عبدالحمید شوشتری

Waterfowls are one of the hosts for Avian influenza virus (AIV) H4 subtypes. In fact, the importance of domestic ducks as reservoirs in the distribution of this virus has been previously proven. Also, the live poultry market could be a significant place in spreading and transmission of influenza virus among the birds and animals. Identification and molecular determination of HA and NA genes of the H4N2 avian influenza virus was isolated from this group of birds in live bird markets of Iran. From 962 cloacal samples, collected from domestic ducks and geese, the NA and HA genes sequences revealed the emergence of this virus in Iran for the first time. Phylogenetic analyses of the HA gene showed high homology to the Eurasian lineage of H4N6. On the other hand, the cleavage site of the HA genes showed a PEKQTR/GLF motif, an indicator of LPAI. Also, the NA gene showed high homology to those belonging to AIV N2 subtype. This is the first study regarding the detection and identification of AIV H4 subtypes from domestic ducks in Iran. It recommends a continuous monitoring of the avian influenza viruses in Iran in order to study the evolution and identify new strains with pandemic potential because such information will be helpful in controlling of the disease.

During the past two decades, the highly pathogenic avian influenza H5N1 virus has received considerable attention due to its zoonotic and mutative features. Purpose of the leading study is molecular and phylogenetic characteristics of hemagglutinin (HA) gene of H5N8 strain identified in Meighan wetland of Arak city, Markazi province were investigated. For this purpose, samples were inoculated with embryonic eggs of 14-10 days and after extraction of allantoic fluid and RNA extraction and PCR and sequencing of genes, phylogenetic trees were drawn by Mega7 program and molecular properties including Cleavage site, Glycosylation site, Antigenic site, Receptor Binding site and HA gene-related mutations were investigated. Based on the analysis of the amino acid sequence of the HA genes, the cleavage site of the gene includes the PLREKRRKR / GLF polybasic amino acid motif, which is a characteristic of highly pathogenic influenza viruses. The HA gene of two viruses had T156A, S123P, S133A mutations associated with the increased mammalian sialic acid binding. Phylogenetic analysis of the HA gene of the virus studied in this study indicated the classification of this virus in the 2.3.4.4 b Clade. It seems that the introduction of these H5N8 HPAI strains in Iran probably occurred through the West Asia-East African flyway by wild migratory aquatic birds.

Avian influenza (AI) is one of the most important respiratory diseases in the poultry industry that causes huge economic impacts and plays an important role in public health. H9N2 Avian Influenza Virus (H9N2 AIV) has a broad circulation and causes endemic infections in the poultry industry of the country.

A cohort study was conducted from July 2016 to November 2017 in broiler chicken farms of Qazvin Province, Iran to detect H9N2 AIV infection determinants in broiler chicken farms.

Sixteen out of 34 units that were included in the study had positive PCR results. Some variables such as “type of fence around the unit”, “biosecurity”, “cooling system status”, “mean maternal antibody titers”, “location height”, “proximity to public traffic lanes” and “number of units within a radius of 1 km” had significant effects on the infection occurrence in poultry units according to univariate statistical analyses (P<0.05). However, only two of them (“biosecurity” and “cooling system status”) were statistically significant in multi-variable analyses (P<0.05).

Biosecurity measures should be implemented more seriously and strictly in broiler farms to reduce the impact of H9N2 AIV infection.

Avian Influenza is an acute and contagious disease of humans and animals, an agent of Orthomyxoviridae family. H9N2 subtype of avian influenza virus (AIVs) is one of the main problems of poultry industry in Iran. The aim of study was to investigate the status of domestic poultry contamination and identifying the hemagglutinin gene of H9N2 isolates in northern providences of Iran.This cross-sectional study was carried out in rural population of Gilan, Mazandaran and Golestan provinces from 1393 to 1394.The sera and cloacal swabs were sampled and tested, using a haemagglutination inhibition test and reverse transcriptase polymerase chain reaction respectively. The RNA was extracted, HA and NA genes was proliferated, using; two pairs of full-open-reading frame universal primer pairs, Titan one step tube RT-PCR system (Roche). A total of 70 villages and 993 birds; (Mazandaran province, 20 villages with 276 birds , Gilan province, 20 villages, with 347 birds and Golestan province, 30 villages with , 370 birds) were sampled. The sera sample of 67 villages (96%) out of 70 and 557 birds (56%) out of 993 were positive. The only H9N2 subtype was isolated of swab sample named A / chicken / Iran / RZ18 / 2014.Both HA and NA genes were common close to Iran / Markazi / 2014 and Iran / MMV9- 2013 isolate. The results reveal a high level of circulation of H9N2 influenza viruses in domestic poultry in the northern provinces of Iran.

Avian influenza is one of the most important diseases both economically and from a public health viewpoint.

To investigate the serological and molecular prevalence of AI-H9N2 in live bird markets, bird gardens, parks and zoos.

This cross-sectional study was conducted from August to December 2016.  In each unit, 40 blood samples from different bird species and 60 cloacal samples from waterfowl (ducks and geese) were taken. All sera samples were tested by HI for detection of antibodies against H9N2 virus. The birds with sera titer =>4 (log2) and units with at least one positive bird were considered as positive. Swab samples were tested by RT-PCR method using two pairs of primers to detect M and H9 gene of H9N2 virus.

2638 sera samples from birds in 127 units in 22 provinces and 3001 swab samples from duck and goose were taken. 73 units out of 127 (57.48 %; 95 % confidence interval, 66.2 % - 48.4 %) and 720 birds from a total of 2638 birds (27.29 %: 95 % confidence interval, 29.6 % - 25.6 %) were sero-positive. Among the bird species, the highest seroprevalence was 47.6 % and 45.3 % in turkey and chicken, respectively and the lowest seroprevalence was 13.8 % and 16.3 % for ducks and geese, respectively. 39 pooled samples from 18 units (14.75 %) were positive.

The results of this study showed high prevalence and circulation of avian influenza H9N2 viruses among poultry in these markets. Organizing the markets by improving the health and biosecurity of the markets, and it is necessary to educate the people and continuously surveillance the birds that offered in the markets to control the disease.

Rural poultry like commercial poultries are susceptible to most of infectious diseases. In addition, by increasing the density of poultry farming, the probability of disease occurrence has been increased. Among the most important diseases, Newcastle disease has most of importance. Newcastle disease is endemic in Iran, and causes incidence of outbreaks among commercial and rural poultries, every year. The present study is conducted with the objective of figuring out the prevalence status and virus circulation among rural poultries of Northern provinces of Iran. In the study, 70 villages in 3 provinces (20 villages in Mazandaran, 20 villages in Golestan and 30 villages in Gilan Province) and a total of 1374 birds (600 birds in Mazandaran, 400 birds in Golestan, 374 birds in Gilan province) were sampled. A village considered as epidemiological unit. In the study, birds of 67 villages (96%) were found positive ( presence of antibodies against NDV) including Golestan Province, 28 villages (93.3%), Mazandaran Province, 19 villages (95%) and 20 villages of Gilan province (100%) Moreover, out of 1374 birds, 616 (45%) of them were seropositive against NDV. According to the results of this study, the rate of titer is very high in both levels of villages and level of birds. Such high rate of titer is indicative of continuous exposures of rural poultry of the mentioned provinces to Newcastle virus and high virus circulation rate of these viruses in the studied provinces.

Infectious bronchitis is a highly contagious disease which may cause poor weight gain and low feed efficiency in infected chickens. There are a large number of reported serotypes/genotypes, which makes the control of the disease more difficult through vaccination. However, there are only a few amino acid differences in the S1 protein of vaccine and wild type strains which are responsible for protection.

The purpose of this study is to compare IBV variants isolated from commercial chicken flocks in Iran with currently used vaccine strains. METHODES: The partial S1 gene of the spike protein, covering a hypervariable and constant regions, was amplified and sequenced using conventional RT-PCR.

Phylogenetic analysis of amino acid sequences revealed that eight of total nine isolates were divergence at least 21.8% from vaccinal Massachusetts serotypes, and six of nine isolates were divergence at least 22.7% from 4/91, and none of the nine isolates were similar to Dutch-type, D274,vaccine serotypes.

These findings are essential for continuous surveillance disease control strategies and monitoring of variants, and thus emphasize on the importance of improving the vaccination program in Iran.