doses of the chickenpox vaccine that had expired eight months ago. It was during the school campaign to update pediatric vaccination, which is still delayed in the country after the covid-19 pandemic. As La Nación learned, another district to the west of the province of Buenos Aires had 153 doses of the same batch.

The Merck laboratory, producer of the Varivax live virus vaccine against chickenpox, confirmed to this medium that the batch No T031427 to which the doses applied last Tuesday belong to Jardín 908 “Tambor de Tacuarí”, in the San José neighborhood, it had been drawn up on September 15, 2020 and expired on September 15 of last year. Its shelf life had also not been extended, as was the case with Covid vaccines during the pandemic.

They should have been discarded with the procedures that are foreseen for the handling of biological products.

By the date of preparation, lot T031427 would correspond to the annual supply of calendar vaccines that the country regularly acquires through a special fund of the Pan American Health Organization (PAHO) for access to this input in the region. Doses must be delivered to countries with no less than 12 months before expiration. Once received, the Ministry of Health of the Nation distributes them to the provinces and, these, within their territories. The Ministry of Health of Moreno specified to this medium that the doses applied last Tuesday had been received in May of last year.

The application of these doses occurs when calendar vaccination coverage in the country lags behind.

The Argentine Society of Pediatrics recently estimated that more than a million children and adolescents in the country would be left each year without up-to-date recommended vaccines, as published by La Nación. Consulted infectologists expressed concern about the lack of controls and the risk of vaccinating with calendar doses without guaranteeing the expected protection. That a vaccine is expired means that the producer does not guarantee its immunogenicity and its application, as members of the immunization programs in the provinces usually explain, is considered an “invalid dose.”

Worry

In the Moreno kindergarten, it was the mothers of the children between the ages of three and five who noticed this irregularity in the municipal operation coordinated by the La Perlita Primary Care Center. In the vaccination books, the label of the applied dose appears with the expiration date that the health personnel, the director of the local health unit or the garden authorities did not notice, according to what the mothers reported in dialogue with two local media – Weekly News and Unwire-.

(IN)