Aims and objectives
Influenza A H1N1 virus is the subtype of influenza virus that typically leads to a moresevere infection than the usual seasonal influenza virus.
It was the cause of the last influenzaglobal outbreak in 2009,
which resulted in thousands of deaths worldwide,
principally amongyoung individuals and pregnant woman.
Since then,
the H1N1 influenza virus has assumed aseasonal spreading similar to other influenza types and continues to cause substantial morbidity,although it is controlled with the immunization programs.[1] Nevertheless,
an atypical outbreakoccurred in South America in 2016,
which...
Methods and materials
The institutional review board approved this retrospective study and waived therequirement for informed consent.
The database from our institution was searched forconsecutive patients with a diagnosis of influenza A H1N1 in 2016 as assessed via the upperairway by nasopharyngeal swabbing or a washing test with polymerase chain reaction.
Theinclusion criteria were a positive test for influenza A H1N1 and chest radiograph (CR) and/orchest computed tomography (CT) within 48hours before or after the positive test.
The exclusioncriteria were another confirmed concomitant pulmonary infection and the absence...
Results
Our study population (Figure 3.) consisted of 160 patients,
including 80/160(50%) men and 80/160(50%) women,
with a median age of 43 years(IQR:32-56).
49/160(30.6%) patients had comorbidities,
12/160(7.5%) had DM,29/160 (18.1%) had systemic hypertension,
4/160(2.5%) had COPD,
6/160(3.8%) had another pneumopathy and 8/160(5.0%) had immunosuppression.Five of 160(3.1%) patients were smokers.
None of the patients had asthma.
The vast majority ofthe included patients (147/160,91.8%) were diagnosed in March and April.
Concerning the clinical manifestations at admission,
144 patients had this informationwritten in the medical records.
Based on...
Conclusion
Our study population was obtained from our database throughout the year of 2016;however,
all patients selected had the H1N1 infection diagnosed between the three monthsbefore winter in the south hemisphere,
which configured an atypical and early outbreak of H1N1infection.[11]
The major clinical findings among our population were flu-like symptoms (97.9%) asexpected for a respiratory infection.[12] DM,
systemic hypertension,
dyspnea,
thoracic pain,temperature and CRP levels were the clinical features associated with worse clinical outcomes.Moreover,
the radiological findings were the presence of pulmonary infiltrate,
consolidation,
andpleural effusion...
References
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