BioBoard

Selective isolation of avian influenza virus from cloacal samples containing mixed infection of avian influenza and Newcastle disease viruses

Between 2 December 2023 and 15 March 2024, highly pathogenic avian influenza (HPAI) A(H5) outbreaks were reported in domestic (227) and wild (414) birds across 26 countries in Europe. Compared to previous years, although still widespread, the overall number of HPAI virus detections in birds was significantly lower, among other reasons, possibly due to some level of flock immunity in previously affected wild bird species, resulting in reduced contamination of the environment, and a different composition of circulating A(H5N1) genotypes. Most HPAI outbreaks reported in poultry were primary outbreaks following the introduction of the virus by wild birds. Outside Europe, the majority of outbreaks in poultry were still clustered in North America, while the spread of A(H5) to more naïve wild bird populations on mainland Antarctica is of particular concern. For mammals, A(H5N5) was reported for the first time in Europe, while goat kids in the United States of America represented the first natural A(H5N1) infection in ruminants. Since the last report and as of 12 March 2024, five human avian influenza A(H5N1) infections, including one death, three of which were clade 2.3.2.1c viruses, have been reported by Cambodia. China has reported two human infections, including one fatal case, with avian influenza A(H5N6), four human infections with avian influenza A(H9N2) and one fatal case with co-infection of seasonal influenza A(H3N2) and avian influenza A(H10N5). The latter case was the first documented human infection with avian influenza A(H10N5). Human infections with avian influenza remain rare and no sustained human-to-human infection has been observed. The risk of infection with currently circulating avian H5 influenza viruses of clade 2.3.4.4b in Europe remains low for the general population in the EU/EEA. The risk of infection remains low to moderate for those occupationally or otherwise exposed to infected animals.

Background: Avian influenza is an infectious disease of birds caused by A strain of the influenza virus. Some strains are highly contagious causing rapidly a fatal disease in poultry. The strains are known as HPAI (highly pathogenic avian influenza). Until year 1997, direct transmission of HPAI to humans was not known. During the last large outbreak of HPAI H5N1 in South-East Asia in 2004, the virus was transmitted to relatively low number of humans with a high mortality rate. The measures were taken to contain the outbreak of HPAI H5N1 in South-East Asia. However, there is a possibility that the disease might spread to other parts of the world. There is also a certain degree of concern regarding more intensified spread from birds to humans and frequent interhuman transmission. Conclusions: In our paper, we present the recommended infectious control precautions in health care facilities with possible or confirmed case of HPAI H5N1, control measures in case of outbreak of HPAI in poultry in Slovenia and recommendations for travellers to the affected areas.

Background: An outbreak of highly pathogenic avian influenza (HPAI) H5N1 virus in Thailand was first reported in 2004. To date, electron micrographs demonstrating the morphology of HPAI H5N1 virus particle are quite limited. Objective: To demonstrate the morphology of HPAI H5N1 virus particles, avian influenza viruses with low pathogenicity, seasonal influenza viruses, and H5N1 structural components in infected cells. The M amino acid residues that might affect the viral morphology were also analyzed. Methods: Electron micrographs of negatively-stained virus particles and positively-stained thin sections of the HPAI H5N1 virus infected cells were visualized under a transmission electron microscope. M amino acid sequences of the study viruses were retrieved from the GenBank database and aligned with those of reference strains with known morphology and residues that are unique for the morphological type of the virus particles. Results: Morphologically, three forms of influenza virus particles, spherical, regular, and irregular rods, and long filamentous particles, were demonstrated. However, the spherical form was the most predominant morphological type and accounted for more than 80% of the virus populations examined. In addition, the viral entry and exit steps including incomplete particles in infected Madin-Darby canine kidney cells were visualized. Our analyses did not find any M amino acid residues that might influence the viral morphology. Conclusion: Of all virus isolates studied, we demonstrated that the spherical particles were the major population observed regardless of virus subtype, host of origin, virus virulence, or passage history. Our study suggested that the morphology of influenza virus particles released, might not be strongly influenced by M gene polymorphism. Keywords: Electron micrographs, highly pathogenic avian influenza H5N1 virus, influenza virus, low pathogenic avian influenza virus, M amino acid sequence, virus morphology

Elements of a flu pandemic

AUSTRALIA – Second-Generation Diagnostic Achieves 98% Accuracy in Detecting Early Stage Ovarian Cancers AUSTRALIA – New Center Brings Australian and Chinese Researchers Together to Fight Infectious Diseases AUSTRALIA – Co-developing New Treatment Guidelines for Melanoma AUSTRALIA – Australia Leads World's First Global Effort to Improve Genetic Disorders Diagnosis CHINA – China Bans Illegal Food Additives to Reinforce Food Safety Control CHINA – China Steps Up Tighter Inspection in Food Safety CHINA – WHO and China to Do More for Chinese with Hearing Impairment CHINA – First TCM Drug for Arrhythmia CHINA – First Human-Human Transmission of Tick-Borne Disease Reported in China CHINA – Bird Flu Found in Chickens in Eastern China CHINA – First Bird Flu Death Reported for 2009, No Bird-flu Outbreak HONG KONG – Hong Kong Alerts New Bird Flu Outbreak INDIA – India Also Confirmed Bird Flu Incidence INDIA – India Plans 20 More Biotech Parks for Life Sciences Research KOREA – An Economic Share in Medical Tourism Market JAPAN – Brain Tissues Made from Stem Cells NEW ZEALAND – Newly Merged Research Institute Leverage Greater Synergy NEW ZEALAND – Kiwi's Green Plastic Well-Acclaimed in International Awards NEW ZEALAND – Sea Sponge Indigenous to NZ Could Reduce Chemo Side Effects PHILIPPINES – Ebola-Reston Virus Jumped Species SINGAPORE – Human Sewage, the Potential Source of Clean Energy SINGAPORE – No More Heart-stopping Incidents for Heart Patients SINGAPORE – China Milk Products Get All-Clear from Singapore SINGAPORE – Discovery of New Properties in Imidazolium Salts Yield Multi Applications SINGAPORE – S'pore Ranked World's Most Prolific for Eye Research Per Capita SINGAPORE – Outdoor Sun Reduces Incidence of Myopia in Children TAIWAN – University Hospital in Taiwan Collaborates with Neuralstem VIETNAM – Return of Bird Flu, Vietnam Runs High Risk of Human Infection VIETNAM – Conjoined Twins Successfully Separated VIETNAM – Rise in Off-Season Dengue Fever Cases NORTH AMERICA – Epilepsy Drugs Prescription to Carry Suicide Risk Warning NORTH AMERICA – U.S. Doctors Succeeded Near-total Face Transplant NORTH AMERICA – Vaccinating Pacific Girls against Cervical Cancer NORTH AMERICA – Manipulating Love and Emotions by Spray EUROPE – Cambridge Pips Oxford in Research EUROPE – Adapting Car Manufacturing Technology to Produce Synthetic Bone Implants EUROPE – Dioxin-tainted Irish Pork Products Recalled

We conducted an epidemiologic investigation to determine the source of infection on an avian influenza (H5N1) case who returned from Guangzhou, in Hong Kong. Data related to epidemiologic investigation, medical observation on close contacts, Syndromic Surveillance on poultry salesmen, emergency monitoring, detection of the samples, source tracing on potential Avian influenza virus (H5, H7, H9) infected people, situation on environment pollution by avian influenza virus in the markets etc. were gathered. The determination of infection source was through comparing the different genes between the case and positive environmental samples. The infected case witnessed the procedure of how a live duck was killed, in market A in Guangzhou during May 17(th) to 19(th). The case was diagnosed as respiratory tract infection in 2 Third-grade-Class A hospitals in Guangzhou on May 23(th) and 24(th). The diagnosis was made as Avian influenza cases on May 26(th) after going back to Hong Kong. 23 close contacts and 34 markets poultry salesmen did not show any ILI related symptoms. However, 2 poultry salesmen from the markets nearby the place where the Avian influenza case stayed, were detected having positive H9 avian influenza antibody, with the H9 positive rate as 6.06% (2/33). Among the environmental samples in the 2 markets nearby home of the patient, chopping block was found to have carried H5, with positive rate as 9.8% (5/51) while poultry cage was found to carry H9, with the positive rate as 2.0% (1/51). A H5 positive sample was found with clade 2.3.2.1, same to the case, from a chopping block at the market B where the sources of poultry was the same as market A. The source of infection seemed to come from the markets in Guangzhou, that calling for the strengthening of poultry market management, for avian influenza prevention. History related to contact of poultry should be gathered when a diagnosis of respiratory tract infection was made. Timely sampling and testing should be made to improve the sensitivity of diagnosis.

A United States network of laboratories, initially created to protect the health of US service personnel by doing local research and disease surveillance, has become a major public health presence in the developing countries where it operates.

Evidence for avian H9N2 influenza virus infections among rural villagers in Cambodia

Reassortment ability of the 2009 pandemic H1N1 influenza virus with circulating human and avian influenza viruses: Public health risk implications

Influenza A viruses cause pandemics at sporadic intervals. Pandemic viruses can potentially be introduced into the human population through in toto transfer of an avian influenza virus or through reassortment between avian and human strains. Pigs are believed to play a central role in the creation of pandemic viruses through reassortment because of their susceptibility to infection with both avian and human influenza viruses. However, we recently found that a human-lineage H3N2 influenza virus was highly restricted in its ability to infect pigs after intranasal inoculation. We hypothesized that this restricted infectivity phenotype was controlled by the hemagglutinin (HA) and neuraminidase (NA). To test this, we infected pigs with reverse genetics-created HA plus NA reassortant viruses. Specifically, introduction of the HA and NA genes of a contemporary H3N2 swine virus into the genetic background of the wholly human virus resulted in a significant increase in virus shedding and pathogenicity. These data indicate that the HA/NA can play important roles in controlling human influenza virus infectivity in pigs. The results further support the premise that a barrier exists to human influenza virus infection in pigs, which may limit the role of pigs in pandemic virus creation through reassortment of human and avian influenza viruses.

Highly Pathogenic Avian Influenza (HPAI) is a viral disease affecting the digestive, nervous and respiratory systems of all domestic and wild birds that is characterized by respiratory, reproductive, digestive and/or nervous signs with high morbidity and mortality. Following the first report of Avian Influenza (AI) in Nigeria in January 2006 and its subsequent confirmation in February 2006, this study was designed to Retrospectively Review the Spatio-Temporal spread of HPAI in and around Maiduguri, Borno State, Nigeria. Out breaks were recorded from six (6) farms within Maiduguri and its environs, the index case of AI in Maiduguri was noticed on the 11th November, 2006 and was reported on the 13th November, 2006. Subsequent transmission from the index case could have been through aerosol or contaminated dust in the direction of wind flow as occasioned by the prevailing harmattan period which coincides with the outbreak period between November 2006 and January 2007. An age-specific mortality rate of 33.7% was recorded among birds of age group 0- 30 weeks, while 53.1% among the age group 31-60 weeks and 44.1% was recorded among adult birds of unknown age group. It is recommended that there should be improved management practices, which include strict enforcement of biosecurity measures to reduce human and fomite contacts risks that could occur without observing or breach of biosecurity protocols. Improve litter and other poultry waste management, exclusion of other animal species on poultry farms, and institution biosecurity against risks from neighbourhood farms’ activities.

Farming practices, long-held lifestyle traditions and poverty-line economics all make recent outbreaks of avian flu in Asia a far bigger global public health threat than westward spread of disease into Europe's poultry flocks. For many rural Asian communities, backyard chickens and very small-scale poultry farms are part of landscape. Children play in same yard where household's flock scratch and where chickens that die are typically eaten in order not to waste a valuable source of protein. Every infection of poultry has serious consequences for farmers concerned. Flocks must be culled in a wide radius around area of infection and every person in contact with infected live or dead poultry is at risk of contracting disease. Whilst most western Europeans would get no closer to poultry than peeling away shrink-wrap cover on a pack of supermarket chicken breasts, in Asia most of 67 confirmed deaths from H5N1 avian flu virus have been attributed to direct contact with infected birds, such as slaughter, defeathering, gutting and preparation of chicken and duck. All 130 known human cases of H5N1 have occurred in Asia. In Asia, bird flu outbreaks have been reported over last two years in Cambodia, China, Indonesia, Japan, Kazakhstan, Lao People's Democratic Republic, Malaysia, Thailand and Viet Nam, latter having borne brunt of human infections with 42 WHO-confirmed deaths out of 92 cases since December 2003. Many governments in region are posed with a dilemma over how much scarce public funds should be poured into fight against avian flu. Governments in region have been making efforts to educate population about preventive and surveillance measures, but misconceptions abound about disease, both in poultry and humans. Education campaigns in affected countries are still not getting through to individuals most at risk. Common misconceptions that owners of poultry have include mistaken belief that it won't happen to them, that chickens frequently fall sick and that this time is no more serious than any other time, according to Peter Cordingley, WHO's spokesman for Western Pacific Region, in Manila. Worse than any misconceptions, though, is continuing ignorance in Asia, fact that after two years people still know so little about risky practices. The latest case in Thailand confirmed by WHO was a woman who apparently cleaned out muck from a poultry shed where her husband's chickens had died mysteriously, and this was 50 km or so from Bangkok, he said. Dangerous misconceptions also exist at government level including the belief early on by some governments that outbreaks could be covered up and fixed, thus protecting poultry industry without endangering public health and that vaccinating poultry is a quick, inexpensive and effective way of preventing or responding to outbreaks. Vaccination may stop spread of virus but does nothing to eliminate it. Culling is only option, backed up, where appropriate, by vaccinating, said Cordingley. China, where H5N1 avian flu originated, is grappling with a resurgence of disease among poultry and has confirmed first two human cases of infection with virus on 17 November. National government policy is at odds with what happens at grassroots level because of patchy reporting at local level of outbreaks elsewhere in country. Local level officials also fear incurring ire of their superiors by being open about suspected or confirmed outbreaks and are reluctant to deal with economic consequences of any decision to announce an outbreak and cull poultry. There has to be even greater public awareness. Even though bird flu is not new to China and has been widely reported over last two years, news of every outbreak does not reach everyone and one of biggest dangers is that this might lead to a sense of complacency, said Roy Wadia, WHO's spokesman in China. …

Influenza A virus continue to cause widespread morbidity and mortality. The unprecedented spread of highly pathogenic avian influenza virus subtype H5N1 in Egypt is threatening poultry and public health systems. Effective diagnosis and control management are needed to control the disease. To this end, polyclonal antibodies (PAbs) were developed against the H5N1 avian influenza virus (AIV) and implemented an enzyme-linked immunosorbent assay (ELISA) to detect the H5 viral antigen. A group of rabbits was immunized with viral vaccine (H5N1) therefore, purifiedantibodies from rabbit serum, which secrete immunoglobulin G (IgG) was served as the detector antibody after conjugation with horse radish peroxidase and fluorescent isothiocyanate (FITC). The reactivity of the obtained peroxidase and fluorescent conjugated PAb of influenza virus revealed that they are specifically recognized H5N1 virus antigen. Specimens containing AIV subtypes collected from different Governments in Egypt yielded specific and strong signals with hemagglutination test. The detection limit of ELISA using the prepared peroxidae conjugated PAbs was 1:100000, while using fluorescent conjugated PAb was 1:10000. Reconstituted clinicalsamples consisting of H5 AIVs mixed with pharyngeal-tracheal mucus from healthy chickens also yielded positive signals in ELISA, and the results were confirmed using reference virus antigens. This investigation enhanced the usage of these PAbs in the surveillance and diagnosis of H5N1 AIV in Egypt. Key words: Avian influenza virus, H5N1, fluorescent antibody enzyme-linked immunosorbent assay (ELISA) technique, polyclonal antibodies.

Avian influenza viruses of the H5 and H7 hemagglutinin subtypes, and Newcastle disease virus (NDV), are important pathogens in poultry worldwide. Specifically, the highly pathogenic H5N1 avian influenza virus is a particular threat because it has now occurred in more than 40 countries on several continents. Inasmuch as most chickens worldwide are vaccinated with a live NDV vaccine, we embarked on the development of vaccine prototypes that would have dual specificity and would allow a single immunization against both avian influenza and Newcastle disease. Using reverse genetics, we constructed a chimeric avian influenza virus that expressed the ectodomain of the hemagglutinin-neuraminidase gene of NDV instead of the neuraminidase protein of the H5N1 avian influenza virus. Our second approach to creating a bivalent vaccine was based on expressing the ectodomain of an H7 avian influenza virus hemagglutinin in a fusogenic and attenuated NDV background. The insertion into the NDV genome of the foreign gene (containing only its ectodomain, with the transmembrane and cytoplasmic domains derived from the F protein of NDV) resulted in a chimeric virus with enhanced incorporation of the foreign protein into virus particles. A single immunization of chickens with this improved vaccine prototype virus induced not only a 90% protection against an H7N7 highly pathogenic avian influenza virus, but also complete immunity against a highly virulent NDV. We propose that chimeric constructs should be developed for convenient, affordable, and effective vaccination against avian influenza and Newcastle disease in chickens and other poultry.