Avian influenza in cats

Last updated

Cats with avian influenza exhibit symptoms that can result in death. They are one of the few species that can get avian influenza. The viruses cats may get include H5N1 or H7N2 [1] , which are subtypes of avian influenza. In order to get the virus, cats need to be in contact with waterfowl, poultry, or uncooked poultry that are infected. [2] Two of the main organs that the virus affects are the lungs and liver. [3]

Contents

History

The H5N1 virus has been found in China, Thailand, Vietnam, Indonesia, Iraq, Austria, Germany, and Poland. Besides being found in domestic cats, the virus has infected a variety of wild cats such as the Asiatic golden cat, the clouded leopard, tigers, and leopards. [4]

H5N1 was first discovered in domestic and wild cats in Asia, [5] specifically in 2003 in the Thai zoo where two tigers and two leopards died. In 2004, the Thai zoo had 147 tigers that died or were euthanized. [6] This was then followed by an outbreak in Germany in 2006, where three stray cats were found to be either dying or dead during the peak time of the virus outbreak. [7] Currently, as of June 2023, there is an ongoing outbreak in Poland with at least 9 confirmed cases and multiple deaths. [8]

Because the virus infects the lungs of cats, it is one of the preferred model animals to study the effects of H5N1 in humans. [4]

Virus

The most common way a cat can obtain H5N1 is by consuming an infected bird. This has been studied in the 2006 and 2007 cases in Germany and Austria where the strains between the cat and the infected birds were not different between the species. [7] A cat is able to then transfer the virus via the respiratory tract and the digestive tract to other cats. However, studies suggest that a cat cannot transfer the virus to a dog, and vice versa, while sharing a food bowl. [4] Though there is no concrete evidence, there is a potential link between the transfer of the virus between poultry, wild birds, and humans. [9]

Once the cat is infected, after an incubation period of 2 to 3 days, [5] the virus can be found in the respiratory tissues, attached to the type II pneumocytes and alveolar macrophages, [4] as well as the intestinal tissues. There have also been some cases where the virus has been found in the brain and other systems in the body. [10]

As of right now the H5N1 virus has not adapted to transfer in between mammals, but there is a fear that this can occur. [3]

Studies done with cats

One epidemiological study that was performed in Germany and Austria on 171 cats found that less than 1.8% of this population had H5N1. In this same sample population of cats, less than 2.6% had antibodies to H5N1. Even though Germany and Austria are among the countries that have had naturally occurring cases, this study shows that very few cats have contracted the disease. [11]

There have also been studies looking at the T cells, specifically CD4 and CD8, in the cat after viral infection. Though the mechanism is not fully known, there seems to be an inverse relationship with the amount of T cells present and the amount of infected cells. [12]

Another study to test whether the ALVAC recombinant canarypox virus could prime the immune system in cats was performed. This vaccine has the same hemagglutinin as the H5N1 virus, and therefore worked on preventing death from two different strains of the virus, HPAIV A/Vietnam/1194/2004 and HPAIV A/Indonesia/05/2005. However, some of the cats that were vaccinated did exhibit hyperthermia and weight loss, and all of the cats did have some disease change (assuming lesions) in their lungs. All of the cats, except one, still excreted the virus even after being vaccinated. [13]

Symptoms

A cat that is infected with a high dose of the virus can show signs of fever, lethargy, and dyspnea. [10] There have even been recorded cases where a cat has neurological symptoms such as circling or ataxia. [2] In a case in February 2004, a 2-year-old male cat was panting and convulsing on top of having a fever two days prior to death. This cat also had lesions that were identified as renal congestion, pulmonary congestion, edema, and pneumonia. Upon inspection, the cat also had cerebral congestion, conjunctivitis, and hemorrhaging in the serosae of the intestines. [14]

However, a cat that is infected with a low dose of the virus may not necessarily show symptoms. Though they may be asymptomatic, they can still transfer small amounts of the virus. [4]

Treatment and prevention

Cats can be protected from H5N1 if they are given a vaccination, as mentioned above. However, it was also found that cats can still shed some of the virus but in low numbers. [4]

If a cat is exhibiting symptoms, they should be put into isolation and kept indoors. Then they should be taken to a vet to get tested for the presence of H5N1. If there is a possibility that the cat has Avian Influenza, then there should be extra care when handling the cat. [2] Some of the precautions include avoiding all direct contact with the cat by wearing gloves, masks, and goggles. Whatever surfaces the cat comes in contact with should be disinfected with standard household cleaners. [5]

Researchers have given tigers an antiviral treatment of Oseltamivir with a dose of 75 mg/60 kg two times a day. The specific dosage was extrapolated from human data, but there hasn't been any data to suggest protection. As with many antiviral treatments, the dosage depends on the species. [5]

Related Research Articles

<i>Influenza A virus</i> Species of virus

Influenza A virus (IAV) is a pathogen that causes the flu in birds and some mammals, including humans. It is an RNA virus whose subtypes have been isolated from wild birds. Occasionally, it is transmitted from wild to domestic birds, and this may cause severe disease, outbreaks, or human influenza pandemics.

<span class="mw-page-title-main">Avian influenza</span> Influenza caused by viruses adapted to birds

Avian influenza, also known as avian flu or bird flu, is a disease caused by the influenza A virus, which can infect both birds and people. It is similar to other types of animal flu in that it is caused by a virus strain that has adapted to a specific host. The type with the greatest risk is highly pathogenic avian influenza (HPAI).

<i>Feline immunodeficiency virus</i> Species of virus

Feline immunodeficiency virus (FIV) is a Lentivirus that affects cats worldwide, with 2.5% to 4.4% of felines being infected.

<span class="mw-page-title-main">Influenza A virus subtype H5N1</span> Subtype of influenza A virus

Influenza A virus subtype H5N1 (A/H5N1) is a subtype of the influenza A virus, which causes influenza (flu), predominantly in birds. It is enzootic in many bird populations, and also panzootic. A/H5N1 virus can also infect mammals which have been exposed to infected birds; in these cases symptoms are frequently severe or fatal.

<span class="mw-page-title-main">Canine parvovirus</span> Contagious virus mainly affecting dogs

Canine parvovirus is a contagious virus mainly affecting dogs and wolves. CPV is highly contagious and spreads from dog to dog by direct or indirect contact with their feces. Vaccines can prevent this infection, but mortality can reach 91% in untreated cases. Often, treatment involves veterinary hospitalization, and Canine parvovirus infects other mammals, including foxes, wolves, cats, and skunks. Felines (cats) are also susceptible to panleukopenia, a different strain of parvovirus.

<span class="mw-page-title-main">Influenza pandemic</span> Pandemic involving influenza

An influenza pandemic is an epidemic of an influenza virus that spreads across a large region and infects a large proportion of the population. There have been six major influenza epidemics in the last 140 years, with the 1918 flu pandemic being the most severe; this is estimated to have been responsible for the deaths of 50–100 million people. The 2009 swine flu pandemic resulted in under 300,000 deaths and is considered relatively mild. These pandemics occur irregularly.

<span class="mw-page-title-main">Canine influenza</span>

Canine influenza is influenza occurring in canine animals. Canine influenza is caused by varieties of influenzavirus A, such as equine influenza virus H3N8, which was discovered to cause disease in canines in 2004. Because of the lack of previous exposure to this virus, dogs have no natural immunity to it. Therefore, the disease is rapidly transmitted between individual dogs. Canine influenza may be endemic in some regional dog populations of the United States. It is a disease with a high morbidity but a low incidence of death.

<span class="mw-page-title-main">Global spread of H5N1</span> Spread of bird flu

The global spread of H5N1 influenza in birds is considered a significant pandemic threat. While other H5N1 influenza strains are known, they are significantly different on a genetic level from a recent, highly pathogenic, emergent strain of H5N1, which was able to achieve hitherto unprecedented global spread in 2008. The H5N1 strain is a fast-mutating, highly pathogenic avian influenza virus (HPAI) found in multiple bird species. It is both epizootic and panzootic. Unless otherwise indicated, "H5N1" in this timeline refers to the recent highly pathogenic strain of H5N1.

<span class="mw-page-title-main">Transmission and infection of H5N1</span> Spread of an influenza virus

Transmission and infection of H5N1 from infected avian sources to humans has been a concern since the first documented case of human infection in 1997, due to the global spread of H5N1 that constitutes a pandemic threat.

<span class="mw-page-title-main">Influenza A virus subtype H5N2</span> Virus subtype

H5 N2 is a subtype of the species Influenzavirus A. The subtype infects a wide variety of birds, including chickens, ducks, turkeys, falcons, and ostriches. Affected birds usually do not appear ill, and the disease is often mild as avian influenza viral subtypes go. Some variants of the subtype are much more pathogenic than others, and outbreaks of "high-path" H5N2 result in the culling of thousands of birds in poultry farms from time to time. It appears that people who work with birds can be infected by the virus, but suffer hardly any noticeable health effects. Even people exposed to the highly pathogenic H5N2 variety that killed ostrich chicks in South Africa only seem to have developed conjunctivitis, or a perhaps a mild respiratory illness. There is no evidence of human-to-human spread of H5N2. On November 12, 2005 it was reported that a falcon was found to have H5N2.

<span class="mw-page-title-main">H5N1 genetic structure</span>

H5N1 genetic structure is the molecular structure of the H5N1 virus's RNA.

<span class="mw-page-title-main">Spanish flu research</span> Scientific research of the 1918 influenza pandemic

Spanish flu research concerns studies regarding the causes and characteristics of the Spanish flu, a variety of influenza that in 1918 was responsible for the worst influenza pandemic in modern history. Many theories about the origins and progress of the Spanish flu persisted in the literature, but it was not until 2005, when various samples of lung tissue were recovered from American World War I soldiers and from an Inupiat woman buried in permafrost in a mass grave in Brevig Mission, Alaska, that significant genetic research was made possible.

<span class="mw-page-title-main">NS1 influenza protein</span>

The NS1 influenza protein (NS1) is a viral nonstructural protein encoded by the NS gene segments of type A, B and C influenza viruses. Also encoded by this segment is the nuclear export protein (NEP), formally referred to as NS2 protein, which mediates the export of influenza virus ribonucleoprotein (RNP) complexes from the nucleus, where they are assembled.

<span class="mw-page-title-main">Fujian flu</span> Strains of influenza

Fujian flu refers to flu caused by either a Fujian human flu strain of the H3N2 subtype of the Influenza A virus or a Fujian bird flu strain of the H5N1 subtype of the Influenza A virus. These strains are named after Fujian, a coastal province in Southeast China.

<span class="mw-page-title-main">Human mortality from H5N1</span>

Human mortality from H5N1 or the human fatality ratio from H5N1 or the case-fatality rate of H5N1 is the ratio of the number of confirmed human deaths resulting from confirmed cases of transmission and infection of H5N1 to the number of those confirmed cases. For example, if there are 100 confirmed cases of humans infected with H5N1 and 50 die, then there is a 50% human fatality ratio. H5N1 flu is a concern due to the global spread of H5N1 that constitutes a pandemic threat. The majority of H5N1 flu cases have been reported in southeast and east Asia. The case-fatality rate is central to pandemic planning. Estimates of case-fatality (CF) rates for past influenza pandemics have ranged from to 2-3% for the 1918 pandemic to about 0.6% for the 1957 pandemic to 0.2% for the 1968 pandemic. As of 2008, the official World Health Organization estimate for the case-fatality rate for the outbreak of H5N1 avian influenza was approximately 60%. Public health officials in Ontario, Canada argue that the true case-fatality rate could be lower, pointing to studies suggesting it could be 14-33%, and warned that it was unlikely to be as low as the 0.1–0.4% rate that was built into many pandemic plans.

<span class="mw-page-title-main">Influenza</span> Infectious disease

Influenza, commonly known as "the flu" or just "flu", is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms begin one to four days after exposure to the virus and last for about two to eight days. Diarrhea and vomiting can occur, particularly in children. Influenza may progress to pneumonia from the virus or a subsequent bacterial infection. Other complications include acute respiratory distress syndrome, meningitis, encephalitis, and worsening of pre-existing health problems such as asthma and cardiovascular disease.

<span class="mw-page-title-main">Pandemic H1N1/09 virus</span> Virus responsible for the 2009 swine flu pandemic

The pandemic H1N1/09 virus is a swine origin influenza A virus subtype H1N1 strain that was responsible for the 2009 swine flu pandemic. This strain is often called swine flu by the public media due to the prevailing belief that it originated in pigs. The virus is believed to have originated around September 2008 in central Mexico.

<span class="mw-page-title-main">H5N1 vaccine</span> Vaccine designed to provide immunity against H5N1 influenza

A H5N1 vaccine is an influenza vaccine intended to provide immunization to influenza A virus subtype H5N1.

This is a timeline of influenza, briefly describing major events such as outbreaks, epidemics, pandemics, discoveries and developments of vaccines. In addition to specific year/period-related events, there is the seasonal flu that kills between 250,000 and 500,000 people every year and has claimed between 340 million and 1 billion human lives throughout history.

Since 2020, global outbreaks of avian influenza subtype H5N1 have been occuring, with cases reported from every continent as of April 2024 except for Australia. In late 2023, H5N1 was discovered in the Antarctic for the first time, raising fears of imminent spread throughout the region, potentially leading to a "catastrophic breeding failure" among animals that had not previously been exposed to avian influenza viruses. The main virus involved in the global outbreak is classified as H5N1 clade 2.3.4.4b, however genetic diversification with other clades such as 2.3.2.1c has seen the virus evolve in ability to cause significant outbreaks in a broader range of species including mammals.

References

  1. ↑ Lee, Christopher T (28 July 2017). "Outbreak of Influenza A(H7N2) Among Cats in an Animal Shelter With Cat-to-Human Transmission—New York City, 2016". academic.oup.com. Retrieved 2024-05-16.
  2. 1 2 3 Thiry, Etienne; Addie, Diane; Belák, Sándor; Boucraut-Baralon, Corine; Egberink, Herman; Frymus, Tadeusz; Gruffydd-Jones, Tim; Hartmann, Katrin; Hosie, Margaret J.; Lloret, Albert (1 July 2009). "H5N1 avian influenza in cats. ABCD guidelines on prevention and management". Journal of Feline Medicine & Surgery. 11 (7): 615–618. doi:10.1016/j.jfms.2009.05.011. PMC   7128855 . PMID   19481042.
  3. 1 2 Marschall, J; Hartmann, K (1 August 2008). "Avian influenza A H5N1 infections in cats". Journal of Feline Medicine & Surgery. 10 (4): 359–365. doi:10.1016/j.jfms.2008.03.005. PMID   18619884. S2CID   29347001.
  4. 1 2 3 4 5 6 Harder TC, Vahlenkamp TW (March 2010). "Influenza virus infections in dogs and cats". Vet. Immunol. Immunopathol. 134 (1–2): 54–60. doi:10.1016/j.vetimm.2009.10.009. PMID   19896216.
  5. 1 2 3 4 Philippa J, Baas C, Beyer W, et al. (May 2007). "Vaccination against highly pathogenic avian influenza H5N1 virus in zoos using an adjuvanted inactivated H5N2 vaccine". Vaccine. 25 (19): 3800–8. doi:10.1016/j.vaccine.2007.01.121. PMID   17403559.
  6. ↑ Yee KS, Carpenter TE, Cardona CJ (July 2009). "Epidemiology of H5N1 avian influenza". Comp. Immunol. Microbiol. Infect. Dis. 32 (4): 325–40. doi:10.1016/j.cimid.2008.01.005. PMID   18448168.
  7. 1 2 Starick, E.; Beer, M.; Hoffmann, B.; Staubach, C.; Werner, O.; Globig, A.; Strebelow, G.; Grund, C.; Durban, M.; Conraths, F.J.; Mettenleiter, T.; Harder, T. (1 April 2008). "Phylogenetic analyses of highly pathogenic avian influenza virus isolates from Germany in 2006 and 2007 suggest at least three separate introductions of H5N1 virus" (PDF). Veterinary Microbiology. 128 (3–4): 243–252. doi:10.1016/j.vetmic.2007.10.012. PMID   18031958.
  8. ↑ Schnirring, Lisa. "Polish officials probe H5N1 avian flu link to cat deaths". Center for Infectious Disease Research and Policy. University of Minnesota. Retrieved 28 June 2023.
  9. ↑ Kalthoff D, Globig A, Beer M (January 2010). "(Highly pathogenic) avian influenza as a zoonotic agent". Vet. Microbiol. 140 (3–4): 237–45. doi:10.1016/j.vetmic.2009.08.022. PMID   19782482.
  10. 1 2 Belser JA, Tumpey TM (February 2013). "H5N1 pathogenesis studies in mammalian models". Virus Res. 178 (1): 168–85. doi:10.1016/j.virusres.2013.02.003. PMC   5858902 . PMID   23458998.
  11. ↑ Marschall, J; Schulz, B; Harderprivdoz, T; Vahlenkampprivdoz, T; Huebner, J; Huisinga, E; Hartmann, K (1 August 2008). "Prevalence of influenza A H5N1 virus in cats from areas with occurrence of highly pathogenic avian influenza in birds". Journal of Feline Medicine & Surgery. 10 (4): 355–358. doi: 10.1016/j.jfms.2008.03.007 . PMID   18640861. S2CID   6326717.
  12. ↑ Giese, Matthias; Harder, Timm C.; Teifke, Jens P.; Mettenleiter, Thomas C.; Vahlenkamp, Thomas W. (1 March 2009). "The role of T cells in avian influenza H5N1 infected cats". Veterinary Immunology and Immunopathology. 128 (1–3): 343. doi:10.1016/j.vetimm.2008.10.282.
  13. ↑ Stittelaar, Koert J.; Lacombe, Valérie; van Lavieren, Rob; van Amerongen, Geert; Simon, James; Cozette, Valérie; Swayne, David E.; Poulet, Hervé; Osterhaus, Albert D.M.E. (1 July 2010). "Cross-clade immunity in cats vaccinated with a canarypox-vectored avian influenza vaccine". Vaccine. 28 (31): 4970–4976. doi:10.1016/j.vaccine.2010.05.028. PMID   20566392.
  14. ↑ Cardona CJ, Xing Z, Sandrock CE, Davis CE (July 2009). "Avian influenza in birds and mammals". Comp. Immunol. Microbiol. Infect. Dis. 32 (4): 255–73. doi:10.1016/j.cimid.2008.01.001. PMID   18485480.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.