On 15 January 2020, the Ministry of Health, Labour and Welfare, Japan (MHLW) reported an imported case of laboratory-confirmed 2019-novel coronavirus (2019-nCoV) from Wuhan, Hubei Province, China.
The case-patient is male, between the age of 30-39 years, living in Japan.
The case-patient travelled to Wuhan, China in late December and developed fever on 3 January 2020 while staying in Wuhan. He did not visit the Huanan Seafood Wholesale Market or any other live animal markets in Wuhan. He has indicated that he was in close contact with a person with pneumonia.
On 6 January, he traveled back to Japan and tested negative for influenza when he visited a local clinic on the same day.
On 10 January 2020, due to his continued symptoms of cough, sore throat and fever, he visited a local hospital and was found to have abnormal chest x-ray with infiltrates. He was admitted to the hospital on the same day and had remained febrile until 14 January. On 14 January, his attending doctor notified the case to a local public health authority under the surveillance system for “Unidentified Serious Infectious Illness”.
Samples were collected and sent to the National Institute of Infectious Diseases (NIID), and at NIID, polymerase chain reaction (PCR) testing and sequencing was performed twice, which identified very small amount of 2019-nCoV RNA on 15 January 2020.
On 15 January, the case-patient was afebrile and was discharged from hospital. Currently, he is staying at home in a stable condition.
Public health response
- Contact tracing and other epidemiological investigations are underway by the local health authorities in Japan;
- The Japanese Government has scaled up a whole-of-government coordination mechanism on the 16 January;
- The MHLW has strengthened surveillance for undiagnosed severe acute respiratory illnesses since the report of undiagnosed pneumonia in Wuhan, China;
- From 6 January, MHLW requested local health governments to be aware of the respiratory illnesses in Wuhan by using the existing surveillance system for serious infectious illness with unknown etiology;
- NIID is supporting local authorities on epidemiologic investigations including contact tracing;
- Quarantine and screening measures have been enhanced for travelers from Wuhan city at the point of entries since 7 January;
- NIID established an in-house PCR assay for nCoV on 16 January;
- Revision of the risk assessment by NIID is being conducted, including case definition of close contacts;
- The public risk communication has been enhanced;
- A hotline has been established among the different ministries in the government;
- The MHLW is working closely with WHO and other related Member States to foster mutual investigations and information sharing.
WHO risk assessment
This was the second of three exported cases of novel coronavirus from Wuhan city, China. Since the initial report of cases in Wuhan city on 31 December 2019, and as of 12 January 2020, 41 laboratory-confirmed cases of nCoV infection, including 2 deaths in cases with underlying medical conditions have been reported to WHO. Two cases have been reported from Thailand.
The source of the outbreak is still under investigation in Wuhan. Preliminary investigations have identified environmental samples positive for nCoV in Huanan Seafood Wholesale Market in Wuhan City, however some laboratory-confirmed patients did not report visiting this market. To date, there is no reported infection among healthcare workers in China, Thailand or Japan. No additional cases have been reported since 3 January in China.
Additional investigations are needed to determine how the patients were infected, whether human-to-human transmission has been observed, mode(s) of transmission, the clinical spectrum of disease, and the extent of infection, including presence of subclinical cases that are undetected with current surveillance.
It is critical to review all available information to fully understand the extent of transmissibility between people and likelihood of zoonotic spillover.
Although the source of the novel coronavirus causing this cluster of pneumonia and the mode(s) of transmission are unknown, it would be prudent to remind populations and health workers of the basic principles to reduce the general risk of transmission of acute respiratory infections:
- Avoiding close contact with people suffering from acute respiratory infections;
- Frequent hand-washing, especially after direct contact with ill people or their environment;
- Avoiding unprotected contact with farm or wild animals;
- People with symptoms of acute respiratory infection should practice cough etiquette (maintain distance, cover coughs and sneezes with disposable tissues or clothing, and wash hands);
- Within healthcare facilities, enhance standard infection prevention and control practices in hospitals, especially in emergency departments;
- WHO does not recommend any specific health measures for travelers. In case of symptoms suggestive of respiratory illness either during or after travel, the travelers are encouraged to seek medical attention and share their travel history with their health care provider. Travel guidance has been updated.
Health authorities should work with travel, transport and tourism sectors to provide travellers with information to reduce the general risk of acute respiratory infections via travel health clinics, travel agencies, conveyance operators and at points of entry.
WHO has provided interim guidance for novel coronaviruses
WHO advises against the application of any travel or trade restrictions on Japan based on the information currently available on this event.
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