Brazil has declared a six-month animal health emergency after several cases of avian flu (禽流感) were found in wild birds. Seven cases have been reported in Espirito Santo state, with another discovered in Rio de Janeiro state. The emergency declaration makes it easier for the government to now bring in measures to stop the highly infectious H5N1 virus from spreading.

Brazil is the world’s largest exporter of chicken meat, with annual sales of nearly $10bn. Authorities say the cases were found far away from Brazil’s main areas of production in the south of the country. However, outbreaks in commercial flocks elsewhere have sometimes been observed to follow the discovery of avian flu cases in wild birds. The finding of a case on a farm often causes the kill of a large number of birds—and can sometimes result in trade restrictions from other countries. The health emergency has been declared across the whole country for the next 180 days as a precaution (预防措施).

The world has been going through its worst ever outbreak of bird flu since October 2021, causing the deaths of more wild birds than ever before. Some mammals are also catching the disease. Scientists remain unsure why this outbreak is proving so much worse than others, but the World Organization for Animal Health (WOAH) has reported “fatal impacts on animal health and welfare”. The World Health Organization (WHO) says the further spread of the H5N1 virus will have to be monitored closely to see whether it is changing into a form which can spread among humans. Cases that do occur are the result of people coming into close contact with infected birds.

1.What’s the first paragraph mainly about?

A The current situation of avian flu.

B The benefits of emergency declaration.

C The declaration of animal health emergency.

D The background of Brazil animal health care.

解析：选C。C段落大意题。根据第一段内容可知，第一段首先介绍了巴西宣布进入动物卫生紧急状态，然后说明原因，最后说明此项宣布的好处，综合可知，选项C最符合文意。故选C。

2.What may be influenced by cases of avian flu?

A Brazil’s import of chicken meat.

B The survival of birds.

C Other commercial industries.

D Trade restriction from Brazil.

解析：选B。B细节理解题。根据第二段可知，巴西是鸡肉出口大国；在野生禽类中发现禽流感病例之后，在一些商业禽类群中也偶尔发现了禽流感爆发；在农场发现禽流感病例可能会导致大量鸟类被捕杀；有时禽流感爆发还会导致其他国家对巴西的贸易限制。故选B。

3.What can be learned from the last paragraph?

A The history of the bird flu.

B The reason of this outbreak.

C The degree of the bird flu damage.

D The way of monitoring the bird flu.

解析：选C。C细节理解题。根据最后一段可知，最后一段提到了自2021年来，世界正在经历有史以来最严重的禽流感，并未提及禽流感的历史；且第三句说明原因并未确定；根据“fatal impacts on animal health and welfare”可知这次禽流感的损害程度很致命；段落最后提到必须监测病毒，并未提及监测手段。故选C。

4.What’s the cause of human infection of avian flu according to the text?

A Taking the same food with infected birds.

B Eating meat from chickens infected with avian flu.

C Touch on the dead animal bodies.

D Close contact with infected birds.

解析：选D。D细节理解题。根据最后一段最后两句可知，人类发生禽流感的病例是人与受感染的禽类密切接触的结果。故选D。