Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mimics the influenza A (H1N1) virus in terms of clinical presentation, transmission mechanism, and seasonal coincidence. Comprehensive data for the clinical severity of adult patients co-infected by both H1N1 and SARS-CoV-2, and, particularly, the relationship with PCR cycle threshold (Ct) values are not yet available. All participants in this study were tested for H1N1 and SARS-CoV-2 simultaneously at admission. Demographic, clinical, treatment, and laboratory data were extracted from electronic medical records and compared among adults hospitalized for H1N1 infection, SARS-CoV-2 infection and co-infection with both viruses. Ct values for viral RNA detection were further compared within SARS-CoV-2 and co-infection groups. Score on seven-category ordinal scale of clinical status at day 7 and day 14 were assessed. Among patients with monoinfection, H1N1 infection had higher frequency of onset symptoms but lower incidence of adverse events during hospitalization than SAR-CoV-2 infection (P < 0.05). Co-infection had an increased odds of acute kidney injury, acute heart failure, secondary bacterial infections, multilobar infiltrates and admittance to ICU than monoinfection. Score on seven-category scale at day 7 and day 14 was higher in patients with coinfection than patients with SAR-CoV-2 monoinfection (P<0.05). Co-infected patients had lower initial Ct values (referring to higher viral load) (median 32) than patients with SAR-CoV-2 monoinfection (median 36). Among co-infected patients, low Ct values were significantly and positively correlated with acute kidney injury and ARDS (P = 0.03 and 0.02, respectively). Co-infection by SARS-CoV-2 and H1N1 caused more severe disease than monoinfection by either virus in adult inpatients. Early Ct value could provide clues for the later trajectory of the co-infection. Multiplex molecular diagnostics for both viruses and early assessment of SAR-CoV-2 Ct values are recommended to achieve optimal treatment for improved clinical outcome. Author summary The baseline enrolled 505 patients admitted to Guangzhou Eighth People’s Hospital (Guangzhou, Guangdong) with a diagnosis of COVID-19 or H1N1. All the patients were tested by both viruses at admission. Demographic, clinical, treatment, and laboratory data were extracted from electronic medical records and compared among adults (≥18 years) hospitalized for H1N1 infection ( n = 220), SARS-CoV-2 infection ( n = 249) and co-infection with both viruses ( n = 36). The prevalence rate of H1N1 co-infection was 12.6% (36/285) among patients hospitalized with COVID-19. Co-infection affected a predominantly older age group and was associated with poorer clinical outcome. We also described the viral load trajectory in patients with diverse types of infection. Lower initial Ct values (higher viral loads in nasopharyngeal swabs) of co-infected patients was found to be associated with a higher number of adverse events and clinical symptoms. Considering the COVID-19 pandemic and a simultaneous epidemic of seasonal influenza, the data in China may critically inform future therapeutic or prophylactic strategies, especially for other developing countries.
【초록키워드】 Treatment, severe acute respiratory syndrome coronavirus 2, viruses, SARS-CoV-2, ARDS, coronavirus, Hospitalized, SAR-CoV-2, Clinical symptoms, Hospitalization, Influenza, SARS-COV-2 infection, COVID-19 pandemic, Infection, Transmission, Acute kidney injury, Symptom, Prophylactic, severe acute respiratory syndrome Coronavirus, virus, influenza A, diagnostics, ICU, clinical status, Clinical outcome, adverse events, Prevalence, China, heart failure, Acute heart failure, Coinfection, Epidemic, Viral, Viral load, nasopharyngeal swabs, adverse event, Patient, Older age, Co-infection, Ct value, trajectory, H1N1, Viral RNA, Secondary bacterial infections, incidence, molecular, respiratory, electronic medical records, threshold, demographic, Bacterial infections, Admission, patients, mechanism, score, Clinical severity, Ordinal Scale, Frequency, severe disease, Ct values, Guangzhou, medical records, prevalence rate, Inpatients, Seasonal influenza, acute respiratory syndrome, acute respiratory syndrome coronavirus, All participants, Adult patients, laboratory data, both viruses, seven-category ordinal scale, all the patients, admittance, Lower, Guangdong, H1N1 infection, viral RNA detection, electronic medical record, initial, Comprehensive, PCR cycle, enrolled, tested, described, affected, caused, significantly, median, groups, both virus, adults hospitalized, All participant, All the patient, baseline, diagnosis of COVID-19, future therapeutic, patients hospitalized, positively correlated, were assessed, with COVID-19, 【제목키워드】 SARS-CoV-2, Infection, clinical, Inpatient, Virological,