Factors associated to the presence of headache in patients with influenza infection and its consequences: a 2010-2020 surveillance-based study.

Headache is a common symptom of influenza infection; however, its causes and consequences remain uncertain. In this manuscript, we analyzed which demographic and clinical factors were associated with the presence of headache during the course of influenza infection and whether patients with headache had a different prognosis, evaluated by need of hospitalization, sick leave or school absenteeism. The influence study (NCT05704335) was an observational study that analyzed data routinely collected from the Health Sentinel Network between 2010 and 2020. During the study period, 7832 cases were considered, among which, 5275 (67.4%) reported headache. The presence of headache was independently associated with myalgia (2.753; 95%CI: 2.456-3.087, P < 0.001), asthenia (OR: 1.958; 95%CI: 1.732-2.214, P < 0.001), shivering (OR: 1.925; 95%CI: 1.718-2.156, P < 0.001), nasopharyngeal erythema (OR: 1.505; 95%CI: 1.293-1.753, P < 0.001), fever (OR: 1.469; 95%CI: 1.159-1.861; P = 0.001), sudden onset of symptoms (OR: 1.380; 95%CI: 1.120-1.702, p = 0.004), female sex (OR: 1.134; 95%CI: 1.023-1.257, P = 0.018), and gastrointestinal symptoms (OR: 1.169; 95%CI: 1.039-1.315; P = 0.01). Patients with headache had a sex and age adjusted lower odds of being referred to the hospital (OR: 0.463; 95%CI: 0.264-0.812, P = 0.007) and a higher odd of having a sick leave and/or school absenteeism (absenteeism (OR: 1.342; 95%CI: 1.190-1.514, P < 0.001). In conclusion, the presence of headache seems associated with symptoms caused by the innate immune response. These findings support a headache pathophysiology linked with the innate immune response. Due to the potential negative consequences and its treatable nature, clinicians should systematically evaluate it and, whenever necessary, treat it too.

RSV Risk Profile in Hospitalized Adults and Comparison with Influenza and COVID-19 Controls in Valladolid, Spain, 2010-2022.

INTRODUCTION: We aimed to describe the risk profile of respiratory syncytial virus (RSV) infections among adults ≥ 60 years in Valladolid from January 2010 to August 2022, and to compare them with influenza and COVID-19 controls. METHODS: This was a retrospective cohort study of all laboratory-confirmed RSV infections identified in centralized microbiology database during a 12-year period. We analyzed risk factors for RSV hospitalization and severity (length of stay, intensive care unit admission, in-hospital death or readmission < 30 days) and compared severity between RSV patients vs. influenza and COVID-19 controls using multivariable logistic regression models. RESULTS: We included 706 RSV patients (635 inpatients and 71 outpatients), and 598 influenza and 60 COVID-19 hospitalized controls with comparable sociodemographic profile. Among RSV patients, 96 (15%) had a subtype identified: 56% A, 42% B, and 2% A + B. Eighty-one percent of RSV patients had cardiovascular conditions, 65% endocrine/metabolic, 46% chronic lung, and 43% immunocompromising conditions. Thirty-six percent were coinfected (vs. 21% influenza and 20% COVID-19; p = < .0001 and 0.01). Ninety-two percent had signs of lower respiratory infection (vs. 85% influenza and 72% COVID-19, p = < .0001) and 27% cardiovascular signs (vs. 20% influenza and 8% COVID-19, p = 0.0031 and 0.0009). Laboratory parameters of anemia, inflammation, and hypoxemia were highest in RSV. Among RSV, being a previous smoker (adjusted OR 2.81 [95% CI 1.01, 7.82]), coinfection (4.34 [2.02, 9.34]), and having cardiovascular (3.79 [2.17, 6.62]), neurologic (2.20 [1.09, 4.46]), or chronic lung (1.93 [1.11, 3.38]) diseases were risks for hospitalization. Being resident in care institutions (1.68 [1.09, 2.61]) or having a coinfection (1.91[1.36, 2.69]) were risks for higher severity, while RSV subtype was not associated with severity. Whereas RSV and influenza patients did not show differences in severity, RSV patients had 68% (38-84%) lower odds of experiencing any severe outcome compared to COVID-19. CONCLUSIONS: RSV especially affects those with comorbidities, coinfections, and living in care institutions. RSV vaccination could have an important public health impact in this population.

Respiratory Syncytial Virus Risk Profile in Hospitalized Infants and Comparison with Influenza and COVID-19 Controls in Valladolid, Spain, 2010-2022.

INTRODUCTION: We aimed to describe the risk profile of RSV infections among children aged ≤ 24 months in Valladolid from January 2010 to August 2022 and to compare them with influenza and COVID-19 controls. METHODS: We conducted a retrospective cohort study of all laboratory-confirmed RSV, influenza, and COVID-19 infections. We analyzed risk factors for RSV hospitalization and severity (length-of-stay ≥ 8 days, intensive-care-unit admission, in-hospital death or readmission < 30 days) and compared severity between hospitalized RSV patients vs. influenza and COVID-19 controls using multivariable logistic regression models. RESULTS: We included 1507 patients with RSV (1274 inpatient), 32 with influenza, and 52 COVID-19 controls. Hospitalized RSV (mean age 5.3 months) and COVID-19 (4 months) were younger than influenza (9.1 months) patients. Sixteen percent of patients had RSV within the first month of life. Most infants did not have comorbidities (74% RSV, 56% influenza, and 69% COVID-19). Forty-one percent of patients with RSV and influenza were coinfected vs. 27% COVID-19 (p = 0.04). Among RSV, hospitalization risk factors were prematurity (adjusted OR 3.11 [95% CI 1.66, 4.44]) and coinfection (2.03 [1.45, 2.85]). Risks for higher severity were maternal smoking (1.89 [1.07, 3.33]), prematurity (2.31 [1.59, 3.34]), chronic lung disease (2.20 [1.06, 4.58]), neurodevelopmental condition (4.28 [2.10, 8.73]), and coinfection (2.67 [2.09, 3.40]). Breastfeeding was protective against hospitalization (0.87 [0.80, 0.95]) and severity (0.81 [0.74, 0.88]), while complete vaccination schedule was protective against severity (0.51 [0.27, 0.97]). RSV had 2.47 (1.03, 5.96) higher risk of experiencing any severe outcome compared to influenza and did not show significant differences vs. COVID-19. CONCLUSIONS: RSV hospitalizations were more frequent and severe than influenza, while severity was comparable to the early pandemic COVID-19. Currently, both influenza and COVID-19 vaccines are included in the maternal and childhood Spanish immunization schedule between the ages of 6 and 59 months. RSV monoclonal antibody is recommended for ≤ 6 months but a third of patients were aged 6-24 months. Maternal RSV vaccination can protect their children directly from birth and indirectly through breastfeeding.