Global AI Outbreak Situation Update
Since our last issue there have been many reports of avian influenza across the globe. A series of outbreaks of highly pathogenic avian influenza (HPAI) in the USA in poultry, turkeys and wild birds has caused significant losses. As at 23 June 2015 there had been 223 outbreaks in 21 states (6 states in wild birds only) involving the disposal of 48,091,293 birds. To date, the US Department of Agriculture (USDA) has deployed nearly 400 employees and 2,100 contractors to work around the clock in states impacted by the outbreak. USDA has also identified more than $160 million in indemnity payments to producers.
The outbreaks have involved the destruction/death of more than 11% of the USA poultry population and resulted in major difficulties in carcass disposal. The viruses are very virulent and birds in some affected flocks are reported to be dying faster than they can be destroyed.
In early 2014, a novel avian influenza (H5N8) virus emerged in poultry and many wild bird species in Asia. Multiple outbreaks of HPAI in poultry worldwide were caused by viruses closely related to this novel H5N8 virus. They include, for example, H5N1 in China and Vietnam; H5N2 in North America and Taiwan; H5N6 in China, Laos and Vietnam; and H5N8 in China, Europe, Japan, North America, South Korea and Taiwan. These viruses have diverse genetic lineages but can be grouped under the same Eurasian H5 clade 22.214.171.124. These viruses are not known to easily cause disease in humans although 3 humans infected with H5N6 in China have been reported since late 2014.
The socioeconomic and animal health impact of the multiple H5N2 and H5N8 HPAI outbreaks in commercial and backyard poultry flocks worldwide has been serious. Trade disruptions and egg rationing have been reported from the USA. The Eurasian H5 clade 126.96.36.199 was not found in the USA before 2014 and the USDA has publicly expressed concerns that infection may be a threat to the industry for many years to come if the virus remains endemic in wild birds.
Wild birds infected with these HPAI viruses are believed to play a role in the recent global or within-country spread of various H5 HPAI viruses. A wider range of wild bird species has now been shown to carry HPAI viruses. The assumption that some migratory wild birds, particularly waterfowl species, carrying HPAI viruses without being clinically affected are able to travel long distances is yet to be proven, but would explain the recent global distribution of H5 virus outbreaks. Concern about inadequate biosecurity practices as a key risk factor for the spread of these HPAI viruses in poultry species has also been raised by affected countries.
The risk of Eurasian H5 HPAI viruses, including the H5N2 and H5N8 strains, to Australia remains low. This assessment takes into account various risk factors including the entry routes of migratory birds and the likelihood of their contact with poultry. The consequences of potential establishment and spread following an incursion may, however, now be greater given the observed difficulty of eradicating or controlling the spread of H5N8, H5N2 and H5N1 in overseas commercial flocks, particularly those in North America.
Reports since the last issue:
A new strain currently causing a large outbreak of
feline influenza in many states in the USA.
Cases reported in poultry in Bhutan, Burkina Faso, Cote d’Ivoire, Egypt, Ghana, India, Indonesia, Iran, Israel, Niger, Nigeria, Palestine, Russia, Turkey, Vietnam; wild birds in Bulgaria, Romania and Russia and in humans in China and Egypt.
Cases reported in poultry in Belize, Canada, The Netherlands, Taiwan and the USA and wild birds in Taiwan and the USA.
Cases reported in poultry in Vietnam and wild birds in Hong Kong and China.
Cases reported in poultry in Germany.
Cases reported in wild birds in Canada, Japan and Sweden and poultry in Taiwan and the USA.
Reported in humans in China.
Cases reported in poultry in the USA and poultry and wild birds in Mexico.
Low pathogenic virus in poultry in The Netherlands and Germany.
Further human cases were reported in China.
Further cases reported in humans and poultry in Egypt and wild birds in the USA.
Reported in humans in China.
Middle East Respiratory Syndrome (MERS)
Cases of the
novel coronavirus MERS-CoV continue to be reported. As of 5 June 2015, 1,211 cases have been confirmed with 492 deaths since 2012 – a higher human death toll than from H5N1 over 10 years. Cases were recently reported from Saudi Arabia, Qatar, Iran, United Arab Emirates, Oman, South Korea, Hong Kong and Thailand. The 172 cases and 27 deaths in South Korea started with the return of an aged man from the Middle East. Subsequent cases occurred in family members, health care staff and other patients with one case travelling to China.
Since the last issue
outbreaks of anthrax have been reported in Argentina (cattle), Guinea (livestock), India (cattle, pigs, elephants and humans), Italy (goats), Kenya (cattle and humans), Norway (cattle), Russia (bovine, ovine, humans), Turkey (bovine and humans), USA (cattle), Zambia (cattle and humans). This disease is frequently reported worldwide and needs to be on your list of differential diagnoses in cases of sudden death of livestock.
Foot and mouth disease (FMD)
FMD has recently been reported in Algeria in sheep (O*), Bahrain in cattle, Mauritania in cattle (SAT 2), Mozambique in cattle, Namibia in cattle (SAT 2), South Korea in pigs (O), Taiwan in cattle (A), Vietnam in cattle and Zimbabwe in cattle. (* indicates serotype where reported).
A recent article reports an outbreak of FMD (serotype O) in
Asiatic black bears in Vietnam in 2011. The bears had indirect contact with livestock.
Disease screening in Scotland has revealed 7 of 31 flocks tested were
infected with this lentivirus. MV causes ill thrift and signs of pneumonia. It is spread by the movement of infected animals and through colostrum. It is reported to be wide spread in UK flocks. How many cases of sheep with laboured breathing and ill thrift have you investigated recently and did you check for MV?
Peste des petits ruminants
FAO and OIE recently convened a meeting of 15 countries which agreed to collaborate on a plan to eradicate PPR by 2030. PPR is estimated to cause $2 billion in losses each year in Africa, the Middle East and Asia. 80% of the world’s 2.1 billion small ruminants live in affected areas.
Anaplasmosis – new species
Chinese researchers have reported that the newly identified
Anaplasma capra, found to infect goats, can also affect humans resulting in varied signs (fever, headache, malaise, dizziness, myalgia, rash, lymphadenopathy and gastrointestinal symptoms). It is spread via the taiga tick, which is also found in Russia, Japan and Asia.
Sheep and goat pox has recently been reported in sheep in Israel, Kazakhstan and Mongolia. Camel pox was suspected in Kharai camels in Pakistan.
Akhmeta poxvirus, a novel orthopoxvirus was detected in three patients in Georgia in 2013. The men all had contact with cows. Serologic evidence for the virus was then detected in the patients’ herd and in captured rodents and shrews.
66% of hospitalised malarial cases
reported in Sabah, Sarawak and Kelantan, Malaysia in 2014 were due to
P.knowlesi, which is spread from macaque monkeys by
Exclusion testing is undertaken when a clinical syndrome is present and an emergency animal disease is included in the differential diagnosis. Exclusion testing is undertaken by the jurisdiction at no cost to the owner and no imposition of legal restrictions unless the there is strong reason to suspect the disease is present or the laboratory diagnosis is positive for the EAD.
Exclusion testing is important as it demonstrates to our trading partners that we are looking for the presence of EADs. If you include the possibility (even remotely) of an EAD in your differential diagnosis you should contact your local government veterinary officer and discuss arrangements for an exclusion test. Detailed histories will be required.
Merck Animal Health recently added an
educational video to their website on shipping and transportation of cattle. It is aimed to help farmers understand cattle behaviour and reduce stress on animals.
A new manual for
has recently been released.