World's first human case of H7N4 avian flu reported in China

The first human case of the H7N4 strain of avian influenza has been reported in China, ...

Posted: Feb 15, 2018 8:31 PM
Updated: Feb 15, 2018 8:31 PM

The first human case of the H7N4 strain of avian influenza has been reported in China, Hong Kong's Centre for Health Protection announced Wednesday.

A 68-year-old woman living in Jiangsu Province in eastern China, near Shanghai, had contact with live poultry before she began developing pneumonia-like symptoms December 25. She was admitted to a hospital January 1 and was discharged after successful treatment January 22.

The 68-year-old woman was hospitalized in January

Wild aquatic birds are the natural hosts for most influenza type A viruses

H7 virus infections in humans are not common and typically cause mild to moderate illnesses

It was not until February that the virus was identified as being of avian origin, according to a report from the Chinese Center for Disease Control and Prevention.

The patient's close contacts were under "medical surveillance," and none developed signs or symptoms of illness. But health officials are asking the public to remain vigilant and to practice good hygiene.

"Based on the seasonal pattern, the activity of avian influenza viruses is expected to be higher in winter," the Centre for Health Protection said. Travelers to affected areas "should be alert to the presence of backyard poultry when visiting relatives and friends. They should also avoid purchasing live or freshly slaughtered poultry, and avoid touching poultry/birds or their droppings."

Most avian flu strains are not transmitted to humans. The H7N4 avian flu strain was first identified among chickens in Australia in 1997, according to the World Health Organization. But this is the first known human case of this strain.

"Our surveillance mechanisms -- the mechanisms that we use to detect influenza strains and pick up these unusual strains -- is vastly more sophisticated now than it has been in the past," said Dr. William Schaffner, an infectious disease specialist at the Vanderbilt University School of Medicine. "It's a testimony to the comprehensiveness of our surveillance."

According to the US Centers for Disease Control and Prevention, there are four types of influenza viruses: A, B, C and D. Wild aquatic birds are the natural hosts for most influenza type A viruses, although two subtypes (H1N1 and H3N2) are circulating humans as well. Type B influenza viruses are present only in humans.

As with most influenza viruses, the H7N4 strain appears to spread by respiratory droplets that may be inhaled by people who spend a great deal of time around poultry.

"On occasion, this virus can get in and find receptors that are actually rather deep in the bronchial tubes and, once that happens, you can get illness, but it's rare," Schaffner said.

According to a statement from China's Ministry of Health, 28 people who had been in contact with the infected person were monitored and did not show any signs of infection.

"She's what we call a dead-end infection," Schaffner added. "It doesn't go anywhere from her."

Type A viruses can be further subdivided based on two proteins -- hemagglutinin (HA) and neuraminidase (NA) -- found on the surface of the virus. There are 18 known HA subtypes and 11 known NA subtypes, according to the CDC.

H7 virus infections in humans are not common and typically cause milder or more moderate illnesses than other avian strains, with symptoms such as conjunctivitis and upper respiratory infections, according to the CDC. The most frequently identified H7 strain strain in humans is H7N9, with the first human infections reported in China in 2013.

According to the CDC, 1,565 people have been infected with the H7N9 strain since 2013; 39% have died.

But according to Schaffner, the H7N4 case probably poses no serious threat to humans.

"I think the risk is really zero at the present time," he said. "We ought to take some comfort that we, in collaboration with the World Health Organization, have a distant early warning system that is picking up these cases and monitoring them very, very closely.

"We watch all this very closely, because if one of these strains happened to be able to pick up the genetic capacity to be transmitted from person to person readily, we would be on the threshold of a new pandemic."

According to Schaffner, treatment for infection with avian flu strains typically includes symptom management, which can include fever-reducing medication, hydration and antiviral medications.

"At the moment, the illnesses that (avian flu strains) tend to cause seem to be more severe," he said. "But they still respond to prompt treatment."

Indiana Coronavirus Cases

(Widget updates once daily at 8 p.m. ET)

Confirmed Cases: 33558

Reported Deaths: 2110
CountyConfirmedDeaths
Marion9616571
Lake3538185
Cass15897
Allen145168
St. Joseph124834
Elkhart116328
Hendricks116171
Hamilton115693
Johnson1093108
Madison58559
Porter51627
Bartholomew50034
Clark49241
LaPorte42423
Howard39526
Tippecanoe3903
Jackson3791
Delaware37736
Shelby36822
Hancock32728
Floyd31839
Boone30935
Morgan27824
Vanderburgh2652
Montgomery23517
White2318
Decatur22431
Clinton2231
Noble21121
Grant20621
Harrison19221
Dubois1923
Henry16910
Greene16824
Monroe16612
Warrick16628
Dearborn16621
Vigo1648
Lawrence15423
Miami1411
Putnam1367
Jennings1304
Orange12522
Scott1193
Kosciusko1111
Franklin1098
Ripley1086
Carroll922
Marshall901
Daviess8516
Steuben812
Newton7710
Wayne776
Fayette767
Wabash762
LaGrange712
Jasper651
Washington521
Jay500
Fulton481
Clay471
Rush462
Randolph463
Pulaski460
Jefferson431
Whitley393
Starke363
Sullivan341
Owen341
Brown331
DeKalb331
Perry310
Benton300
Knox290
Wells280
Huntington272
Tipton251
Crawford240
Blackford242
Fountain202
Switzerland200
Spencer191
Parke170
Posey160
Gibson142
Adams131
Ohio130
Warren121
Martin110
Vermillion100
Union80
Pike60
Unassigned0164

Illinois Coronavirus Cases

(Widget updates once daily at 7 p.m. CT)

Confirmed Cases: 117455

Reported Deaths: 5270
CountyConfirmedDeaths
Cook762663570
Lake8063287
DuPage7543362
Kane6188170
Will5442269
Winnebago215654
McHenry151471
St. Clair109179
Kankakee87144
Kendall76919
Rock Island64624
Champaign6177
Madison56558
Boone42817
DeKalb3924
Sangamon34629
Jackson26810
Randolph2674
McLean21713
Peoria2128
Ogle2023
Stephenson1992
Macon19519
Clinton18117
Union1519
LaSalle14713
Whiteside13512
Iroquois1314
Coles12514
Unassigned1250
Out of IL1191
Warren1130
Jefferson10116
Knox970
Grundy952
Monroe9411
McDonough878
Lee791
Cass710
Tazewell714
Henry680
Williamson642
Pulaski510
Marion500
Jasper457
Macoupin452
Adams441
Perry420
Montgomery391
Vermilion391
Morgan351
Christian334
Jo Daviess320
Livingston322
Douglas260
Menard210
Fayette203
Ford201
Jersey201
Woodford192
Mason180
Washington180
Mercer170
Hancock160
Shelby161
Bureau151
Carroll142
Bond121
Franklin120
Piatt120
Schuyler120
Clark110
Crawford110
Fulton110
Moultrie110
Brown100
Cumberland100
Logan100
Wayne91
Alexander80
Henderson80
Effingham71
Johnson70
Massac70
Saline70
Greene50
Marshall50
De Witt40
Lawrence40
Richland30
Stark30
Clay20
Edwards20
Gallatin20
Hamilton20
Wabash20
White20
Calhoun10
Edgar10
Hardin10
Pike10
Pope10
Putnam10
Terre Haute
Clear
72° wxIcon
Hi: 75° Lo: 53°
Feels Like: 72°
Robinson
Scattered Clouds
74° wxIcon
Hi: 74° Lo: 53°
Feels Like: 74°
Indianapolis
Broken Clouds
70° wxIcon
Hi: 71° Lo: 50°
Feels Like: 70°
Rockville
Broken Clouds
69° wxIcon
Hi: 73° Lo: 51°
Feels Like: 69°
Casey
Scattered Clouds
73° wxIcon
Hi: 73° Lo: 53°
Feels Like: 73°
Brazil
Clear
72° wxIcon
Hi: 73° Lo: 52°
Feels Like: 72°
Marshall
Clear
72° wxIcon
Hi: 74° Lo: 52°
Feels Like: 72°
A wonderful Saturday with sunshine expected!
WTHI Planner
WTHI Temps
WTHI Radar

WTHI Events