Taiwan reports first H7N9 case outside of China

Apr 24, 2013 (CIDRAP News) – Taiwan health officials today announced that a 53-year-old man who had recently traveled to China is hospitalized in critical condition with a novel H7N9 infection, the first such case to be detected outside of China.

Taiwanese health officials also said three health workers who helped care for the man have had upper respiratory symptoms and are being followed closely.

The latest outbreak development came on a day when China's mainland reported no new H7N9 cases, US and European officials took new preparedness steps with diagnostic testing, and a joint expert team from the World Health Organization (WHO) wrapped up their meetings with their Chinese counterparts and shared their findings and initial recommendations.

The man from Taiwan had regularly traveled to Suzhou in Jiangsu province, an area of eastern China in which several other H7N9 cases have been reported and the virus has been found, mainly in live bird market settings. A statement today from Taiwan's Centers for Disease Control (Taiwan CDC) said the man's most recent trip to Suzhou was between Mar 28 and Apr 9. The man said he had no contact with poultry or other birds and had not eaten undercooked eggs or poultry.

Three days after he returned from China he started having symptoms, including fever and fatigue. The man is a hepatitis B carrier who has hypertension, according to Taiwan CDC. His condition worsened, and on Apr 16 he was hospitalized, isolated, and treated with oseltamivir (Tamiflu).

A few days later his illness became more severe and he was transferred to another medical center where he was put on a ventilator and placed in a negative-pressure room. At the two hospitals his throat swab samples were negative for the H7N9 virus, but on Apr 22 a sputum sample tested positive for influenza A, and follow-up tests by the National Influenza Center detected the H7N9 virus.

The confirmation pushes the total number of H7N9 cases to 109, which includes 22 deaths.

Health officials are following up on 139 people who had contact with the man, most of whom are healthcare workers. Three who did not wear appropriate personal protective equipment (PPE) have not shown any symptoms. Three workers who did have respiratory symptoms, however, all wore appropriate PPE, Taiwan CDC said.

WHO spokesman Gregory Hartl urged caution in speculating about the healthcare worker infections, because no information is available yet on any test results, the Toronto Star reported today. He said other cases of flulike symptoms were seen in mainland China healthcare workers, but all the tests were negative for H7N9.

Regarding the detection of the first case outside of China, Hartl told CIDRAP News that the new development doesn't change its risk assessment, because the man apparently contracted his infection in Jiangsu or Shanghai, where several human infections from environmental and animal sources have already been seen.

"We expected to see instances of cases elsewhere because of travel, so this case does not surprise us. We could well see more such cases," he said.

Officials take testing steps
Some countries have issued warnings about the risk of imported H7N9 cases in travelers from China, which has prompted public health officials in some areas to actively look for cases in people who get sick with respiratory infections after traveling to the country.

The US Centers for Disease Control and Prevention (CDC) has said it is monitoring for people who get sick after traveling to China, and it has started posting resources, including antiviral guidance, to help clinicians identify and manage suspected or confirmed cases.

Today the CDC took another preparedness step by announcing that it has developed diagnostic test materials to detect the new virus. They include rRT-PCR (real-time reverse-transcriptase polymerase chain reaction) reagents, controls, and a test protocol. The materials are available from the Influenza Reagent Repository Web site. The agency said the testing should be performed only if the patient meets the clinical and epidemiologic criteria for suspect cases.

The CDC is also making the test kit available to international public health labs, with priority going to countries in the part of the world where cases have been detected. However, it said all requests from National Influenza Centers and national public health labs will be processed as soon as possible.

On Apr 22 the Food and Drug Administration issued an emergency use authorization for the H7N9 diagnostic test, which the CDC said is a preparedness measure and not a signal that a public health emergency exists.

The European Centre for Disease Prevention and Control (ECDC) said in an Apr 15 epidemiologic update that the H7N9 outbreak could expand to neighboring areas and that isolated cases could pop up in Europe. It urged countries to be prepared to detect and diagnose the disease.

In a related development, the ECDC today issued a technical briefing to help virology labs assess their options for establishing assays for screening and confirming H7N9 infections. The guidance also provides labs with a list of preparedness measures to consider, updates them on the current methods for detecting the virus by RT-PCR testing, gives H7 hemagglutinin assay validation criteria, and shares information about positive controls.

Expert group shares findings, recommendations
In China today, a team of international and Chinese experts wrapped up its mission to assess the H7N9 outbreak, and members addressed the media in Beijing. They began their work on Apr 19, traveling to poultry markets and meeting with officials in Beijing and Shanghai, the WHO said today in a press release.

Keiji Fukuda, MD, the WHO's assistant director-general for health security and environment, lauded China's response to the outbreak and its open exchange of information with the international community, according to a transcript of his speech at the briefing, which was posted on the WHO's Web site. He also shared some of the group's findings and aired its initial recommendations.

So far the source of the virus appears to be birds, especially poultry and the environment contaminated by the virus, he said. "The risk of infections appears most concentrated in live-poultry markets."

Though a few family clusters have been found, experts found no evidence to conclude that person-to-person transmission is occurring and that no sustained transmission has been found. "We want to note that if limited person-to-person transmission is demonstrated in the future, it will not be surprising," Fukuda said. "Enhancing surveillance is the way to early detect such occurrence."

Among several recommendations, the most urgent is to determine the source of the human H7N9 infections and take immediate actions to curb the spread of the virus to protect human and animal health, Fukuda said.

The team said it's critical to keep a high level of alert and preparedness for the virus, even though the number of human cases might drop over the summer, because the virus poses a serious health risk and many key questions about it are still unanswered.

The experts advised China to continue to conduct and strengthen surveillance in humans and animals in all of the country's provinces to flag changes that might show geographic spread of the new virus or that it's gaining the ability to more easily infect humans.

See also:

Apr 24 Taiwan CDC statement

Apr 24 Toronto Star story

Apr 24 CDC statement on H7N9 diagnostics

Apr 24 ECDC statement on diagnostic preparedness

Apr 24 Fukuda opening statement

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