A fatal case caused by novel H7N9 avian influenza A virus in China

Yang, Feifei; Wang, Jiali; Jiang, Lin; Jin, Jialin; Shao, Lingyun; Zhang, Ying; Zhang, Jiming; Weng, Xinhua; Chen, Shu; Zhang, Wenhong

To date (April 7th, 2013), a total of 21 cases have been laboratory confirmed with influenza A (H7N9) virus in China, including 6 deaths, 12 severe cases and 3 mild cases. 5 An inter-government task force has been formally established, the animal health sector has intensified investigations into the possible sources and reservoirs of the virus. However no definite history of contact with livestock was found in this case. The patient also did not feed or eat poultry at households. Some other confirmed cases had close contact with poultry or with associated environment. It is interesting to note that the virus has also been found in a pigeon in a market in Shanghai. It is unclear how this case was infected by H7N9 AIV, similar to some other cases without known recent close contact with birds or poultry. However, influenza A H7 viruses are a group of influenza viruses that normally circulate among birds and the influenza A (H7N9) virus is one subgroup among the larger group of H7 viruses. 6 Although the patient denied close contact with poultry, H7N9 virus was detected among poultry at local market. The most likely source of the virus in this case seems to be from the environment or food contaminated with this novel virus. The emergence of H7N9 AIV infections in humans suggests the avian influenza virus evolves to achieve adaptations including the ability to bind to mammalian cells and to break the species barrier. Fortunately, among close contacts of this case, the patient's husband was pyretic with a temperature of 38 6 C, but negative for H7N9 AIV detection and recovered soon, indicating no evidence of human-to-human transmission up to this point. At this time there is no evidence of ongoing human-to-human transmission. The possibility of animal-to-human transmission is being investigated, as is the possibility of person-to-person transmission.