[Parotitis and influenza: unusual association during 2017, in Santa Fe, Argentina]. / Parotiditis e influenza: inusual asociación durante 2017, en Santa Fe, Argentina.

BACKGROUND: Parotitis is an acute viral disease characterized by swelling and pain in one or both salivary glands, submaxillary or submental, fever, headache, muscle ache and/or fatigue. AIM: To investigate the occurrence of influenza virus infection in parotitis cases in a population of Santa Fe during 2017 and analyze clinical and epidemiological characteristics of the cases. METHODS: We studied patients with diagnosis of mumps without age restriction, who came for examination from week 26 to the network of clinicians forming the Sentinel Influenza Unit in Santa Fe. RESULTS: Between epidemiological weeks 26 and 44, 22 clinical parotitis cases we enrolled. The influenza virus was detected in 68.2%, influenza A (H3N2) 93%, and influenza B, 7%. The clinical signs of cases were mild, with an average swelling development of 5 days and no complications. 74% presented with influenza-like illness in tandem with parotitis. CONCLUSIONS: This study provides evidence that a proportion of children presenting with parotitis had influenza A(H3N2) virus infection. It is necessary to implement systematic surveillance of parotitis associated with influenza and differential diagnosis even in the absence of respiratory symptoms.

The epidemiological signature of influenza B virus and its B/Victoria and B/Yamagata lineages in the 21st century.

We describe the epidemiological characteristics, pattern of circulation, and geographical distribution of influenza B viruses and its lineages using data from the Global Influenza B Study. We included over 1.8 million influenza cases occurred in thirty-one countries during 2000-2018. We calculated the proportion of cases caused by influenza B and its lineages; determined the timing of influenza A and B epidemics; compared the age distribution of B/Victoria and B/Yamagata cases; and evaluated the frequency of lineage-level mismatch for the trivalent vaccine. The median proportion of influenza cases caused by influenza B virus was 23.4%, with a tendency (borderline statistical significance, p = 0.060) to be higher in tropical vs. temperate countries. Influenza B was the dominant virus type in about one every seven seasons. In temperate countries, influenza B epidemics occurred on average three weeks later than influenza A epidemics; no consistent pattern emerged in the tropics. The two B lineages caused a comparable proportion of influenza B cases globally, however the B/Yamagata was more frequent in temperate countries, and the B/Victoria in the tropics (p = 0.048). B/Yamagata patients were significantly older than B/Victoria patients in almost all countries. A lineage-level vaccine mismatch was observed in over 40% of seasons in temperate countries and in 30% of seasons in the tropics. The type B virus caused a substantial proportion of influenza infections globally in the 21st century, and its two virus lineages differed in terms of age and geographical distribution of patients. These findings will help inform health policy decisions aiming to reduce disease burden associated with seasonal influenza.

Parotiditis e influenza: inusual asociación durante 2017, en Santa Fe, Argentina / Parotitis and influenza: unusual association during 2017, in Santa Fe, Argentina

Resumen Introducción: La parotiditis es una enfermedad vírica aguda caracterizada por tumefacción y dolor en una o ambas glándulas salivales, submaxilar o submentoniana, fiebre, dolor de cabeza, dolor muscular y/o fatiga. Objetivos Investigar la ocurrencia de infección por el virus influenza en casos de parotiditis en una población de Santa Fe, durante 2017 y analizar las características clínicas y epidemiológicas de los casos. Materiales y Métodos: Se estudiaron pacientes con diagnóstico de parotiditis, que acudieron a la consulta desde la semana 26 en la red de médicos que forman la Unidad Centinela de Influenza en Santa Fe. Resultados: Entre las semanas epidemiológicas 26 y 44, se incluyeron 22 casos de parotiditis clínica. El virus influenza se detectó en 68,2%, influenza A (H3N2) 93% e influenza B 7%. Los síntomas clínicos de los casos fueron leves, con una tumefacción de cinco días y sin complicaciones. El 74% presentó una enfermedad tipo influenza en conjunto con la parotiditis. Conclusiones: Este estudio evidencia que niños que presentaban parotiditis tenían una infección por el virus de la influenza A (H3N2). Es necesario implementar una vigilancia sistemática de las parotiditis asociadas con influenza y el diagnóstico diferencial, incluso en ausencia de síntomas respiratorios.

Background: Parotitis is an acute viral disease characterized by swelling and pain in one or both salivary glands, submaxillary or submental, fever, headache, muscle ache and/or fatigue. Aim: To investigate the occurrence of influenza virus infection in parotitis cases in a population of Santa Fe during 2017 and analyze clinical and epidemiological characteristics of the cases. Methods: We studied patients with diagnosis of mumps without age restriction, who came for examination from week 26 to the network of clinicians forming the Sentinel Influenza Unit in Santa Fe. Results: Between epidemiological weeks 26 and 44, 22 clinical parotitis cases we enrolled. The influenza virus was detected in 68.2%, influenza A (H3N2) 93%, and influenza B, 7%. The clinical signs of cases were mild, with an average swelling development of 5 days and no complications. 74% presented with influenza-like illness in tandem with parotitis. Conclusions: This study provides evidence that a proportion of children presenting with parotitis had influenza A(H3N2) virus infection. It is necessary to implement systematic surveillance of parotitis associated with influenza and differential diagnosis even in the absence of respiratory symptoms.