Comparison of Human-Like H1 (-Cluster) Influenza A Viruses in the Swine Host

Influenza A viruses cause acute respiratory disease in swine. Viruses with H1 hemagglutinin genes from the human seasonal lineage (-cluster) have been isolated from North American swine since 2003. The objective of this work was to study the pathogenesis and transmission of -cluster H1 influenza viruses in swine, comparing three isolates from different phylogenetic subclusters, geographic locations, and years of isolation. Two isolates from the 2 subcluster, A/sw/MN/07002083/07 H1N1 (MN07) and A/sw/IL/00685/05 H1N1 (IL05), and A/sw/TX/01976/08 H1N2 (TX08) from the 1 sub-cluster were evaluated. All isolates caused disease and were transmitted to contact pigs. Respiratory disease was apparent in pigs infected with MN07 and IL05 viruses; however, clinical signs and lung lesions were reduced in severity as compared to TX08. On day 5 following infection MN07-infected pigs had lower virus titers than the TX08 pigs, suggesting that although this H1N1 was successfully transmitted, it may not replicate as efficiently in the upper or lower respiratory tract. MN07 and IL05 H1N1 induced higher serum antibody titers than TX08. Greater serological cross-reactivity was observed for viruses from the same HA phylogenetic sub-cluster; however, antigenic differences between the sub-clusters may have implications for disease control strategies for pigs.

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PRESENCE OF RESPIRATORY VIRUSES IN EQUINES IN BRAZIL

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652014000300002 ◽

2014 ◽

Vol 56 (3) ◽

pp. 191-195

Author(s):

Dalva Assunção Portari Mancini ◽

Aparecida Santo Pietro Pereira ◽

Rita Maria Zucatelli Mendonça ◽

Adelia Hiroko Nagamori Kawamoto ◽

Rosely Cabette Barbosa Alves ◽

...

Keyword(s):

Influenza A ◽

Respiratory Viruses ◽

Influenza Viruses ◽

Influenza A Viruses ◽

Equine Influenza ◽

Hemagglutination Inhibition Test ◽

Parainfluenza Viruses ◽

Significant Difference ◽

Antibody Titers ◽

The Difference

Equines are susceptible to respiratory viruses such as influenza and parainfluenza. Respiratory diseases have adversely impacted economies all over the world. This study was intended to determine the presence of influenza and parainfluenza viruses in unvaccinated horses from some regions of the state of São Paulo, Brazil. Blood serum collected from 72 equines of different towns in this state was tested by hemagglutination inhibition test to detect antibodies for both viruses using the corresponding antigens. About 98.6% (71) and 97.2% (70) of the equines responded with antibody protective titers (≥ 80 HIU/25µL) H7N7 and H3N8 subtypes of influenza A viruses, respectively. All horses (72) also responded with protective titers (≥ 80) HIU/25µL against the parainfluenza virus. The difference between mean antibody titers to H7N7 and H3N8 subtypes of influenza A viruses was not statistically significant (p > 0.05). The mean titers for influenza and parainfluenza viruses, on the other hand, showed a statistically significant difference (p < 0.001). These results indicate a better antibody response from equines to parainfluenza 3 virus than to the equine influenza viruses. No statistically significant differences in the responses against H7N7 and H3N8 subtypes of influenza A and parainfluenza 3 viruses were observed according to the gender (female, male) or the age (≤ 2 to 20 years-old) groups. This study provides evidence of the concomitant presence of two subtypes of the equine influenza A (H7N7 and H3N8) viruses and the parainfluenza 3 virus in equines in Brazil. Thus, it is advisable to vaccinate equines against these respiratory viruses.

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Efficacy of Heterologous Prime-Boost Vaccination with H3N2 Influenza Viruses in Pre-Immune Individuals: Studies in the Pig Model

Viruses ◽

10.3390/v12090968 ◽

2020 ◽

Vol 12 (9) ◽

pp. 968

Author(s):

Sharon Chepkwony ◽

Anna Parys ◽

Elien Vandoorn ◽

Koen Chiers ◽

Kristien Van Reeth

Keyword(s):

Lymph Nodes ◽

Influenza A ◽

Serum Antibody ◽

Swine Influenza ◽

Cross Reactivity ◽

Influenza Viruses ◽

Antibody Responses ◽

Pig Model ◽

Boost Vaccination ◽

H3n2 Influenza

In a previous study in influenza-naïve pigs, heterologous prime-boost vaccination with monovalent, adjuvanted whole inactivated vaccines (WIV) based on the European swine influenza A virus (SwIAV) strain, A/swine/Gent/172/2008 (G08), followed by the US SwIAV strain, A/swine/Pennsylvania/A01076777/2010 (PA10), was shown to induce broadly cross-reactive hemagglutination inhibition (HI) antibodies against 12 out of 15 antigenically distinct H3N2 influenza strains. Here, we used the pig model to examine the efficacy of that particular heterologous prime-boost vaccination regimen, in individuals with pre-existing infection-immunity. Pigs were first inoculated intranasally with the human H3N2 strain, A/Nanchang/933/1995. Seven weeks later, they were vaccinated intramuscularly with G08 followed by PA10 or vice versa. We examined serum antibody responses against the hemagglutinin and neuraminidase, and antibody-secreting cell (ASC) responses in peripheral blood, draining lymph nodes, and nasal mucosa (NMC), in ELISPOT assays. Vaccination induced up to 10-fold higher HI antibody titers than in naïve pigs, with broader cross-reactivity, and protection against challenge with an antigenically distant H3N2 strain. It also boosted ASC responses in lymph nodes and NMC. Our results show that intramuscular administration of WIV can lead to enhanced antibody responses and cross-reactivity in pre-immune subjects, and recall of ASC responses in lymph nodes and NMC.

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Kallikrein-Related Peptidase 5 Contributes to H3N2 Influenza Virus Infection in Human Lungs

Journal of Virology ◽

10.1128/jvi.00421-17 ◽

2017 ◽

Vol 91 (16) ◽

Cited By ~ 7

Author(s):

Mélia Magnen ◽

Fabien Gueugnon ◽

Antoine Guillon ◽

Thomas Baranek ◽

Virginie C. Thibault ◽

...

Keyword(s):

Influenza Virus ◽

Respiratory Tract ◽

Serine Proteases ◽

Lower Respiratory Tract ◽

Influenza A ◽

Seasonal Influenza ◽

Influenza Viruses ◽

H3n2 Virus ◽

Influenza A Viruses

ABSTRACT Hemagglutinin (HA) of influenza virus must be activated by proteolysis before the virus can become infectious. Previous studies indicated that HA cleavage is driven by membrane-bound or extracellular serine proteases in the respiratory tract. However, there is still uncertainty as to which proteases are critical for activating HAs of seasonal influenza A viruses (IAVs) in humans. This study focuses on human KLK1 and KLK5, 2 of the 15 serine proteases known as the kallikrein-related peptidases (KLKs). We find that their mRNA expression in primary human bronchial cells is stimulated by IAV infection. Both enzymes cleaved recombinant HA from several strains of the H1 and/or H3 virus subtype in vitro, but only KLK5 promoted the infectivity of A/Puerto Rico/8/34 (H1N1) and A/Scotland/20/74 (H3N2) virions in MDCK cells. We assessed the ability of treated viruses to initiate influenza in mice. The nasal instillation of only the KLK5-treated virus resulted in weight loss and lethal outcomes. The secretion of this protease in the human lower respiratory tract is enhanced during influenza. Moreover, we show that pretreatment of airway secretions with a KLK5-selective inhibitor significantly reduced the activation of influenza A/Scotland/20/74 virions, providing further evidence of its importance. Differently, increased KLK1 secretion appeared to be associated with the recruitment of inflammatory cells in human airways regardless of the origin of inflammation. Thus, our findings point to the involvement of KLK5 in the proteolytic activation and spread of seasonal influenza viruses in humans. IMPORTANCE Influenza A viruses (IAVs) cause acute infection of the respiratory tract that affects millions of people during seasonal outbreaks every year. Cleavage of the hemagglutinin precursor by host proteases is a critical step in the life cycle of these viruses. Consequently, host proteases that activate HA can be considered promising targets for the development of new antivirals. However, the specific proteases that activate seasonal influenza viruses, especially H3N2 viruses, in the human respiratory tract have remain undefined despite many years of work. Here we demonstrate that the secreted, extracellular protease KLK5 (kallikrein-related peptidase 5) is efficient in promoting the infectivity of H3N2 IAV in vitro and in vivo. Furthermore, we found that its secretion was selectively enhanced in the human lower respiratory tract during a seasonal outbreak dominated by an H3N2 virus. Collectively, our data support the clinical relevance of this protease in human influenza pathogenesis.

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Swine influenza: Newer data on diagnosis, interpretation of the results, and control

Medycyna Weterynaryjna ◽

10.21521/mw.6506 ◽

2021 ◽

Vol 77 (02) ◽

pp. 6506-2021

Author(s):

ZYGMUNT PEJSAK ◽

KAZIMIERZ TARASIUK

Keyword(s):

Influenza A ◽

Bacterial Infections ◽

Clinical Signs ◽

Swine Influenza ◽

Water System ◽

Influenza Viruses ◽

Upper Respiratory Tract ◽

Influenza A Viruses ◽

Serological Tests ◽

Specific Antibodies

Influenza viruses are among the major causes of acute respiratory disease outbreaks in pigs. In most cases, infections are subclinical. Until 2009, three subtypes of IAV-S circulated in the pig population in Europe, with some geographical restrictions regarding their prevalence: avian-like (av) H1N1, reassortant (r) H3N2, and human (hu) H1N2. Viruses of the H1N1av lineage appeared to be responsible for the majority of swine infections in Europe. In 2009, a fourth subtype entered the pig population: the human pandemic H1N1 2009 influenza A virus (H1N1pdm). Due to the expression of receptors with α-2-6 or α-2-3-linked terminal sialic acids in the porcine upper respiratory tract, swine appear to be susceptible to influenza A viruses of both avian and human origin. A clinical diagnosis of swine influenza is not easy, since there are no observable pathognomonic clinical signs, and the disease must be distinguished from a variety of other respiratory conditions in pigs. A final diagnosis can be made by the following methods: detection of viral proteins or nucleic acid, isolation of virus, or demonstration of virus-specific antibodies. IAV-S is most likely to be found in nasal and pharyngeal secretions during the fever period of illness. Serological tests are used to demonstrate the presence of influenza-specific antibodies. Serology is the most useful technique to determine the immune status of the herd, to assess the levels of maternally derived antibodies in young piglets and their profile, as well as post-vaccination antibody titers, and to perform pre-movement testing of pigs. The interpretation of serological data is often complex and may be further confounded by concurrent circulation of different virus subtypes and gene lineages. In control of IAV-S, vaccination appears to be the primary tool for preventing influenza. The efficacy of vaccination may be various and is correlated with homology between vaccine and field IAV-S strains. There is no treatment available for IAV-S. The administration of aspirin via the water system or of paracetamol in feed may play a role as a support therapy. To avoid subsequent bacterial infections, treatment with an antibiotic is essential.

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Three Types of Broadly Reacting Antibodies against Influenza B Viruses Induced by Vaccination with Seasonal Influenza Viruses

Journal of Immunology Research ◽

10.1155/2018/7251793 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15 ◽

Cited By ~ 6

Author(s):

Daisuke Hirano ◽

Nobuko Ohshima ◽

Ritsuko Kubota-Koketsu ◽

Ayami Yamasaki ◽

Gene Kurosawa ◽

...

Keyword(s):

Influenza A ◽

Seasonal Influenza ◽

Mononuclear Cells ◽

Cross Reactivity ◽

Influenza Viruses ◽

Influenza B ◽

Influenza A Viruses ◽

Phage Display Technology ◽

Display Technology ◽

2009 H1n1

We analyzed the antibody (Ab) repertoire against influenza B viruses induced by vaccination with seasonal influenza viruses in one individual who had never been vaccinated until 2009. The vaccine used in this study comprised B/Massachusetts/2/2012 (Yamagata lineage), A/Texas/50/2012 (H3N2), and A/California/7/2009 (H1N1). One month after the subject received two vaccinations, blood (200 ml) was obtained and peripheral mononuclear cells were prepared, and a large Ab library was constructed using phage display technology. The library was screened with HA-enriched fraction of B/Massachusetts/2/2012 and B/Brisbane/60/2008 (Victoria lineage) virus, and a total of 26 Abs that potentially bound to hemagglutinin (HA) molecules were isolated. Their binding activities to six influenza B viruses, three of Yamagata lineage and three of Victoria lineage, and two influenza A viruses, H1N1 and H3N2, were examined. The Abs showed cross-reactivity at three different levels. The first type bound to all Yamagata lineage viruses. The second type bound to both Yamagata and Victoria lineage viruses. The third type bound to both influenza A and B viruses. These results indicate that common epitopes exist on HA molecules of influenza virus at various levels, and humans have capability to produce Abs that bind to such common epitopes.

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Isolation and Characterization of a Distinct Influenza A Virus from Egyptian Bats

Journal of Virology ◽

10.1128/jvi.01059-18 ◽

2018 ◽

Vol 93 (2) ◽

Cited By ~ 8

Author(s):

Ahmed Kandeil ◽

Mokhtar R. Gomaa ◽

Mahmoud M. Shehata ◽

Ahmed N. El Taweel ◽

Sara H. Mahmoud ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Mdck Cells ◽

Genomic Analysis ◽

Cross Reactivity ◽

Influenza Viruses ◽

Avian Host ◽

Influenza A Viruses ◽

Species Barrier ◽

Isolation And Characterization

ABSTRACT Recently, two genetically distinct influenza viruses were detected in bats in Guatemala and Peru. We conducted influenza A virus surveillance among four bat species in Egypt. Out of 1,202 swab specimens, 105 were positive by real-time PCR. A virus was successfully isolated in eggs and propagated in MDCK cells in the presence of N-tosyl-l-phenylalanine chloromethyl ketone-treated trypsin. Genomic analysis revealed that the virus was phylogenetically distinct from all other influenza A viruses. Analysis of the hemagglutinin gene suggested a common ancestry with other H9 viruses, and the virus showed a low level of cross-reactivity with serum raised against H9N2 viruses. Bats were seropositive for the isolated viruses. The virus replicated in the lungs of experimentally infected mice. While it is genetically distinct, this virus shares several avian influenza virus characteristics suggesting a more recent avian host origin. IMPORTANCE Through surveillance, we isolated and characterized an influenza A virus from Egyptian fruit bats. This virus had an affinity to avian-like receptors but was also able to infect mice. Our findings indicate that bats may harbor a diversity of influenza A viruses. Such viruses may have the potential to cross the species barrier to infect other species, including domestic birds, mammals, and, possibly, humans.

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Genetic and pathogenic characteristics of H1 avian and swine influenza A viruses

Journal of General Virology ◽

10.1099/vir.0.065524-0 ◽

2014 ◽

Vol 95 (10) ◽

pp. 2118-2126 ◽

Cited By ~ 5

Author(s):

Hyun-Mi Kang ◽

Eun-Kyoung Lee ◽

Byung-Min Song ◽

Jipseol Jeong ◽

Hye-Ryoung Kim ◽

...

Keyword(s):

Influenza A ◽

Wild Bird ◽

Phylogenetic Analyses ◽

Clinical Signs ◽

Influenza Viruses ◽

Interspecies Transmission ◽

Post Inoculation ◽

Domestic Duck ◽

Influenza A Viruses ◽

Domestic Ducks

This study examined the potential for cross-species transmission of influenza viruses by comparing the genetic and pathogenic characteristics of H1 avian influenza viruses (AIVs) with different host origins in Korea. Antigenic and phylogenetic analyses of H1 AIVs circulating in Korea provided evidence of genetic similarity between viruses that infect domestic ducks and those that infect wild birds, although there was no relationship between avian and swine viruses. However, there were some relationships between swine and human viral genes. The replication and pathogenicity of the H1 viruses was assessed in chickens, domestic ducks and mice. Viral shedding in chickens was relatively high. Virus was recovered from both oropharyngeal and cloacal swabs up to 5–10 days post-inoculation. The titres of domestic duck viruses in chickens were much higher than those of wild-bird viruses. Both domestic duck and wild-bird viruses replicated poorly in domestic ducks. None of the swine viruses replicated in chickens or domestic ducks; however, six viruses showed relatively high titres in mice, regardless of host origin, and induced clinical signs such as ruffled fur, squatting and weight loss. Thus, although the phylogenetic and antigenic analyses showed no evidence of interspecies transmission between birds and swine, the results suggest that Korean H1 viruses have the potential to cause disease in mammals. Therefore, we should intensify continuous monitoring of avian H1 viruses in mammals and seek to prevent interspecies transmission.

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Severe cases of seasonal influenza in Russia in 2017-2018

Journal of microbiology epidemiology immunobiology ◽

10.36233/0372-9311-2019-4-58-64 ◽

2019 ◽

pp. 58-64 ◽

Cited By ~ 1

Author(s):

S. V. Svyatchenko ◽

A. G. Durymanov ◽

N. P. Kolosova ◽

A. S. Gudymo ◽

N. I. Goncharova ◽

...

Keyword(s):

Influenza A ◽

Seasonal Influenza ◽

Effective Means ◽

Herd Immunity ◽

Clinical Signs ◽

Neuraminidase Inhibitor ◽

Influenza Viruses ◽

Epidemic Season ◽

Antibody Titers

Aim.Evaluation of herd immunity prior to the 2017-2018 influenza season, and characterization of influenza viruses isolated from severe or fatal influenza cases and from influenza cases in people vaccinated in the fall of 2017.Materials and methods.Evaluation of herd immunity in hemagglutination inhibition assay. Isolation of influenza viruses. Antigenic and genetic analysis.Results.Prior to epidemic season 33-47% of blood sera samples collected on the territory of Russia showed presence of protective antibody titers against vaccine strains of influenza A, 24-30% of samples — against B/Victoria. During 2017-2018 epidemic season 87 influenza A and B viruses were isolated. A(H1N1)pdm09 strains belonged to clade 6B.1, B/Yamagata strains to clade 3, and B/Victoria strains to clade 1A; they were antigenically similar to corresponding vaccine strains. A(H3N2) viruses belonged to clade 3C.2a and were difficult to characterize antigenically. One strain of influenza virus А(H1N1pdm09) was resistant to oseltamivir and had H275Y amino acid substitution in neuraminidase. All other isolates were susceptible to neuraminidase inhibitors.Conclusion.Influenza vaccination with vaccine effective against current circulating strains and treatment with neuraminidase inhibitor drugs at first manifestation of clinical signs of influenza disease are effective means of population protection against influenza.

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Comparison of the Replication of Influenza A Viruses in Chinese Ring-Necked Pheasants and Chukar Partridges

Journal of Virology ◽

10.1128/jvi.80.5.2151-2161.2006 ◽

2006 ◽

Vol 80 (5) ◽

pp. 2151-2161 ◽

Cited By ~ 40

Author(s):

Jennifer Humberd ◽

Yi Guan ◽

Robert G. Webster

Keyword(s):

Avian Influenza ◽

Influenza A ◽

Genetic Interaction ◽

Neutralizing Antibody ◽

Neutralization Assay ◽

Influenza Viruses ◽

Intermediate Hosts ◽

Influenza A Viruses ◽

Antibody Titers ◽

Chukar Partridges

ABSTRACT We investigated the replication and transmission of avian influenza A viruses in two species thought to be intermediate hosts in the spread of influenza A viruses in live poultry markets: Chinese ring-necked pheasants and chukar partridges. All 15 hemagglutinin subtypes replicated in pheasants, and most subtypes transmitted to naïve contact pheasants, primarily via the fecal-oral route. Many viruses were shed from the gastrointestinal tract of experimentally inoculated pheasants for 14 days or longer. Virus was isolated from the cloacal swabs of one contact pheasant for an unprecedented 45 days. Chukar partridges were less susceptible to infection with avian influenza viruses. The viruses that replicated in chukar partridges were isolated for 7 days after experimental inoculation, predominantly from the respiratory tract. We detected high neutralizing antibody titers with correspondingly low levels of serum hemagglutination inhibition antibody titers in pheasants and chukar partridges when chicken red blood cells were used in serological analyses. When horse erythrocytes were used, antibody titers were comparable to those obtained by using the neutralization assay. More importantly, the results suggested that pheasants can serve as a reservoir of influenza virus. Because of their continuous asymptomatic infection and longer stay in the markets, pheasants are ideal “carriers” of influenza A viruses. Their continued presence in live markets contributes to the perpetuation and genetic interaction of influenza viruses there. On the basis of our findings, it does not make good sense to ban quail but not pheasants from the live markets.

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An evaluation of the InDevR FluChip-8G insight microarray assay in characterizing influenza a viruses

Tropical Diseases Travel Medicine and Vaccines ◽

10.1186/s40794-021-00133-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Emily S. Bailey ◽

Xinye Wang ◽

Mai-juan Ma ◽

Guo-lin Wang ◽

Gregory C. Gray

Keyword(s):

Influenza A ◽

Influenza Viruses ◽

Time Range ◽

Influenza B ◽

Influenza A Viruses ◽

Laboratory Methods ◽

Duke University ◽

Multiple Viral Strains ◽

Rapid Characterization

AbstractInfluenza viruses are an important cause of disease in both humans and animals, and their detection and characterization can take weeks. In this study, we sought to compare classical virology techniques with a new rapid microarray method for the detection and characterization of a very diverse, panel of animal, environmental, and human clinical or field specimens that were molecularly positive for influenza A alone (n = 111), influenza B alone (n = 3), both viruses (n = 13), or influenza negative (n = 2) viruses. All influenza virus positive samples in this study were first subtyped by traditional laboratory methods, and later evaluated using the FluChip-8G Insight Assay (InDevR Inc. Boulder, CO) in laboratories at Duke University (USA) or at Duke Kunshan University (China). The FluChip-8G Insight multiplexed assay agreed with classical virologic techniques 59 (54.1%) of 109 influenza A-positive, 3 (100%) of the 3 influenza B-positive, 0 (0%) of 10 both influenza A- and B-positive samples, 75% of 24 environmental samples including those positive for H1, H3, H7, H9, N1, and N9 strains, and 80% of 22 avian influenza samples. It had difficulty with avian N6 types and swine H3 and N2 influenza specimens. The FluChip-8G Insight assay performed well with most human, environmental, and animal samples, but had some difficulty with samples containing multiple viral strains and with specific animal influenza strains. As classical virology methods are often iterative and can take weeks, the FluChip-8G Insight Assay rapid results (time range 8 to 12 h) offers considerable time savings. As the FluChip-8G analysis algorithm is expected to improve over time with addition of new subtypes and sample matrices, the FluChip-8G Insight Assay has considerable promise for rapid characterization of novel influenza viruses affecting humans or animals.

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