TOKYO – Deadly viruses responsible for Ebola hemorrhagic fever and other infectious diseases will be imported to Japan by a government laboratory to improve detection and preparedness in the face of a growing risk of an epidemic with an increasing number of foreign visitors before and during the Tokyo 2020 Olympic and Paralympic Games.

The National Institute of Infectious Diseases (NIID) has announced that it will import 13 varieties of viruses from five types of hemorrhagic fevers – Ebola, Lassa, Crimea-Congo, South America and Marburg – a first in Japan.

“Imported infectious diseases are increasing in Japan as the international transport network expands and more and more foreign visitors come here,” said NIID director Takaji Wakita, explaining the need to step up measures against deadly diseases.

A record 30 million foreigners visited Japan in 2018, and the government aims to increase that number to 40 million for the Tokyo Games.

Ebola has a high average death rate of around 50 percent. An epidemic that occurred mainly in West Africa from 2014 killed around 11,300 people. The Democratic Republic of the Congo continues to grapple with an epidemic that began this year. Lassa fever is also common in West Africa, infecting more than 100,000 people per year. 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 for limited types of viruses, limiting the varieties of protein samples used to examine people suspected of infection. By introducing the pathogens, various types of samples can be created at a level corresponding to international standards. These can be used to detect different types of diseases in a single test. This could mean faster and more accurate detection of an infection, as well as a method of examining a patient’s condition.

However, this is not possible in Japan under the current circumstances without the real viruses. If imported, pathogens will be used to examine the effectiveness of a treatment and the degree of recovery.

“If we can get the viruses, we can take the time to prepare (to manage the infections) ahead of time,” said Masayuki Saijo, director of the Department of Virology 1 at NIID.

The five types of infectious diseases fall under “Category 1” of the “Infectious Disease Surveillance System”, which means that they can only be treated in biosafety level 4 (BSL-4) facilities with the appropriate mechanisms. strictest to contain viruses. “The procedures at BSL-4 require careful handling and cannot be rushed,” Saijo explained.

The Murayama branch of NIID, based in the suburban Tokyo city of Musashimurayama, is the only laboratory in Japan capable of processing BSL-4 pathogens. If all goes as planned, containment and cultivation of BSL-4 viruses will be fully managed by the facility.

Researchers will wear protective suits in the outdoor locker room and gowns in the indoor locker room to enter the laboratory, which is surrounded by corridors. On leaving, they must remove these clothes and wash their body in a shower room located between the two changing rooms to prevent the virus from spreading outside.

Pathogens cannot survive in hot, dry environments and will gradually die out at room temperature. To avoid this, viruses will be stored in a sealed triple-layer 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 the experiments. In the unlikely event that viruses spread through the air, HEPA (High Efficiency Particle Air) filters are installed in the laboratory air conditioning units 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 own and import Category 1 infectious diseases. Murayama branch is authorized to have such pathogens since 2015, but intends to seek the designation of the ministry to authorize the importation of these viruses after reaching an agreement with the municipal government.

However, local residents have expressed unease despite NIID’s plan to keep the deadly viruses under strict containment.

“I understand the need, but it will pose a greater threat (to residents),” said a 71-year-old man who heads a residents’ association, after NIID announced the plan at a council liaison held at the Murayama branch on November 15. “I don’t think a thorough explanation was provided to the residents, and I’m not convinced.”

A 72-year-old man, who belongs to another residents’ association, was more sympathetic to the plan. However, he also asked for a “precise and detailed explanation”.

(Japanese original by Takeshi Noda, Medical Welfare Information Service)