每日跟讀#476:What is African swine fever and how does it spread?
What is African swine fever?
African swine fever (ASF) is a highly contagious viral pig disease. The most common symptoms of the virus in its acute form are a high temperature and loss of appetite; other symptoms include vomiting, diarrhea, and difficulty with breathing and standing. There is no treatment for the disease, some versions can have a 100 percent mortality rate in certain circumstances. It is not the same as swine flu.
How does it spread?
ASF can be transmitted through direct contact with infected animals. Wild boar have been identified by some national governments as one of several possible culprits for the recent spread. It can also spread via insects such as ticks.
But the virus can also survive several months in processed meat, and several years in frozen carcasses, so meat products are a particular concern for cross-border transmission. It is believed that the disease was initially brought from east Africa to Georgia by contaminated pig products. Last month, a packet of sausages confiscated at a Japanese airport from a traveler arriving from China were found to contain the virus. Similar discoveries have been made in South Korea, according to reports.
What happens when it is found?
Cases must be reported to the authorities. In most countries, this will trigger quarantine measures and a cull of the affected herd. However, there is anxiety among experts that in some cases farmers — or even whole countries — may cover up or delay reporting the illness. In May, for example, Belarus was accused of covering up ASF among its pigs. The Belarus government denied the claims.
Can it be caught by humans?
Humans cannot contract ASF. However the head of the Russian epidemiology service, chief state sanitary doctor Gennady Onishchenko, has warned that pig physiology is close to human physiology, and that future mutations of the virus may therefore become dangerous to human beings too.
Why are people worrying about it now?
For many years ASF was found mainly in Africa, although there was an outbreak in Europe in the 1950s which took several decades to eradicate. In 2007, however, the virus was detected in Georgia, and despite co-ordinated efforts it has since spread widely, initially through eastern Europe and Russia, and more recently into western Europe, when wild boar in Belgium were found to have the disease. The virus has now jumped to China, home to half the world’s domestic pigs, and appears to be proliferating rapidly. According to one report there have been 41 outbreaks since the first notification in early August.
Are there any vaccines or cures on the horizon?
The Roslin Institute is looking at gene editing to make pigs resistant to ASF. An international coalition of scientists is urgently investigating vaccines.
Source article: http://www.taipeitimes.com/News/lang/archives/2018/11/28/2003705033/2