#Management of #critical illness in an #adolescent caused by highly pathogenic avian #influenza #H5N1 virus infection in #BC, #Canada

 

Summary

Highly pathogenic avian influenza A(H5N1) viruses have been circulating among wild birds and are enzootic in poultry in some areas of the world with spillover to a wide range of terrestrial and marine mammals. Since 1997, sporadic animal to human, primarily poultry to human, transmission of highly pathogenic avian influenza A(H5N1) viruses has been reported in 25 countries. More recently there have been locally acquired infections in the Americas due to the 2.3.4.4b clade of the virus. Most of the recently detected human infections in the USA have been relatively mild but there have been cases of critical illness reported in several countries. In this Grand Round we present the first locally acquired highly pathogenic avian influenza A(H5N1) virus infection in Canada, which was in a 13-year-old female, who developed severe disease requiring prolonged critical care. She was infected with a clade 2.3.4.4b, genotype D1.1 virus and developed evidence of cytokine storm and received several modalities of care including combination antiviral therapy, renal replacement therapy, therapeutic plasma exchange, and invasive mechanical ventilation support with veno-venous extracorporeal life support. She recovered and was discharged home without requirement for additional support. This Grand Round describes important clinical and management considerations for critically ill patients infected with highly pathogenic avian influenza A(H5N1) virus.

Source: Lancet Infectious Diseases, https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00773-X/abstract?rss=yes

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#Clinical Features and #Management of a Critical #Human Case of #H10N3 Avian #Influenza: A Case Report and Literature Review

 

Highlights

• Nonspecific early signs hinder prompt diagnosis of H10N3 infection.

• H10N3 human infection remains rare but with high clinical severity.

• All patients had bird exposure and developed fever, cough, and dyspnoea.

• Diagnosis was confirmed by sequencing; imaging revealed viral pneumonia.

Abstract

Background

Since the first human case of H10N3 Avian Influenza in Jiangsu, China (April 2021), three cases have been reported globally. However, clinical and treatment data remain limited. Therefore, we describe the fourth patient’s epidemiology, clinical manifestations, diagnostics, treatment.

Case presentation

A 23-year-old woman, previously well, presented on 12 Dec 2024 with fever, dry cough and breathlessness after pig and chicken contact. CT showed bilateral pneumonia. Despite high-flow oxygen and broad-spectrum antibiotics she deteriorated, requiring intubation, lung-protective ventilation and VV-ECMO. Bronchoalveolar lavage isolated H10N3 influenza virus. Treatment with oseltamivir and baloxavir plus prone-position ventilation led to clinical improvement.

Conclusion

Due to its nonspecific early symptoms, H10N3 is difficult to diagnose promptly, increasing the risk. Early recognition, antiviral therapy, and aggressive support are essential in managing severe infections.

Source: 

Link: https://www.ijidonline.com/article/S1201-9712(26)00002-0/fulltext

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A case of #H10N3 avian #influenza in a young woman

 

Context and significance

The avian influenza A virus subtype H10N3 is a possible candidate for causing a fatal flu and may present a serious public health threat. Research increasingly shows that the avian influenza virus H10N3 can be transmitted from birds to humans, causing severe viral pneumonia and potentially leading to acute respiratory distress syndrome and respiratory failure. Researchers at the Fourth People’s Hospital of Nanning (China) provide evidence supporting the cross-species transmission of the avian influenza virus H10N3 to humans, which can give rise to severe pneumonia. The authors report that a female patient with avian influenza virus H10N3 infection, who was suffering from severe pneumonia, respiratory failure, pneumothorax, and numbness and dysesthesia in her feet, recovered after receiving appropriate therapy and was discharged from the hospital.

Highlights

• A young woman contracted the avian influenza virus H10N3

• Secondary infections, pneumothorax, and foot numbness developed consecutively

• Baloxavir marboxil and oseltamivir were administered

Summary

Background

Avian influenza viruses, frequently identified in wild waterfowl and poultry, have occasionally been transmitted to humans, causing severe respiratory diseases. This report covers the fourth case of a human contracting the H10N3 subtype of avian influenza virus.

Methods

A case of novel avian influenza virus subtype H10N3 was detected in a female patient hospitalized in Nanning, China, in December 2024. Blood, feces, urine, and bronchoalveolar lavage fluid were collected from the patient for medical analysis during the hospitalization.

Findings

A case of novel avian influenza virus subtype H10N3 was detected in a female patient hospitalized in Nanning, China, in December 2024. She also had a history of exposure to live poultry. This case represents the fourth documented instance of H10N3 infection in humans. She was treated with a combination of baloxavir marboxil and oseltamivir. She exhibited extensive lung lesions. Additionally, she presented complicating factors, including secondary infection, pneumothorax, and numbness in her feet. She recovered and was discharged on March 27, 2025, amid comprehensive supportive care, which included therapy with baloxavir marboxil, oseltamivir, fluconazole, tigecycline, amikacin, extracorporeal membrane oxygenation, and rehabilitation therapy.

Conclusions

The virus was effectively cleared by the combination therapies. The internal genes of the H10N3 virus in this patient were highly homologous to the corresponding genes from the A/Yunnan/2024 virus (GenBank accession numbers, hemagglutinin [HA] [GenBank: PP555669] and PB-2 [GenBank: PP555666]).

Funding

This work was funded by the Fourth People’s Hospital of Nanning - Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome (HIV/AIDS) Clinical Treatment Center of Guangxi (Nanning).

Source: Med., https://www.cell.com/med/abstract/S2666-6340(25)00272-7

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Higher #mortality in #ECMO patients during the #COVID19 #pandemic compared with #H1N1 #influenza: implications for future pandemics

 

Highlights

-- Higher Mortality in COVID-19 ECMO Patients: COVID-19 patients on ECMO had a significantly higher in-hospital mortality rate (52%) compared to H1N1 patients (6%) (p < 0.0001).

-- Increased Complications in COVID-19: COVID-19 patients had a higher incidence of complications, including:

• Secondary bloodstream infections (OR = 14.3; p = 0.003)

• Neurological complications

• Acute kidney injury requiring renal replacement therapy (RRT)

-- Longer ECMO Duration in COVID-19: COVID-19 patients required longer durations of ECMO support compared to H1N1 patients.

-- Age and Comorbidities Impact Mortality: Even after adjusting for age, BMI, gender, and ECMO duration, COVID-19 conferred a 16-fold higher risk of mortality compared to H1N1 (adjusted OR = 16.8).

Abstract

Background

Veno-venous Extracorporeal Membrane Oxygenation (V-V ECMO) in management of refractory respiratory failure due to viral respiratory infections has increased with recent pandemics.

Aims

The aim was to compare clinical characteristics and outcomes of patients requiring ECMO support during an evolving pandemic with COVID-19, with patients during the H1N1-influenza pandemic and subsequent seasonal epidemics, where adjunct therapy and vaccination was available.

Methods

Medical records of inpatients at an ECMO referral centre diagnosed with COVID-19 between March 2020 and October 2022 and requiring ECMO support were analysed. The clinical characteristics and outcomes of these patients were compared to data from patients with H1N1 influenza requiring ECMO between July 2009 and August 2017, treated at the same centre. The primary outcome of in-hospital mortality was analysed with a multivariate logistic regression model; categorical and continuous variables were compared using Fisher’s exact tests and two-sample T-tests, respectively.

Results

ECMO was used in 27 COVID-19 patients and 32 H1N1 influenza patients. Compared with H1N1 patients, COVID-19 patients were older (49.2±9.0 vs 42.3±11.1 years,p=0.01), and more likely to have comorbidities (59% vs 28%,p=0.02). Mortality was significantly higher for COVID-19 patients (52% vs 6%,p<0.0001), odds ratio 16.8 (95% CI: 1.27 - 221.39,p<0.05). Days on ECMO were longer in the COVID-19 group (20±13.3 vs 10±5.6 days,p<0.001). ECMO-related complication rates were similar between groups, apart from higher rates of secondary blood stream infections in COVID-19 patients (44% vs 6%,p<0.001).

Conclusion

Outcomes in patients with COVID-19 requiring ECMO support were worse than those requiring similar support during H1N1 seasons.

Source: Respiratory Medicine, https://www.resmedjournal.com/article/S0954-6111(25)00374-9/abstract

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In-hospital #outcomes and 6-month follow-up results of #patients supported with #ECMO for #COVID19 from the 2nd wave to end of pandemic (EuroECMO-COVID)...

Summary

Background

Extracorporeal membrane oxygenation (ECMO) for COVID-19 was thoroughly assessed during the first pandemic wave, but data on subsequent waves are limited. We aimed to investigate in-hospital and 6-month survival of patients with COVID-19 supported with ECMO from the second pandemic wave (Sept 15, 2020) until the end of the pandemic (March 21, 2023, announced by WHO).

Methods

EuroECMO-COVID is a prospective, observational study including adults (aged ≥16 years) requiring ECMO respiratory support for COVID-19 from 98 centres in 21 countries. We compared patient characteristics and outcomes between in-hospital survivors and non-survivors. Mixed-effects multivariable logistic regressions were used to investigate factors linked to in-hospital mortality. 6-month survival and overall patient status were determined via patient contact or chart review. This study is registered with ClinicalTrials.gov, NCT04366921, and is complete.

Findings

We included 3860 patients (2687 [69·7%] were male and 1169 [30·3%] were female; median age 51 years [SD 11]) from 98 centres in 21 countries. In-hospital mortality was 55·9% (n=2158), with 81·2% (n=1752) deaths occurring during ECMO support. More non-survivors had diabetes, hypertension, cardiovascular disease, and renal failure, and required more pre-ECMO inotropes and vasopressors compared with survivors. Median support duration was 18 days (IQR 10–31) for both groups. Factors linked to in-hospital mortality included older age, pre-ECMO renal failure, pre-ECMO vasopressors use, longer time from intubation to ECMO initiation, and complications, including neurological events, sepsis, bowel ischaemia, renal failure, and bleeding. Of the 1702 (44·1%) in-hospital survivors, 99·7% (n=1697) were alive at 6 months follow-up. Many patients at 6 months follow-up had dyspnoea (501 [32·0%] of 1568 patients), cardiac (122 [7·8%] of 1568 patients), or neurocognitive (168 [10·7%] of 1567 patients) symptoms.

Interpretation

Our data for patients undergoing ECMO support for respiratory distress from the second COVID-19 wave onwards confirmed most findings from the first wave regarding patient characteristics and factors correlated to in-hospital mortality. Nevertheless, in-hospital mortality was higher than during the initial pandemic wave while 6-month post-discharge survival remained favourable (99·7%). Persisting post-discharge symptoms confirmed the need for post-ECMO patient follow-up programmes.

Source: Lancet Respiratory Medicine, https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(24)00369-2/abstract?rss=yes

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#Critical #Illness in an #Adolescent with #Influenza A(#H5N1) Virus #Infection

To the Editor:

Highly pathogenic avian influenza A(H5N1) viruses are circulating among wild birds and poultry in British Columbia, Canada.1 These viruses are also recognized to cause illness in humans. Here, we report a case of critical illness caused by influenza A(H5N1) virus infection in British Columbia.

On November 4, 2024, a 13-year-old girl with a history of mild asthma and an elevated body-mass index (the weight in kilograms divided by the square of the height in meters) of greater than 35 presented to an emergency department in British Columbia with a 2-day history of conjunctivitis in both eyes and a 1-day history of fever. She was discharged home without treatment, but cough, vomiting, and diarrhea then developed, and she returned to the emergency department on November 7 in respiratory distress with hemodynamic instability. On November 8, she was transferred, while receiving bilevel positive airway pressure, to the pediatric intensive care unit at British Columbia Children’s Hospital with respiratory failure, pneumonia in the left lower lobe, acute kidney injury, thrombocytopenia, and leukopenia (...). A nasopharyngeal swab obtained at admission was positive for influenza A but negative for A(H1) and A(H3) by the BioFire Respiratory Panel 2.1 assay (BioFire Diagnostics). Reflex testing of the specimen with the Xpert Xpress CoV-2/Flu/RSV plus assay (Cepheid) revealed an influenza A cycle threshold (Ct) value of 27.1. This finding indicates a relatively high viral load for which subtyping would be expected; the lack of subtype identification suggested infection with a novel influenza A virus. Oseltamivir treatment was started on November 8 (Table S2), and the use of eye protection, N95 respirators, and other precautions against droplet, contact, and airborne transmission were implemented.

A reverse-transcriptase–polymerase-chain-reaction (RT-PCR) test specific for influenza A(H5)2 was positive on the day of admission. The patient had signs of respiratory deterioration — chest radiographs were consistent with progression to acute respiratory distress syndrome (...) — which prompted tracheal intubation and initiation of venovenous extracorporeal membrane oxygenation (ECMO) on November 9. Continuous renal replacement therapy was initiated on November 10. Combination antiviral treatment with amantadine (initiated on November 9) and baloxavir (initiated on November 11) was added to ongoing treatment with oseltamivir. Bacterial cultures of blood (samples obtained at admission) and endotracheal aspirate (obtained after intubation) yielded no growth.

Because of concern for cytokine-mediated hemodynamic instability, plasma exchange was performed daily from November 14 through November 16. Serial influenza A–specific RT-PCR tests showed increasing Ct values, which suggested a decline in the viral RNA load in serum and a decline in viral RNA in upper- and lower-respiratory specimens shortly after the initiation of antiviral treatment, with the first negative RT-PCR result for serum obtained on November 16 (...). It is notable that lower-respiratory specimens consistently yielded lower Ct values than upper-respiratory specimens, a finding that suggested higher viral levels in the lower-respiratory tract (...).

Influenza A(H5N1) virus was cultured from respiratory specimens obtained between November 8 and November 12 but not from subsequent respiratory specimens or from any serum specimens (...). No evidence of reduced susceptibility to any of the three antiviral agents used in treatment was observed in serial respiratory specimens by either genomic analysis or phenotypic testing with the NA-Star influenza neuraminidase inhibitor resistance detection kit (ThermoFisher Scientific) (...). The patient’s respiratory status improved, ECMO was discontinued on November 22, and the patient’s trachea was extubated on November 28.

The viral genome sequence obtained from a tracheal-aspirate specimen collected on November 9 (8 days after the onset of symptoms) was reconstructed as described previously.3 The virus was typed as clade 2.3.4.4b, genotype D1.1,4 most closely related to viruses detected in wild birds in British Columbia around the same time (...). Markers of adaptation to humans were detected in the tracheal-aspirate specimen collected on November 9: the E627K mutation was detected (52% allele frequency) in the polymerase basic 2 (PB2) gene product, and analysis of the H5 hemagglutinin (HA) gene yielded ambiguous calls in the codons for amino acid residues E186 (E190 according to H3 mature HA numbering) — 28% allele frequency for E186D — and Q222 (Q226 according to H3 mature HA numbering) — 35% allele frequency for Q222H. The mutations in the H5 HA gene have previously been shown to increase binding to α2-6–linked sialic acids, which act as receptors that facilitate viral entry into cells in the human respiratory tract and enable viral replication.5

Highly pathogenic avian influenza A(H5N1) virus infection acquired in North America can cause severe human illness. Evidence for changes to HA that may increase binding to human airway receptors is worrisome.

Agatha N. Jassem, Ph.D., British Columbia Centre for Disease Control, Vancouver, BC, Canada; Ashley Roberts, M.D., British Columbia Children’s Hospital, Vancouver, BC, Canada; John Tyson, Ph.D., James E.A. Zlosnik, Ph.D., Shannon L. Russell, Ph.D., British Columbia Centre for Disease Control, Vancouver, BC, Canada; Jessica M. Caleta, M.Sc., Public Health Agency of Canada, Winnipeg, MB, Canada; Eric J. Eckbo, M.D., British Columbia Centre for Disease Control, Vancouver, BC, Canada; Ruimin Gao, Ph.D., Taeyo Chestley, Ph.D., Public Health Agency of Canada, Winnipeg, MB, Canada; Jennifer Grant, M.D., British Columbia Centre for Disease Control, Vancouver, BC, Canada; Timothy M. Uyeki, M.D., M.P.H., Centers for Disease Control and Prevention, Atlanta, GA; Natalie A. Prystajecky, Ph.D., British Columbia Centre for Disease Control, Vancouver, BC, Canada; Chelsea G. Himsworth, D.V.M., Ph.D., British Columbia Ministry of Agriculture and Food, Abbotsford, BC, Canada; Elspeth MacBain, M.D., British Columbia Children’s Hospital, Vancouver, BC, Canada; Charlene Ranadheera, Ph.D., Public Health Agency of Canada, Winnipeg, MB, Canada; Lynne Li, M.D., British Columbia Children’s Hospital, Vancouver, BC, Canada; Linda M.N. Hoang, M.D., British Columbia Centre for Disease Control, Vancouver, BC, Canada; Nathalie Bastien, Ph.D., Public Health Agency of Canada, Winnipeg, MB, Canada; David M. Goldfarb, M.D., British Columbia Children’s Hospital, Vancouver, BC, Canada.

Source: New England Journal of Medicine, https://www.nejm.org/doi/full/10.1056/NEJMc2415890

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