Apr 29, 2013 (CIDRAP News) – The reach and number of H7N9 infections in China continued to expand over the past 3 days, with Hunan province reporting its first case and four others reporting six more, lifting the outbreak's total to 126, according to the latest official and media reports.
The detection of the case in Hunan province moves the scope of the human infections farther south and toward the center of the country and follows recently reported H7N9 infections in another more southern area, neighboring Jiangxi province.
Among the newly reported cases are some middle-aged adults, plus a 4-year-old boy from Shandong province whose illness reflects another family illness cluster.
In addition to the new cases, two more people died from H7N9 infections, both of which were cases reported earlier from Jiangsu province, the World Health Organization (WHO) said today, based on a weekly update from China's National Health and Family Planning Commission. The deaths push the outbreak's fatality count to 24.
Illness-onset dates for the new cases reported by the WHO, which include some previously reported cases over the past week as well as the most recent ones, range from Mar 8 through Apr 27, signaling that the outbreak is ongoing.
Though China's Center for Disease Control and Prevention (China CDC) has transitioned to weekly reporting of cases, Hong Kong's Centre for Health Protection (CHP) is still issuing regular updates that include the patients' conditions.
The patient from Hunan province is a 64-year-old woman who is hospitalized, according to the CHP. The woman started having symptoms on Apr 14, which was 4 days after she had been exposed to poultry, Xinhua, China's state news agency, reported on Apr 27.
Fujian province reported its second H7N9 infection, in an 80-year-old man who started having symptoms on Apr 17 and is hospitalized in critical condition, according to the WHO and CHP.
The new cases from Jiangxi province involve an 80-year-old man who got sick on Apr 21 and is in stable condition and a 31-year-old woman who got sick on Apr 23 and is in serious condition, according to the WHO and CHP. Another patient is a 54-year-old man who is hospitalized, according to the CHP.
Zhejiang province's latest case is in a 38-year-old man who started having symptoms on Apr 18 and is hospitalized in serious condition, according to the WHO and CHP.
Meanwhile, the 4-year-old boy is the son of Shandong province's first H7N9 patient, a 36-year-old man, according to an update today from the CHP. The boy is hospitalized in stable condition.
Infections in family member can represent shared exposure to the same virus source, and complex investigations are needed to confirm human-to-human transmission. Health officials have said they expect to see some limited transmission, especially in family members who have extensive contact with each other.
So far there is no sign of sustained person-to-person transmission that would signal a greater threat, and health officials are continuing to closely monitor the contacts of confirmed cases, the WHO said.
On the veterinary front, testing at a poultry market in Dungun City in Guangdong province has apparently turned up one positive H7N9 sample in a chicken, according to a microbiologist from China who monitors Chinese media reports on behalf of CIDRAP News.
The finding, from a batch of 130, was confirmed by the Guangdong Provincial Animal Disease Control Center on Apr 27 and has been reported to the China CDC. So far the disease has not been detected in market workers, and all poultry in the market have been culled.
The finding is concerning, given that humans seem to be sentinels for the H7N9 virus, so if it's in poultry, there is a high likelihood that it is also circulating in humans, the scientist told CIDRAP. So far no human cases have been reported from Guangdong province.
In an epidemiologic update today, the European Centre for Disease Prevention and Control (ECDC) said China has intensified investigations into possible sources and reservoirs for the virus, but so far the source and mode have not been confirmed, though the most likely scenario is close contact with poultry or poultry products.
The ECDC said it expect sporadic cases to increase in number and geographic spread in China and possibly neighboring countries over the coming weeks. Taiwan is the only area outside China's mainland that has confirmed an H7N9 case, in a man who had recently traveled to a province that has reported several infections.
Apr 29 WHO update
Apr 27 Xinhua story
Apr 29 CHP statement
Apr 28 CHP statement
Apr 27 CHP statement
Apr 29 ECDC update