Equine virology quiz

WIKIQUIZ

Questions reviewed by:

Janet Daly BSc PhD Lecturer in Comparative Virology

1

What does equine adenovirus cause in immunocompromised foals? Rhinitis and tracheobronchitis Rhinitis, peripheral oedema, bronchitis/bronchiolitis and conjunctivitis Necrotising bronchiolitis Pulmonary oedema A mild, transient bronchointerstitial pneumonia Please select an option Incorrect. Rhinitis and tracheobronchitis is seen in equine influenza caused by equine influenza virus (Orthomyxovirus). The severity of signs of equine influenza depends on the strain of the virus and the immune status of the animal. Often, acute tracheobronchitis with coughing and feverare seen, and may be accompanied by secondary bacterial infections. The correct answer is necrotising bronchiolitis, seen in immunocompromised foals (especially Arabian foals). WikiVet Article: Viruses Incorrect. Rhinitis, peripheral oedema, bronchitis/bronchiolitis and conjunctivitis are seen with equine viral arteritis (EVA) caused by equine arteritis virus. The correct answer is necrotising bronchiolitis which can be seen in immunocompromised foals (especially Arabian foals). WikiVet Article: Viruses Correct! Necrotising bronchiolitis caused by equine adenovirus can be seen in immunocompromised foals (especially Arabian foals). WikiVet Article: Viruses Incorrect. Pulmonary oedema is seen in African horse sickness caused by orbivirus, in the family reoviridae. There is respiratory distress or cardiovascular failure and rapid death due to the massive pulmonary oedema. The correct answer is necrotising bronchiolitis which can be seen in immunocompromised foals (especially Arabian foals). WikiVet Article: Viruses Incorrect. A mild, transient bronchointerstitial pneumonia is seen with equine rhinopneumonitis. The causative agent is equine herpesvirus type 1 and type 4 which produces primary viral lesions in nasal mucosa and lungs. Incorrect. The correct answer is necrotising bronchiolitis which can be seen in immunocompromised foals (especially Arabian foals). WikiVet Article: Viruses

2

Which notifiable equine virus remains latent in macrophages? Equine infectious anaemia Equine arteritis virus Equine encephalitis virus West Nile virus African horse sickness virus Please select an option Correct! Equine infectious anaemia is a notifiable disease caused by a retrovirus. The virus is transmitted in macrophages via vectors e.g. mosquitoes, although it can also be transferred via infected needles, semen and milk. Infected horses have a lifetime latent infection of macrophages with recurring bouts of virus when they become immunocompromised. WikiVet Article: equine infectious anaemia. Incorrect. Equine arteritis virus does not become latent in macrophages, although it can be persistently shed from the accessory sex glands of stallions after clinical infection. Equine infectious anaemia is a notifiable disease caused by a retrovirus. The virus is transmitted in macrophages via vectors e.g. mosquitoes, although it can also be transferred via infected needles, semen and milk. Infected horses have a lifetime latent infection of macrophages with recurring bouts of virus when they become immunocompromised. WikiVet Article: equine infectious anaemia. Incorrect. Equine encephalitis virus does not become latent in macrophages. Equine infectious anaemia is a notifiable disease caused by a retrovirus. The virus is transmitted in macrophages via vectors e.g. mosquitoes, although it can also be transferred via infected needles, semen and milk. Infected horses have a lifetime latent infection of macrophages with recurring bouts of virus when they become immunocompromised. WikiVet Article: equine infectious anaemia. Incorrect. West Nile virus does not become latent in macrophages. Equine infectious anaemia is a notifiable disease caused by a retrovirus. The virus is transmitted in macrophages via vectors e.g. mosquitoes, although it can also be transferred via infected needles, semen and milk. Infected horses have a lifetime latent infection of macrophages with recurring bouts of virus when they become immunocompromised. WikiVet Article: equine infectious anaemia. Incorrect. African horse sickness does not become latent in macrophages. Equine infectious anaemia is a notifiable disease caused by a retrovirus. The virus is transmitted in macrophages via vectors e.g. mosquitoes, although it can also be transferred via infected needles, semen and milk. Infected horses have a lifetime latent infection of macrophages with recurring bouts of virus when they become immunocompromised. WikiVet Article: equine infectious anaemia.

3

Which virus is most frequently associated with abortions in late gestation in the mare? Equine Infectious Anaemia virus (EIA) Equine Herpes Virus 1 (EHV1) African Horse Sickness virus Equine Arteritis Virus (EAV) Equine Influenza Virus Please select an option Incorrect. Equine Infectious Anaemia virus can cause abortion in pregnant mares, but this may occur at any time during the pregnancy, not necessarily towards the end of gestation. Remember EIA is notifiable in the UK. Equine Herpesvirus 1 is the most important viral cause of abortion in horses. 95% of abortions due to EHV1 are in the last trimester, when chorionic placentomes have created an end-artery system vulnerable to ischaemia. Abortion is not preceded by maternal illness. To control an EHV1 outbreak; pregnant mares should be isolated and there should be no movement for at least 1 month after the last abortion. There is a vaccine available which should be given every 6 months, but although it may reduce respiratory disease, it has not been shown to protect against abortion. . WikiVet Article: Equine Herpesvirus, Equine Infectious Anaemia virus. Correct! Equine Herpesvirus 1 is the most important viral cause of abortion in horses. 95% of abortions due to EHV1 are in the last trimester, when chorionic placentomes have created an end-artery system vulnerable to ischaemia. Abortion is not preceded by maternal illness. To control an EHV1 outbreak; pregnant mares should be isolated and there should be no movement for at least 1 month after the last abortion. There is a vaccine available which should be given every 6 months, but although it may reduce respiratory disease, it has not been shown to protect against abortion. . WikiVet Article: Equine Herpesvirus. Incorrect. African Horse Sickness virus is not usually associated with abortions although systemic illness and/or fever can cause the mare's system to secrete prostaglandins, which may cause abortion. Equine Herpesvirus 1 is the most important viral cause of abortion in horses. 95% of abortions due to EHV1 are in the last trimester, when chorionic placentomes have created an end-artery system vulnerable to ischaemia. Abortion is not preceded by maternal illness. To control an EHV1 outbreak; pregnant mares should be isolated and there should be no movement for at least 1 month after the last abortion. There is a vaccine available which should be given every 6 months, but although it may reduce respiratory disease, it has not been shown to protect against abortion. WikiVet Article: Equine Herpesvirus, African Horse Sickness virus. Incorrect. Abortions caused by EAV occur after 10-30 days in 50% of pregnant mareswhereas 95% of abortions due to Equine Herpesvirus 1 are in the last trimester, when chorionic placentomes have created an end-artery system vulnerable to ischaemia. Abortion is not preceded by maternal illness. EHV1 is the most important viral cause of abortion in horses. To control an EHV1 outbreak; pregnant mares should be isolated and there should be no movement for at least 1 month after the last abortion. There is a vaccine available which should be given every 6 months, but although it may reduce respiratory disease, it has not been shown to protect against abortion.WikiVet Article: Equine Herpesvirus, Equine Arteritis Virus. Incorrect. Equine Influenza virus is not usually associated with abortions in the mare, although systemic illness and/or fever can cause the mare's system to secrete prostaglandins, which may cause abortion. Equine Herpesvirus 1 is the most important viral cause of abortion in horses. 95% of abortions due to EHV1 are in the last trimester, when chorionic placentomes have created an end-artery system vulnerable to ischaemia. Abortion is not preceded by maternal illness. To control an EHV1 outbreak; pregnant mares should be isolated and there should be no movement for at least 1 month after the last abortion. There is a vaccine available which should be given every 6 months, but although it may reduce respiratory disease, it has not been shown to protect against abortion.WikiVet Article: Equine Herpesvirus, Equine Influenza virus.

4

Which notifiable virus can be shed for an extended period via the accessory sex glands of stallions, after clinical infection has subsided? West Nile virus Equine encephalitis virus African horse sickness virus Equine arteritis virus Equine infectious anaemia Please select an option Incorrect. West Nile virus is not shed in semen. The shedder stallion is a very important source of equine arteritis virus. During clinical infection, the virus can localise in the accessory sex glands and so can be shed in the stallion's semen for weeks, months or even years. The fertility of these stallions is unaffected and there are no clinical signs but they can transmit infection to mares during mating or if their semen is used for artificial insemination. WikiVet Article: equine arteritis virus. Link to webpage: Horserace Betting Levy Board Code of Practice for Equine Viral Arteritis. Incorrect. Equine encephalitis virus is not shed in semen. The shedder stallion is a very important source of equine arteritis virus. During clinical infection, the virus can localise in the accessory sex glands and so can be shed in the stallion's semen for weeks, months or even years. The fertility of these stallions is unaffected and there are no clinical signs but they can transmit infection to mares during mating or if their semen is used for artificial insemination. WikiVet Article: equine arteritis virus. Link to webpage: Horserace Betting Levy Board Code of Practice for Equine Viral Arteritis. Incorrect. African horse sickness virus is not shed in semen. The shedder stallion is a very important source of equine arteritis virus. During clinical infection, the virus can localise in the accessory sex glands and so can be shed in the stallion's semen for weeks, months or even years. The fertility of these stallions is unaffected and there are no clinical signs but they can transmit infection to mares during mating or if their semen is used for artificial insemination. WikiVet Article: equine arteritis virus. Link to webpage: Horserace Betting Levy Board Code of Practice for Equine Viral Arteritis. Correct! The shedder stallion is a very important source of equine arteritis virus. During clinical infection, the virus can localise in the accessory sex glands and so can be shed in the stallion's semen for weeks, months or even years. The fertility of these stallions is unaffected and there are no clinical signs but they can transmit infection to mares during mating or if their semen is used for artificial insemination. WikiVet Article: equine arteritis virus. Link to webpage: Horserace Betting Levy Board Code of Practice for Equine Viral Arteritis. Incorrect. Equine infectious anaemia can be shed in semen but it does not persist for long periods in accessory sex glands. The shedder stallion is a very important source of equine arteritis virus. During clinical infection, the virus can localise in the accessory sex glands and so can be shed in the stallion's semen for weeks, months or even years. The fertility of these stallions is unaffected and there are no clinical signs but they can transmit infection to mares during mating or if their semen is used for artificial insemination. WikiVet Article: equine arteritis virus. Link to webpage: Horserace Betting Levy Board Code of Practice for Equine Viral Arteritis.

5

Which family of viruses does the African horse sickness virus belong to? Arteriviridae Reoviridae Paramyxoviridae Adenoviridae Picornaviridae Please select an option Incorrect. The arteriviridae family contains the equine arteritis virus. The correct answer is that the African horse sickness virus is a member of the family Reoviridae. WikiVet Article: Africn Horse Sickness . Correct! African horse sickness virus is a member of the family Reoviridae.WikiVet Article: Africn Horse Sickness Incorrect. The paramyxoviridae family includes the canine distemper virus. The correct answer is that the African horse sickness virus is a member of the family Reoviridae. WikiVet Article: Africn Horse Sickness . Incorrect. The adenoviridae family contains equine adenovirus. The correct answer is Reoviridae from the family reoviridae. WikiVet Article: Africn Horse Sickness . Incorrect. The picornaviridae family includes the equine rhinovirus which causes rhinitis. The correct answer is that the African horse sickness virus is a member of the family Reoviridae. WikiVet Article: Africn Horse Sickness .

6

According to UK Jockey Club rules, how long after the primary vaccination should the third equine influenza vaccination be given? 14 days 365 days 365 - 550 days 150 - 215 days 21 - 92 days Please select an option Incorrect. Outbreaks of equine influenza are most common when high numbers of horses are brought together under stressful conditions, for example at horse shows. Hence the UK Jockey Club has strict rules regarding equine influenza vaccination timing. The second vaccination should be given 21 to 92 days after the first vaccination and the third vaccination 150 to 215 days after the first vaccination. Then the horse should be vaccinated yearly, with the last permissible day being the same day as the previous year's vaccination. Additionally horses may not race until 8 days after the day of the vaccination. WikiVet Article: equine influenza virus. Incorrect. If the third influenza vaccination were to be given 365 days after the first then the primary vaccination course would have to be restarted. Outbreaks of equine influenza are most common when high numbers of horses are brought together under stressful conditions, for example at horse shows. Hence the UK Jockey Club has strict rules regarding equine influenza vaccination. The second vaccination should be given at 21 to 92 days and the third vaccination at 150 to 215 days after the first vaccination. Then the horse should be vaccinated annually, with the last permissible day being the same day as the previous year's vaccination. Additionally horses may not race until until 8 days after each vaccination. WikiVet Article: equine influenza virus. Incorrect. If the third influenza vaccination were to be given 365 to 550 days after the first then the primary vaccination course would have to be restarted. Outbreaks of equine influenza are most common when high numbers of horses are brought together under stressful conditions, for example at horse shows. Hence the UK Jockey Club has strict rules regarding equine influenza vaccination. The second vaccination should be given at 21 to 92 days and the third vaccination at 150 to 215 days after the first vaccination. Then the horse should be vaccinated annually, with the last permissible day being the same day as the previous year's vaccination. Additionally horses may not race until until 8 days after each vaccination. WikiVet Article: equine influenza virus. Correct! Outbreaks of equine influenza are most common when high numbers of horses are brought together under stressful conditions, for example at horse shows. Hence the UK Jockey Club has strict rules regarding equine influenza vaccination. The second vaccination should be given at 21 to 92 days and the third vaccination at 150 to 215 days after the first vaccination. Then the horse should be vaccinated annually, with the last permissible day being the same day as the previous year's vaccination. Additionally horses may not race until until 8 days after each vaccination. WikiVet Article: equine influenza virus. Incorrect. Outbreaks of equine influenza are most common when high numbers of horses are brought together under stressful conditions, for example at horse shows. Hence the UK Jockey Club has strict rules regarding equine influenza vaccination. The second vaccination should be given at 21 to 92 days and the third vaccination at 150 to 215 days after the first vaccination. Then the horse should be vaccinated annually, with the last permissible day being the same day as the previous year's vaccination. Additionally horses may not race until until 8 days after each vaccination. WikiVet Article: equine influenza virus.

7

Approximately what percentage of horses are latently infected with equine herpes virus in the UK? 60% 40% 30% 20% 50% Please select an option Correct! Over 60% of horses are latently infected with equine herpes virus and show antibody as yearlings. WikiVet Article: equine herpes virus. Incorrect. Over 60% of horses are latently infected with equine herpes virus and show antibody as yearlings. WikiVet Article: equine herpes virus. Incorrect. Over 60% of horses are latently infected with equine herpes virus and show antibody as yearlings. WikiVet Article: equine herpes virus. Incorrect. Over 60% of horses are latently infected with equine herpes virus and show antibody as yearlings. WikiVet Article: equine herpes virus. Incorrect. Over 60% of horses are latently infected with equine herpes virus and show antibody as yearlings. WikiVet Article: equine herpes virus.

8

Which virus has been most commonly associated with equine sarcoids? Feline papillomavirus Bovine papillomavirus Ovine papillomavirus Canine papillomavirus Equine papillomavirus Please select an option Incorrect. Feline papillomavirus has not been associated with equine sarcoids. Sarcoids are locally aggressive tumours of the integument, in fact they are the most common skin neoplasm in the horse. The exact pathogenesis of equine sarcoids has not been identified but there is a large amount of evidence to suggest that bovine papillomavirus is, in some way, involved. WikiVet Article: equine sarcoids. Correct! Sarcoids are locally aggressive tumours of the integument, in fact they are the most common skin neoplasm in the horse. The exact pathogenesis of equine sarcoids has not been identified but there is a large amount of evidence to suggest that bovine papillomavirus is, in some way, involved. WikiVet Article: equine sarcoids. Incorrect. Ovine papillomavirus has not been associated with equine sarcoids. Sarcoids are locally aggressive tumours of the integument, in fact they are the most common skin neoplasm in the horse. The exact pathogenesis of equine sarcoids has not been identified but there is a large amount of evidence to suggest that bovine papillomavirus is, in some way, involved. WikiVet Article: equine sarcoids. Incorrect. Canine papillomavirus has not been associated with equine sarcoids. Sarcoids are locally aggressive tumours of the integument, in fact they are the most common skin neoplasm in the horse. The exact pathogenesis of equine sarcoids has not been identified but there is a large amount of evidence to suggest that bovine papillomavirus is, in some way, involved. WikiVet Article: equine sarcoids. Incorrect. Although equine papillomas have a similar appearance to sarcoids, they spontaneously regress, unlike sarcoids. Sarcoids are locally aggressive tumours of the integument, in fact they are the most common skin neoplasm in the horse. The exact pathogenesis of equine sarcoids has not been identified but there is a large amount of evidence to suggest that bovine papillomavirus is, in some way, involved. WikiVet Article: equine sarcoids.

9

Which family of viruses does the equine encephalitis virus belong to? Adenoviridae Picornaviridae Paramyxoviridae Togaviridae Arteriviridae Please select an option Incorrect. The adenoviridae family contains equine adenovirus. The correct answer is that equine encephalitis virus belongs to the family Togaviridae and is typical of the members of this family as it is capable of moving through multiple hosts. Equine encephalitis virus is transferred via a vector, usually a mosquito, to the horse and it also has zoonotic potential. WikiVet Article: equine encephalitis virus. Incorrect. The picornaviridae family includes rhinovirus which causes rhinitis. The correct answer is that equine encephalitis virus belongs to the family Togaviridae and is typical of the members of this family as it is capable of moving through multiple hosts. Equine encephalitis virus is transferred via a vector, usually a mosquito, to the horse and it also has zoonotic potential. WikiVet Article: equine encephalitis virus. Incorrect. The paramyxoviridae family includes hendra virus. The correct answer is that equine encephalitis virus belongs to the family Togaviridae and is typical of the members of this family as it is capable of moving through multiple hosts. Equine encephalitis virus is transferred via a vector, usually a mosquito, to the horse and it also has zoonotic potential. WikiVet Article: equine encephalitis virus. Correct! Equine encephalitis virus belongs to the family Togaviridae and is typical of the members of this family as it is capable of moving through multiple hosts. Equine encephalitis virus is transferred via a vector, usually a mosquito, to the horse and it also has zoonotic potential. WikiVet Article: equine encephalitis virus. Incorrect. The arteriviridae family contains the equine arteritis virus which causes equine viral arteritis (EVA). The correct answer is that equine encephalitis virus belongs to the family Togaviridae and is typical of the members of this family as it is capable of moving through multiple hosts. Equine encephalitis virus is transferred via a vector, usually a mosquito, to the horse and it also has zoonotic potential. WikiVet Article: equine encephalitis virus.