The relentless march of a highly pathogenic avian influenza virus(HPAIV)strain,known as H5N1,to become an unprecedented panzootic continues unchecked.The leap of H5N1 clade 2.3.4.4b from Eurasia and Africa to North Am...The relentless march of a highly pathogenic avian influenza virus(HPAIV)strain,known as H5N1,to become an unprecedented panzootic continues unchecked.The leap of H5N1 clade 2.3.4.4b from Eurasia and Africa to North America in 2021 and its further spread to South America and the Antarctic have exposed new avian and mammalian populations to the virus and led to outbreaks on an unrivaled scale.The virus has infected wild birds across vast geographic regions and caused wildlife deaths in some of the world's most biodiverse ecosystems.展开更多
Highly pathogenic avian influenza(HPAI)H5N1 hemagglutinin clade 2.3.4.4b was detected in the United States in 2021.These HPAI viruses caused mortality events in poultry,wild birds,and wild mammals.On March 25,2024,HPA...Highly pathogenic avian influenza(HPAI)H5N1 hemagglutinin clade 2.3.4.4b was detected in the United States in 2021.These HPAI viruses caused mortality events in poultry,wild birds,and wild mammals.On March 25,2024,HPAI H5N1 clade 2.3.4.4b was confirmed in a dairy cow in Texas in response to a multi-state investigation into milk production losses.1 Over 200 positive herds were identified in 14 U.S.states.The case description included reduced feed intake and rumen motility in lactating cows,decreased milk production,and thick yellow milk.2,3 The diagnostic investigation revealed viral RNA in milk and mammary tissue with alveolar epithelial degeneration and necrosis and positive immunoreactivity of glandular epithelium.A single transmission event,likely from birds,was followed by limited local transmission and onward horizontal transmission of H5N1 clade 2.3.4.4b genotype B3.13.4 We sought to experimentally reproduce infection with genotype B3.13 in Holstein yearling heifers and lactating cows.Heifers were inoculated by aerosol respiratory route and cows by intramammary route.Clinical disease was mild in heifers,but infection was confirmed by virus detection,lesions,and seroconversion.Clinical disease in lactating cows included decreased rumen motility,changes to milk appearance,and production losses.Infection was confirmed by high levels of viral RNA detected in milk,virus isolation,lesions in mammary tissue,and seroconversion.This study provides the foundation to investigate additional routes of infection,pathogenesis,transmission,and intervention strategies.展开更多
BACKGROUND:The 2009 H1N1 influenza A virus was first identified in April 2009 and rapidly evolved into a pandemic. Recipients of solid-organ transplants have a higher risk for severe infection because of immunosuppres...BACKGROUND:The 2009 H1N1 influenza A virus was first identified in April 2009 and rapidly evolved into a pandemic. Recipients of solid-organ transplants have a higher risk for severe infection because of immunosuppression.There are limited reports of 2009 H1N1 influenza in liver transplant recipients,especially in China. METHODS:We present a case of a 48-year-old male liver transplant recipient with 2009 H1N1 influenza A virus.He received therapy for acute rejection after transplantation and was confirmed with H1N1 virus infection. RESULTS:The patient was started on oseltamivir(75 mg, orally twice daily)and had a benign hospital course,with defervescence and resolution of symptoms within 72 hours. The follow-up chest radiograph after discharge was normal. CONCLUSIONS:The 2009 H1N1 influenza in this hospitalized transplant recipient was relatively mild,and prolonged viral shedding was not noted.Oseltamivir can be a valid measure in immunocompromised individuals.展开更多
Objective To analyze the clinical features,therapeutic management and risk factors for mortality of patients with severe novel A(H1N1)influenza in Shanghai,China.Methods All patients were diagnosed by influenza A(H1N1...Objective To analyze the clinical features,therapeutic management and risk factors for mortality of patients with severe novel A(H1N1)influenza in Shanghai,China.Methods All patients were diagnosed by influenza A(H1N1)virus mRNA detection.Chest CT scan,routine blood,hepatic function,humoral and cellular immunity,sputum smears,and sputum cultures were performed.Logistic analysis was applied to identify risk factors for mortality.Results Total of 68 patients were enrolled in this study,the primary clinical symptoms including cough(66,97.1%),expectoration(41,60.3%),and polypnea(41,60.3%).Altogether,37(54.4%)and 11(16.2%)patients were infected with bacterial and fungal,respectively.CT scan demonstrated that 67(98.6%)patients had pneumonia.Oxygen therapy,oseltamivir,antibiotic and antifungal drugs were performed in 68(100%),66(97.1%),39(57.4%),and 11(16.2%)patients,respectively.Finally,4 of 68 patients died.Logistic analysis demonstrated that there was a significant correlation between the percentage of neutrophils and mortality before therapy and direct bilirubin content and mortality after therapy,respectively.Conclusions Patients with severe H1N1 influenza were susceptible to bacterial and/or fungal infection.The risk factors for mortality may be associated with pre-therapeutic neutrophil percentage and post-therapeutic direct bilirubin content.展开更多
文摘The relentless march of a highly pathogenic avian influenza virus(HPAIV)strain,known as H5N1,to become an unprecedented panzootic continues unchecked.The leap of H5N1 clade 2.3.4.4b from Eurasia and Africa to North America in 2021 and its further spread to South America and the Antarctic have exposed new avian and mammalian populations to the virus and led to outbreaks on an unrivaled scale.The virus has infected wild birds across vast geographic regions and caused wildlife deaths in some of the world's most biodiverse ecosystems.
文摘Highly pathogenic avian influenza(HPAI)H5N1 hemagglutinin clade 2.3.4.4b was detected in the United States in 2021.These HPAI viruses caused mortality events in poultry,wild birds,and wild mammals.On March 25,2024,HPAI H5N1 clade 2.3.4.4b was confirmed in a dairy cow in Texas in response to a multi-state investigation into milk production losses.1 Over 200 positive herds were identified in 14 U.S.states.The case description included reduced feed intake and rumen motility in lactating cows,decreased milk production,and thick yellow milk.2,3 The diagnostic investigation revealed viral RNA in milk and mammary tissue with alveolar epithelial degeneration and necrosis and positive immunoreactivity of glandular epithelium.A single transmission event,likely from birds,was followed by limited local transmission and onward horizontal transmission of H5N1 clade 2.3.4.4b genotype B3.13.4 We sought to experimentally reproduce infection with genotype B3.13 in Holstein yearling heifers and lactating cows.Heifers were inoculated by aerosol respiratory route and cows by intramammary route.Clinical disease was mild in heifers,but infection was confirmed by virus detection,lesions,and seroconversion.Clinical disease in lactating cows included decreased rumen motility,changes to milk appearance,and production losses.Infection was confirmed by high levels of viral RNA detected in milk,virus isolation,lesions in mammary tissue,and seroconversion.This study provides the foundation to investigate additional routes of infection,pathogenesis,transmission,and intervention strategies.
基金supported by a grant from the National Key Technology R&D Program of China(2008ZX10002-26)
文摘BACKGROUND:The 2009 H1N1 influenza A virus was first identified in April 2009 and rapidly evolved into a pandemic. Recipients of solid-organ transplants have a higher risk for severe infection because of immunosuppression.There are limited reports of 2009 H1N1 influenza in liver transplant recipients,especially in China. METHODS:We present a case of a 48-year-old male liver transplant recipient with 2009 H1N1 influenza A virus.He received therapy for acute rejection after transplantation and was confirmed with H1N1 virus infection. RESULTS:The patient was started on oseltamivir(75 mg, orally twice daily)and had a benign hospital course,with defervescence and resolution of symptoms within 72 hours. The follow-up chest radiograph after discharge was normal. CONCLUSIONS:The 2009 H1N1 influenza in this hospitalized transplant recipient was relatively mild,and prolonged viral shedding was not noted.Oseltamivir can be a valid measure in immunocompromised individuals.
基金supported by a grant-in-aid from the state administration of Traditional Chinese Medicine of China for the infectious disease prophylaxis and treatment through grant number 200907001-2
文摘Objective To analyze the clinical features,therapeutic management and risk factors for mortality of patients with severe novel A(H1N1)influenza in Shanghai,China.Methods All patients were diagnosed by influenza A(H1N1)virus mRNA detection.Chest CT scan,routine blood,hepatic function,humoral and cellular immunity,sputum smears,and sputum cultures were performed.Logistic analysis was applied to identify risk factors for mortality.Results Total of 68 patients were enrolled in this study,the primary clinical symptoms including cough(66,97.1%),expectoration(41,60.3%),and polypnea(41,60.3%).Altogether,37(54.4%)and 11(16.2%)patients were infected with bacterial and fungal,respectively.CT scan demonstrated that 67(98.6%)patients had pneumonia.Oxygen therapy,oseltamivir,antibiotic and antifungal drugs were performed in 68(100%),66(97.1%),39(57.4%),and 11(16.2%)patients,respectively.Finally,4 of 68 patients died.Logistic analysis demonstrated that there was a significant correlation between the percentage of neutrophils and mortality before therapy and direct bilirubin content and mortality after therapy,respectively.Conclusions Patients with severe H1N1 influenza were susceptible to bacterial and/or fungal infection.The risk factors for mortality may be associated with pre-therapeutic neutrophil percentage and post-therapeutic direct bilirubin content.
