“Expired Chickenpox Vaccines Given to Argentine Kindergarten Boys: Concerns Over Immunogenicity and Invalid Doses”

Boys between three and five years old from a kindergarten in the Buenos Aires municipality of Moreno received eight-month-old doses of the chickenpox vaccine this week. It was during the school campaign to update pediatric vaccination, which is still behind schedule in the country after the coronavirus pandemic. Covid-19. as he could know THE NATIONanother district to the west of the province of Buenos Aires had 153 doses of the same lot.

The laboratory Merckproducer of the live virus vaccine against chickenpox Varivaxconfirmed to this medium that the lot No T031427 to which belong the doses applied last Tuesday in the Garden 908 “Tacuari Drum”, in the San José neighborhood, 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 had to be discarded with the procedures provided for the handling of biological products.

Due to the date of preparation, batch T031427 would correspond to the annual supply of calendar vaccines that the country regularly acquires through a special fund from 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 THE NATION. 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 “invalid dose”.

In the Moreno kindergarten, it was the mothers of the boys 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 booklets, the label of the applied dose appears with the expiration date that the health person, 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–.

The women told that last Tuesday a talk about dengue and the control of the vaccination booklet had been organized. One of them, when she saw the notebook at the door, went in to ask if the date of the applied dose was of preparation or expiration.

“We did not know that the director of the ward was there, a nurse and two health promoters,” said the woman. When they look at the jars, they realize that everything was expired.. Passing the photo of my daughter’s notebook [por WhatsApp]other moms start checking and discover that last year’s doses against chickenpox were also expired. At the meeting we had yesterday [por el jueves] with people from the municipal Health Secretariat and the Moreno Hospital, they tried to bring us peace of mind and there they realized that they applied doses to three-year-olds that were not appropriate.”

The scheme for chickenpox includes the first dose at 15 months of age and the second at school entry. In the Moreno kindergarten, as the families denounced, boys from the 3 and 4-year-old rooms were also vaccinated with doses from that batch.

“By mistake, expired doses were given,” they responded to the THE NATION from the mayor of Moreno Party in charge of Mariel Fernandez (Front of All). “Families were summoned and apologized. The two responsible for the operation were removed and are available until the summary is resolved. Families were informed that the application had no adverse effects and that these doses will be applied again in a month,” they indicated.

Ana Cabana, Secretary of Health of Moreno, said that this Tuesday afternoon two three-year-old boys, one four-year-old, two five-year-olds and two other boys received an expired dose for chickenpox, whose age was not specified and were vaccinated that day. But, still, the families did not respond to the secretariat team that tried to contact them. “There are six reported cases of adverse events supposedly attributable to vaccination and immunization (Esavi) on our behalf,” the official explained. All Esavi is mandatory notification to the provincial and national Health ministries.

“On Wednesday the fridge was closed [con el stock de vacunas] in the center that was in charge of the vaccination operation and it was reviewed – Cabaña continued -. The refrigerator is cleaned monthly. and the vial that has not been used by the expiration date is discarded as yellow waste for destruction.” This process, as he explained, is in charge of a pathological waste management company hired by the municipality.

For Silvia Gonzalez Ayalapresident of the Argentine Society of Pediatric Infectious Diseases (Sadip), “it is very serious that expired vaccines have been applied: that is called programmatic error. They are live attenuated virus vaccines, so it would be necessary to assume that they lost potency”. Due to their ages, he considered that the youngest had not been vaccinated during the pandemic and those five years old needed the second dose.

“This is related to the fall in vaccination: vaccines remained unapplied and the stock was not monitored. The boys received an injection that most likely would not be useful to them or would be of very little use,” said the specialist, who is a professor at the Department of Infections in Perinatology at the Faculty of Health Sciences at the Catholic University of La Plata. .

“They are vaccines that should not have been applied,” he said. edward lopezhead of the Department of Medicine of the Children’s Hospital Ricardo Gutierrez. “The boys who received them were not adequately protected and we do not know how many doses were applied. The problem here is the false sense of protection: A dose of the varicella vaccine provides very high protection in the early years, with a failure of between 5 and 10%, according to published studies”, added the infectologist.