Mendoza: Early Flu Campaign 2026 Begins with 30,000 Doses & H3N2 Variant Focus

The annual influenza campaign in Argentina is underway earlier than usual this year, prompted by the circulation of a new H3N2 subclade K variant. In Mendoza province, the rollout began this week with the arrival of an initial shipment of 30,000 doses, according to provincial immunization chief Iris Aguilar. This proactive measure reflects a nationwide effort to bolster public health defenses against a potentially challenging flu season.

The decision to accelerate the vaccination program was made at the national level, responding to the increased transmissibility of the H3N2 subclade K strain, which has already demonstrated a significant presence in the Northern Hemisphere. Argentina’s Ministry of Health has procured a total of 8.16 million doses for the 2026 campaign, encompassing formulations for adults, seniors, and pediatric populations. This early start aims to ensure that vulnerable groups are protected before the peak of winter arrives, minimizing the potential for severe illness, hospitalizations, and fatalities associated with influenza.

Mendoza Receives Initial Vaccine Shipment

Iris Aguilar confirmed the arrival of the first 30,000 doses on Monday, February 23rd, stating, “Las vacunas se recibieron este lunes 23 de febrero. Estamos distribuyendo alrededor de 30.000 dosis” (The vaccines were received this Monday, February 23rd. We are distributing around 30,000 doses), as reported by El Sol. The province is prioritizing distribution to healthcare workers and other at-risk groups. The formal launch of the campaign across Mendoza is scheduled for March 2nd, a week ahead of other jurisdictions in the country.

Outdated Stock from 2025 Will Not Be Used

A key point of discussion surrounding the campaign is the handling of leftover vaccine doses from 2025. Aguilar was clear that these doses will not be utilized. “Cambia la cepa todos los años y si quedaba alguna se vencieron en enero” (The strain changes every year and if any remained, they expired in January), she explained. This underscores the importance of annual vaccine updates to match circulating viral strains. The 2026 vaccine is specifically formulated to provide protection against the H3N2 subclade K variant, rendering previous formulations ineffective. The annual update is crucial as influenza viruses constantly evolve, necessitating new vaccine compositions to maintain optimal protection.

Who is Eligible for the 2026 Flu Vaccine in Mendoza?

The Mendoza provincial government, through the Ministry of Health and Sports, has identified specific priority groups for vaccination. These include:

• Healthcare personnel
• Children aged 6 to 24 months
• Pregnant individuals, in any trimester
• Postpartum women, up to ten days after delivery
• Individuals over 65 years of age
• Individuals under 64 years of age with comorbidities (with a medical certificate)

Vaccines will be available at health centers, public hospitals, and the Central Vaccination Center throughout Mendoza province. This widespread accessibility aims to maximize vaccination coverage within the prioritized groups.

Increased Transmissibility of the H3N2 Subclade K Variant

The decision to expedite the vaccination campaign was made following a consensus reached at the Federal Health Council (COFESA). Officials cited the early onset of the respiratory virus season and the emergence of the highly transmissible H3N2 subclade K variant as key factors driving the accelerated timeline. Whereas the new variant is not currently associated with increased disease severity, its heightened transmissibility raises concerns about potential strain on the healthcare system. The Ministry of Health emphasized that proactive vaccination of at-risk groups is essential to reduce complications, hospitalizations, and deaths related to influenza.