The novel strain of bird flu, which sickened 108 people and killed 22 in China, has now spread to Taiwan, according to the World Health Organization (WHO).
The first case was reported outside of mainland China when a 53-year-old businessman in Taiwan was diagnosed with H7N9, one of the "most lethal" strains of avian influenza.
Health Department Minister Wen-Ta Chiu said the patient was hospitalized three days after he visited Suzhou in the Jiangsu Province of China.
The Taiwanese Centers for Disease Control confirmed it was a H7N9 case.
"The patient is currently in a severe condition and being treated in a negative-pressure isolation room," the Taiwanese CDC said in a statement Wednesday.
“On April 9, he returned to Taiwan from Shanghai,” the statement read. “According to the case, he had not been exposed to birds and poultry during his stay in Suzhou and had not consumed undercooked poultry or eggs. On April 12, he developed fever, sweating, and fatigue, but no respiratory or gastrointestinal symptoms. On April 16, he sought medical attention at a clinic when he developed high fever and was transferred to a hospital by the physician. He was then hospitalized in a single-patient room for further treatment.”
The patient’s conditioned worsened. “He was then intubated due to respiratory failure and placed in the negative-pressure isolation room in the intensive care unit.”
"This is definitely one of the most lethal influenza viruses we have seen so far," Dr. Keiji Fukuda, assistant director-general for health security at WHO, said on Wendesday at a Beijing briefing.
The WHO previously stated that there is no evidence that H7N9 can pass from human to human. Health officials believe the virus is transmitting readily from birds to humans.
"We think this virus is more transmissible to humans than H5N1," Fukuda said.
Scientists have found it difficult to track the virus because there does not seem to be any visible illness in infected birds. There is no way to tell how many people could have been infected without showing signs of illness either.
"The situation remains complex and difficult and evolving," Fukuda said. "When we look at influenza viruses, this is an unusually dangerous virus for humans."
Fukuda said in a statement there isn’t enough data to "conclude there is person to person transmission.”
Dr. Joseph Bresee of the U.S. Centers for Disease Control and Prevention (CDC) said the virus could be passing from person to person, but that possibility has not yet been verified.
Mike Shaw of the CDC said they found mutation in the H7N9 virus, which could lead to an antibiotic resistant strain.