Krauss et al. (1) use lack of detection of highly pathogenic (HP) H5 clade 2.3.4.4 (henceforth “H5”) influenza A viruses (IAVs) from >22,000 wild bird samples collected in North America in 2014–2015 to argue that HP H5 IAVs disappeared from waterfowl and that unresolved mechanisms restrict emergence and perpetuation of HP IAVs in natural reservoir species. Here we offer an alternative interpret...

Background: Studies have shown that DNA vaccines can induce protective immunity, which demonstrated the high potential of DNA vaccines as an alternative to inactivated vaccines. Vaccines are frequently formulated with adjuvants to improve their release, delivery and presentation to the host immune system. Methods: The H5 gene of H5N1 virus (A/Ck/Malaysia/5858/04) was cloned separately into pcDN...

The emergence in 2009 of a swine-origin H1N1 influenza virus as the first pandemic of the 21st Century is a timely reminder of the international public health impact of influenza viruses, even those associated with mild disease. The widespread distribution of highly pathogenic H5N1 influenza virus in the avian population has spawned concern that it may give rise to a human influenza pandemic. T...

The H5 subtype highly pathogenic avian influenza (HPAI) virus is one of the greatest threats to global poultry industry. To develop broadly protective H5 subunit vaccine, a recombinant consensus HA sequence (rHA) was constructed and expressed in virus-like particles (rHA VLPs) in the baculovirus-insect cell system. The efficacy of the rHA VLPs vaccine with or without immunopotentiator (CVCVA5) ...

Highly pathogenic avian influenza (HPAI) caused by the H5N1 subtype has given rise to serious damage in poultry industries in Asia. The virus has expanded its geographical range to Europe and Africa, posing a great risk to human health as well. For the control of avian influenza, a rapid diagnosis by detecting the causative virus and identifying its subtype is essential. In the present study, a...

Efficient replication of plus-strand RNA viruses requires a 3' proximal core promoter and an increasingly diverse inventory of supporting elements such as enhancers, repressors, and 5' terminal sequences. While core promoters have been well characterized, much less is known about structure-functional relationships of these supporting elements. Members of the genus Carmovirus family Tombusvirida...

In Egypt, ducks kept for commercial purposes constitute the second highest poultry population, at 150 million ducks/year. Hence, ducks play an important role in the introduction and transmission of avian influenza (AI) in the Egyptian poultry population. Attempts to control outbreaks include the use of vaccines, which have varying levels of efficacy and failure. To date, the effects of vaccine ...

The current definitions of high-pathogenicity avian influenza (HPAI), formulated over 10 years ago, were aimed at including viruses that were overtly virulent in in vivo tests and those that had the potential to become virulent. At that time the only virus known to have mutated to virulence was the one responsible for the 1983-84 Pennsylvania epizootic. The mechanism involved has not been seen ...