Bird Flu infects more in China

A Chinese policeman wears a mask as he guards access to a wholesale market where authorities are culling poultry after the new bird flu strain was detected in pigeons being sold for meat in Shanghai, China, April 5, 2013.

China announced a sixth death from a new bird flu strain Friday, while authorities carried out the slaughter of all poultry at a Shanghai market where the virus was detected in pigeons being sold for meat.

Read more: Two more bird flu deaths reported prompting Shanghai to slaughter poultry supply

Prepared ducks are hung to be cooked at a restaurant in Shanghai, China, April 5, 2013.

Workers in protective clothing move bags out from a wholesale market during a culling operation as authorities detected the new bird flu strain in pigeons being sold for meat at the market in Shanghai, April 5, 2013.

Free-range chickens are seen in Shanghai, China, April 5, 2013.

A vender leans on a cage at a poultry market in Shanghai, China, April 5, 2013.

Chickens are sold at a poultry market in Shanghai, China, April 5, 2013.

Workers in protective clothing move bags out from a wholesale market during a culling operation as authorities detected a new bird flu strain in pigeons being sold for meat at the market in Shanghai, China, April 5, 2013.

Caged chickens are sold at a poultry market in Shanghai, China, April 5, 2013.

A vender waits for the customers at a poultry market in Shanghai, China, April 5, 2013.

Workers in protective clothing chat during a culling operation as authorities detected the new bird flu strain in pigeons being sold for meat at a wholesale market in Shanghai, China, April 5, 2013.

Chickens are sold at a market in Shanghai, China, April 4, 2013.

A middle-aged man who transported poultry for a living has died from a new strain of bird flu in Shanghai, the fourth death among 11 confirmed cases in China, the government and state media reported Thursday.

A woman feeds ducks while her boyfriend takes photos at an amusement park in Beijing, China, April 3, 2013.

Scientists taking a first look at the genetics of the bird flu strain said Wednesday the virus could be harder to track than its better-known cousin H5N1 because it might be able to spread silently among poultry without notice. The bird virus also seems to have adapted to be able to be able to sicken mammals like pigs.

A worker arranges containers of chickens at a wholesale market in Shanghai, China, April 4, 2013.

Guidelines issued Wednesday by the national health agency identify butchers, breeders and sellers of poultry, and those in the meat processing industry as at higher risk.

A worker vaccinates a chicken at a chicken farm in Shanghai, China, April 3, 2013.

A woman and her daughter are frightened while ducks approach for food at an amusement park in Beijing, China, April 3, 2013.

A duck stands near a warning sign at an amusement park in Beijing, China, April 3, 2013.

A worker spays disinfectant on chicken cages at a wholesale market in Shanghai, China, April 4, 2013.

Chickens are placed in containers at a wholesale market in Shanghai, April 3, 2013.

Workers unload chickens from a container at a wholesale market in Shanghai, China, April 3, 2013.

A worker unloads a chicken from a container at a wholesale market in Shanghai, China, April 3, 2013.

A worker spays disinfectant on chicken cages at a wholesale market on in Shanghai, China, April 3, 2013.

A vender stands near bird cages at a chicken wholesale market in Shanghai, China, April 2, 2013.

A vender holds a chicken at a wholesale market in Shanghai, China, April 2, 2013.

Workers unload chicken containers from a truck at a wholesale market in Shanghai, China, April 3, 2013.

Ducks swim near a warning sign at an amusement park in Beijing, China, April 3, 2013.

A worker unloads a chicken from a container at a wholesale market in Shanghai, China, April 3, 2013.

A worker spays disinfectant on chicken cages at a wholesale market in Shanghai, China, April 2, 2013.

Ducks are fed by two tourists at an amusement park in Beijing, China, April 3, 2013.

A worker unloads a chicken from a container at a wholesale market in Shanghai, China, April 3, 2013.

A worker spays disinfectant on chicken cages at a wholesale market in Shanghai, China, April 3, 2013.

A worker catches a live chicken at a poultry market in Shanghai, China on Friday, April 5, 2013. China announced a sixth death from the new bird flu H7N9 strain Friday, while authorities in Shanghai halted the sale of live fowl and slaughtered all poultry at a market where the virus was detected in pigeons being sold for meat. The first cases were announced Sunday. (AP Photo)

A vender waits for the customers at a poultry market in Shanghai, China on Friday, April 5, 2013. China announced Friday a sixth death from a new bird flu strain while authorities carried out the slaughter of all poultry at a Shanghai market where the virus was detected in pigeons being sold for meat. (AP Photo/Eugene Hoshiko)