The Incubation Period of the Bird Flu

Avian influenza is caused by type A strains of the influenza virus. The contraction of the strain occurs worldwide, and is harbored by wild migratory birds as well as poultry, before passing on to humans.

Origin of Avian Influenza

• Infected birds should be immediately quarantined and culled. The carcasses should be incinerated or buried securely.

  Avian influenza is harbored within the intestines of migratory fowl and occasionally transmitted to poultry. The majority of wild bird populations exhibit no ill-effects from the virus, and typically, avian influenza merely sickens poultry. In rare cases, a more lethal strain is expressed, and typically causes near-100 percent mortality in infected birds in less than 48 hours of onset of the symptoms.

  Infected birds may occasionally transmit the disease to humans. Human-to-human transmission of avian influenza is almost nonexistent as of 2010.

Transmission to Humans and Incubation Period

• Many migratory birds typically rest in or near wetlands. The influenza residing among their gut flora is then transmitted through their feces.

  Avian influenza has among the longest incubation periods of all strains. It can range from 7 to 14 days in most healthy adults, and up to 21 days in children. However, transmission to humans is considered extremely rare.

Symptoms

• Health officials worldwide monitor influenza outbreaks and watch for signs of new strains or increased transmission rates among known strains.

  Avian Influenza exhibits most "normal" flu-like symptoms. These include high fever, diarrhea, vomiting, chest pain, and bleeding from the nose and gums as initial symptoms. However, patients may only exhibit a number of these symptoms.

  H5N1 is the current strain of avian influenza, as of 2010, and is an extremely aggressive form.