TOKYO -- Deadly viruses responsible for Ebola hemorrhagic fever and other infectious diseases will be imported into Japan by a government laboratory to improve detection and preparedness amid an increasing risk of outbreak with a growing number of foreign visitors before and during the 2020 Tokyo Olympic and Paralympic Games.
The National Institute of Infectious Diseases (NIID) has announced it will import 13 varieties of viruses from five types of hemorrhagic fevers -- Ebola, Lassa, Crimean-Congo, South American and Marburg -- a first for Japan.
"Imported infectious diseases are increasing in Japan as the international transportation network expands and more foreign visitors come here," said NIID head Takaji Wakita, explaining the necessity of intensify measures against deadly diseases.
A record 30 million foreigners have visited Japan in 2018, and the government aims to increase this number to 40 million for the Tokyo Games.
Ebola has a high average fatality rate of around 50 percent. An epidemic that occurred predominantly in West Africa from 2014 killed about 11,300 people. The Democratic Republic of the Congo is still battling an outbreak that began this year. Lassa fever is also common in West Africa, infecting more than 100,000 people yearly. There was a case in 1987 where a person developed Lassa fever in Japan upon returning from Africa.
Currently, Japan can only use genetic codes of limited types of viruses, restricting the varieties of protein samples used to examine people with a suspected infection. By bringing in the pathogens, various types of samples can be created at a level matching international standards. These can be used to detect different kinds of diseases in a single test. This could mean faster and more precise detection of an infection, as well as a method to examine a patient's condition.
However, this is not possible in Japan under the current circumstances without the actual viruses. If imported, the pathogens will allow the examination of effectiveness of a treatment and degree of recovery.
"If we can obtain the viruses, we can take the time to make preparations (to handle infections) beforehand," said NIID Department of Virology 1 Director Masayuki Saijo.
The five types of infectious diseases fall into "category 1" under the "Infectious Disease Surveillance System," meaning that they can only be handled in biosafety level 4 (BSL-4) facilities with the strictest mechanisms to contain the viruses. "Procedures at BSL-4 require careful handling and cannot be rushed," Saijo explained.
NIID's Murayama Branch, based in the suburban Tokyo city of Musashimurayama, is the only laboratory facility in Japan that can handle BSL-4 pathogens. If all goes according to plan, containment and cultivation of the BSL-4 viruses will be managed entirely by the facility.
Researchers there will wear protective suits in the outer dressing room and gowns at the inner dressing room to enter the laboratory, which is surrounded by corridors. When exiting, they must take off these garments and wash their body in a shower room located in between the two dressing rooms to prevent the virus from spreading outside.
The pathogens cannot survive in hot and dry environments, and will gradually die out at room temperature. To prevent this, the viruses will be stored in a triple-layer sealed container inside a freezer at minus 80 degrees Celsius. The container will be transferred to a glove box system that allows researchers to manipulate materials in a sealed space during experiments. In the unlikely event of viruses becoming airborne, HEPA (high-efficiency particle air) filters are installed in the air conditioning units of the laboratory and in the glove box to capture the viruses.
Japan's infectious disease law requires facilities to be designated by the Ministry of Health, Labor and Welfare in order to possess and import category 1 infectious diseases. The Murayama Branch has had permission to have such pathogens since 2015, but intends to seek the ministry's designation for allowing the import of such viruses after coming to an agreement with the municipal government.
However, local residents have expressed discomfort despite the NIID's plan to keep the deadly viruses under strict containment.
"I understand the necessity, but it will pose a greater threat (to residents)," said a 71-year-old male head of a residents' association, after the NIID announced the plan at a liaison council held at the Murayama Branch on Nov. 15. "I don't think an in-depth explanation was provided to the residents, and I'm not convinced."
A 72-year-old man, who belongs to another residents' association, was more understanding of the plan. However, he also requested an "accurate and detailed explanation."
(Japanese original by Takeshi Noda, Medical Welfare News Department)