The Yomiuri ShimbunIt is hard to contain a virus once it spreads. Yet expansion of viral infections must be stemmed.
Swine fever, also known as hog cholera, which has broken out sporadically since last September in Gifu Prefecture, has spread to Aichi, Osaka, Shiga and Nagano prefectures.
The Agriculture, Forestry and Fisheries Ministry sent experts and officials to Gifu Prefecture as a cautionary step but failed to stem the spread of infection. Epidemic prevention arrangements against swine fever should be revamped swiftly.
Swine fever virus does not infect humans, but if pigs are infected with the virus, they will develop a fever and other symptoms, eventually dying in some cases. Its infectiousness is strong, too. It is necessary to pay utmost attention to such precautionary measures as ensuring thorough disinfection when people enter and leave pig farms and not using raw feed, which has a high risk of infection.
Caution is also needed to prevent infection via wild boars. In Gifu Prefecture, more than 100 boars were confirmed to have been infected. It is indispensable to take measures to prevent the movement of boars, including installing fences.
Steps to deal with harmful rumors are indispensable, too. Eating infected pigs will not affect human health. Even so, infected pig meat will never be marketed. Consumers should respond calmly.
A pig farm in Aichi Prefecture is said to be the source for the spread of swine fever to wide areas. Piglets born on that farm were infected with the swine fever virus and infection spread on farms to which the infected piglets were shipped. The virus is said to be the same one found in infected pigs in Gifu Prefecture. It is imperative to identify the infection route and use the findings to work out countermeasures.
Caution needed against ASF
Abnormal conditions were observed among the piglets before their shipment. But officials in charge of prevention of epidemics at the farm in question and the Aichi prefectural government did not recognize that the piglets had developed symptoms of swine fever. It has to be said that they lacked a sense of urgency. The central government should stress anew the importance of preventive measures.
Swine fever broke out in Japan for the first time in 1887. Later epidemics also broke out, but measures taken by the industry proved successful enough that there were no epidemics at all from 1993 onward. The government declared in 2007 that the country had become free of swine fever.
Taking advantage of the Economic Partnership Agreement with the European Union that took effect this month, the government aims to expand exports of pork and other relevant products. Being a country free of the disease is a prerequisite for holding trade negotiations. It is feared that the current outbreak of swine fever will have an adverse effect on exports of Japan-raised pigs that are very popular in Asia.
Vaccination is an effective way to stem the spread of infection, but asymptomatic infections are feared to continue. Procedures for Japan to be recognized again as an infection-free country will be protracted. First of all, it is crucial to make an all-out effort to contain the spread of infection at its initial stage.
Caution is also required against African swine fever (ASF), which has been on a rampage in China and elsewhere. The ASF pathogen is different from that of the swine fever that broke out Japan this time. No effective vaccine is available. If ASF spreads to Japan, it will deal a great blow.
The infectiousness of ASF is said to exceed that of the swine fever currently hitting Japan. The ASF virus does not die out easily and there are cases in which it has survived in raw ham for as long as 10 months. It is imperative to call attention to ASF and take all possible quarantine steps with a view to preventing tourists from bringing it into Japan.