Influenza (avian and other zoonotic)

                                  Overview

                                  Animal influenza viruses are distinct from human seasonal influenza viruses and do not easily transmit between humans. However, zoonotic influenza viruses - animal influenza viruses that may occasionally infect humans through direct or indirect contact - can cause disease in humans ranging from a mild illness to death.

                                  Birds are the natural hosts for avian influenza viruses. After an outbreak of A(H5N1) virus in 1997 in poultry in Hong Kong SAR, China, since 2003, this avian and other influenza viruses have spread from Asia to Europe and Africa. In 2013, human infections with the influenza A(H7N9) virus were reported in China.

                                  Most swine influenza viruses do not cause disease in humans, but some countries have reported cases of human infection from certain swine influenza viruses. Close proximity to infected pigs or visiting locations where pigs are exhibited has been reported for most human cases, but some limited human-to-human transmission has occurred.

                                  Just like birds and pigs, other animals such as horses and dogs, can be infected with their own influenza viruses (canine influenza viruses, equine influenza viruses, etc.).

                                   

                                  Symptoms

                                  Avian, swine and other zoonotic influenza infections in humans may cause disease ranging from mild upper respiratory infection (fever and cough) to rapid progression to severe pneumonia, acute respiratory distress syndrome, shock and even death.

                                  Gastrointestinal symptoms such as nausea, vomiting and diarrhea has been reported more frequently in A(H5N1) infection. Conjunctivitis has also been reported in influenza A(H7).

                                  Disease features such as the incubation period, severity of symptoms and clinical outcome varies by the virus causing infection but mainly manifests with respiratory symptoms.

                                   

                                  Treatment
                                  Evidence suggests that some antiviral drugs, notably neuraminidase inhibitor (oseltamivir, zanamivir), can reduce the duration of viral replication and improve prospects of survival, however ongoing clinical studies are needed. Emergence of oseltamivir resistance has been reported.

                                   

                                  Publications

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                                  Pandemic Influenza Preparedness Framework: 18-month progress report, 1 January 2020–30 June 2021

                                  The Pandemic Influenza Preparedness (PIP) Framework is a World Health Assembly resolution adopted unanimously by all Member States in 2011. It brings together...

                                  The Pandemic Influenza Pandemic (PIP) Framework's Partnership Contribution (PC) High-Level Implementation Plan II (HLIP II) outlines the strategy...

                                  Pandemic influenza preparedness framework for the sharing of influenza viruses and access to vaccines and other benefits, 2nd ed

                                  The objective of the Pandemic Influenza Preparedness Framework is to improve pandemic influenza preparedness and response, and strengthen the protection...

                                  Pandemic influenza preparedness framework: annual progress report, 1 January - 31 December 2020

                                  The Pandemic Influenza Preparedness (PIP) Framework is a World Health Assembly resolution adopted unanimously by all Member States in 2011. It brings...