Avian influenza history and symptoms: Difference between revisions

Jump to navigation Jump to search
No edit summary
mNo edit summary
Line 1: Line 1:
__NOTOC__
__NOTOC__
{{Avian influenza}}'''For more information about seasonal human influenza virus that is not associated with animal exposure, see [[Influenza]]'''<br><br>
{{Avian influenza}}
'''For more information about seasonal human influenza virus that is not associated with animal exposure, see [[Influenza]]'''
 
{{CMG}}
{{CMG}}



Revision as of 23:43, 23 April 2015

Avian influenza Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Avian influenza from other Diseases

Epidemiology and Demographics

Risk Factors

Natural History, Complications and Prognosis

Diagnosis

History and Symptoms

Physical Examination

Laboratory Findings

Chest X Ray

Other Diagnostic Studies

Treatment

Medical Therapy

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Avian influenza history and symptoms On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Avian influenza history and symptoms

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Avian influenza history and symptoms

CDC on Avian influenza history and symptoms

Avian influenza history and symptoms in the news

Blogs on Avian influenza history and symptoms

Directions to Hospitals Treating Avian influenza

Risk calculators and risk factors for Avian influenza history and symptoms

For more information about seasonal human influenza virus that is not associated with animal exposure, see Influenza

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Highly pathogenic avian influenza (HPAI) Asian H5N1 and low pathogenic avian influenza (LPAI) H7N9 have been responsible for most human illness worldwide to date, including the most serious illnesses and deaths.[1] H5N1 virus infection is associated with a wide range of illness from conjunctivitis only, to influenza-like illness, to severe respiratory illness (e.g. shortness of breath, difficulty breathing, pneumonia, acute respiratory distress, viral pneumonia, respiratory failure) with multi-organ disease, sometimes accompanied by nausea, abdominal pain, diarrhea, vomiting and sometimes neurologic changes (altered mental status, seizures). The reported signs and symptoms of H7N9 virus infection in humans range from conjunctivitis to influenza-like illness (e.g., fever, cough, sore throat, muscle aches) to lower respiratory disease (pneumonia) requiring hospitalization.

History and Symptoms

Most avian influenza viruses do not cause disease in humans. However, some are zoonotic, meaning that they can infect humans and cause disease. The most well known example is the avian influenza subtype H5N1 viruses currently circulating in poultry in parts of Asia and northeast Africa, which have caused human disease and deaths since 1997. Other avian influenza subtypes, including H7N7 and H9N2, have also infected humans. Some of these infections have been very severe and some have resulted in deaths, but the majority of infections have been mild or even subclinical.[2]

H5N1

In many patients, the disease caused by the influenza A(H5N1) virus follows an unusually aggressive clinical course, with rapid deterioration and high fatality. The incubation period for A(H5N1) avian influenza may be longer than that for normal seasonal influenza, which is around 2 to 3 days. Current data for A(H5N1) infection indicate an incubation period ranging from 2 to 8 days and possibly as long as 17 days.[3]

Initial symptoms include high fever, usually with a temperature higher than 38°C, and other influenza-like symptoms (cough or sore throat). Diarrhea, vomiting, abdominal pain, chest pain, and bleeding from the nose and gums have also been reported as early symptoms in some patients. One feature seen in many patients is the development of lower respiratory tract early in the illness. Respiratory distress, a hoarse voice, and a crackling sound on inhalation are commonly observed. Sputum production is variable and sometimes bloody. The course of A(H5N1) infection may be complicated by hypoxemia, multiple organ dysfunction, and secondary bacterial and fungal infections.[4]

H7N9

Current data for A(H7N9) infection indicate an incubation period ranging from 2 to 8 days, with an average of five days.[5] Therefore it is recommended that an incubation period of 7 days be used for field investigations and the monitoring of patient contacts.

The disease caused by the virus is characterized by rapidly progressing severe pneumonia. Common symptoms are not disease specific and those of typical acute respiratory infection, such as fever, cough, and shortness of breath. Complications include the acute respiratory distress syndrome (ARDS), septic shock and multi-organ failure requiring intensive care and mechanical ventilation. A small number of patients with mild clinical illness have been detected through on-going influenza- like illness (ILI) surveillance systems and contact tracing in otherwise healthy children and young adults. Severe illness is more likely to occur in older persons with underlying chronic conditions.

References

  1. "Avian Influenza A Virus Infections in Humans". Text " Avian Influenza (Flu)" ignored (help)
  2. "WHO". WHO. Text " Avian influenza in humans" ignored (help)
  3. Beigel, John H.; Farrar, Jeremy; Han, Aye Maung; Hayden, Frederick G.; Hyer, Randy; de Jong, Menno D.; Lochindarat, Sorasak; Nguyen, Thi Kim Tien; Nguyen, Tran Hien; Tran, Tinh Hien; Nicoll, Angus; Touch, Sok; Yuen, Kwok-Yung; Writing Committee of the World Health Organization (WHO) Consultation on Human Influenza A/H5 (2005-09-29). "Avian influenza A (H5N1) infection in humans". The New England Journal of Medicine. 353 (13): 1374–1385. doi:10.1056/NEJMra052211. ISSN 1533-4406. PMID 16192482.
  4. "WHO". WHO. Text " Avian influenza" ignored (help)
  5. Gao, Hai-Nv; Lu, Hong-Zhou; Cao, Bin; Du, Bin; Shang, Hong; Gan, Jian-He; Lu, Shui-Hua; Yang, Yi-Da; Fang, Qiang; Shen, Yin-Zhong; Xi, Xiu-Ming; Gu, Qin; Zhou, Xian-Mei; Qu, Hong-Ping; Yan, Zheng; Li, Fang-Ming; Zhao, Wei; Gao, Zhan-Cheng; Wang, Guang-Fa; Ruan, Ling-Xiang; Wang, Wei-Hong; Ye, Jun; Cao, Hui-Fang; Li, Xing-Wang; Zhang, Wen-Hong; Fang, Xu-Chen; He, Jian; Liang, Wei-Feng; Xie, Juan; Zeng, Mei; Wu, Xian-Zheng; Li, Jun; Xia, Qi; Jin, Zhao-Chen; Chen, Qi; Tang, Chao; Zhang, Zhi-Yong; Hou, Bao-Min; Feng, Zhi-Xian; Sheng, Ji-Fang; Zhong, Nan-Shan; Li, Lan-Juan (2013-06-13). "Clinical findings in 111 cases of influenza A (H7N9) virus infection". The New England Journal of Medicine. 368 (24): 2277–2285. doi:10.1056/NEJMoa1305584. ISSN 1533-4406. PMID 23697469.

See Also