A Large Proportion of the Mexican Population Remained Susceptible to A(H1N1)pdm09 Infection One Year after the Emergence of 2009 Influenza Pandemic

Mexico: Lessons learned from the 2009 pandemic that help us fight COVID-19

In April 2009, Mexican, American, and Canadian authorities announced a novel influenza that became the first pandemic of the century. We report on lessons learned in Mexico. The Mexican Pandemic Influenza Preparedness and Response Plan, developed and implemented since 2005, was a decisive element for the early response. Major lessons-learned were the need for flexible plans that consider different scenarios; the need to continuously strengthen routine surveillance programs and laboratory capacity and strengthen coordination between epidemiological departments, clinicians, and laboratories; maintain strategic stockpiles; establish a fund for public health emergencies; and collaboration among neighboring countries. Mexico responded with immediate reporting and transparency, implemented aggressive control measures and generous sharing of data and samples. Lessons learned induced changes leading to a better response to public health critical events.

Clinical and laboratory findings of patients with the possible diagnosis of influenza hospitalized in affiliated hospitals of Babol University of Medical Sciences, 2015-2016

The clinical and para clinical manifestations of influenza in various patients have range from an autoimmune disease to a life-threatening respiratory infection. In addition, the severity of the disease is influenced by factors such as demographic factors, underlying diseases, and immune response. Therefore, in this study, we evaluated the clinical, laboratory and epidemiological characteristics of patients with this type of influenza in Babol (north of Iran). This study was conducted as a descriptive cross-sectional study from October 2015 to March 2016. Subsequently, in this study, records of 123 patients with clinical signs of the influenza-like disease who have undergone the clinical sign in hospitals affiliated to Babol University of Medical Sciences were reviewed. Of 123 patients admitted to a possible diagnosis of influenza, 58 patients (47.2%) were PCR positive for H1N1, while seventy nine (64.2%) participants were women and 21 (17.1%) had diabetes or underlying lung disease. Most of the involved age groups were of individuals above the age of 50. These were followed by the 21-35 years-old. Fever (78%), cough (65.9%), shivering (58.5%) and myalgia (56.1%) were the most common clinical symptoms. Increased levels of transaminases (43.1%), leukocytosis (35.8%) and thrombocytopenia (34.2%) were as well reported in patients as the most frequently reported para clinical findings. In the present study, the most usual clinical symptoms were fever, cough, chill, and myalgia, while gastrointestinal symptoms were also noticeably observed in patients. In an experimental study, a significant number of patients showed leukocytosis and thrombocytopenia and increased transaminases.

MF59-adjuvanted influenza vaccine (FLUAD®) elicits higher immune responses than a non-adjuvanted influenza vaccine (Fluzone®): A randomized, multicenter, Phase III pediatric trial in Mexico

The poor immune response elicited by trivalent influenza vaccines (TIVs) in children can be enhanced by the addition of adjuvants. This observer-blind, randomized Phase III trial assessed the immunogenicity and safety of the MF59-adjuvanted trivalent influenza vaccine FLUAD® (aTIV) and a non-adjuvanted TIV, in healthy children (aged 6 to <72 months) from 3 centers in Mexico, during the 2014-2015 season. The primary objectives were to assess the non-inferiority of aTIV to TIV, measured by geometric mean titers (GMTs), and the safety of aTIV and TIV. Seroconversion was one of several secondary objectives. In total, 287 children were enrolled. The non-inferiority criteria for GMTs and seroconversion were met for aTIV for all 3 vaccine strains. Lower bounds of the 95% confidence intervals for all 3 aTIV:TIV vaccine ratios were >2, showing that the immunogenicity of aTIV was superior to that of TIV for all 3 strains. Solicited adverse events (AEs) were experienced more frequently with aTIV than TIV by younger children (aged 6 to <36 months), but were more frequent with TIV than aTIV in older children (aged 36 to <72 months) who had been vaccinated previously. More unsolicited AEs were associated with aTIV than the TIV. All AEs were of mild or moderate severity. No deaths, serious AEs, or AEs leading to premature withdrawal were reported. Overall, aTIV was highly immunogenic and was well tolerated in healthy children 6 to <72 months of age. These results indicate that aTIV may be a beneficial addition to national pediatric vaccination programs.