VOA慢速英语2015 耐药结核病传播的可能性较小

AS IT IS 2015-07-02 Drug-Resistant¹ Tuberculosis² Less Likely to Spread 耐药结核病传播的可能性较小

The number of multi-drug-resistant tuberculosis cases is rising. Multi-drug-resistant TB results from a bacterium³ – a group of small living things that can cause disease. The bacterium is hard to kill because it has become resistant to two or more common antibiotics⁴.

But researchers have reported some good news: the multi-drug-resistant form of TB is less infectious than other forms of the disease among a patient’s close friends and family members.

In 2013, the World Health Organization reported almost 500,000 cases of multi-drug-resistant TB. Anti-microbial tuberculosis often infects patients who were treated earlier for TB or those infected with HIV, the virus that causes AIDS.

Often, these patients did not complete the drug treatment ordered by doctors, giving the bacterium time to develop defenses against the antibiotics.

Experts say treatment for multi-drug-resistant TB can take up to two years and require as many as six strong, less modern antibiotics. These antibiotics often have a higher death rate than today’s antibiotics because of the drugs’ toxicity⁵ – the harm they can cause to the body.

But British and Peruvian researchers are offering some hope. Their findings were published in the journal PLOS Medicine.

The researchers found that drug-resistant forms of TB have a lower “fitness” for spreading to people close to those infected with it. That means the disease does not spread as aggressively as non-drug-resistant TB.

Louis Grandjean works at Imperial College London. He led the study in Peru.

“In becoming drug-resistant, the bacteria undergo what it called a ‘fitness’ cost. So it’s able to survive in the environment of antibiotics, but it’s less able to jump from person to person and cause disease.”

For three years, the researchers followed more than 1,000 family members and friends of people with multi-drug-resistant tuberculosis. They also followed more than 2,300 contacts of patients with non-drug-resistant TB in Lima.

Thirty-five of the multi-drug-resistant contacts became sick during the study. Of those in contact with patients with non-drug-resistant TB, 114 of them became sick.

The researchers found that contacts of the multi-drug-resistant group were 44 percent less likely than the others to get sick with tuberculosis.

Yet Louis Grandjean says that does not make multi-drug-resistant TB any less of a threat.

“It’s still a huge problem, despite what we found in the study, which is encouraging and suggests that the tuberculosis program, which is working at full capacity to try to control multi-drug-resistant tuberculosis, is still a great problem.”

Given the seriousness of the threat, he says, the world cannot ease up on treatment efforts and guarding against the disease.

Words in This Story

antibiotics – n. drugs used to kill harmful bacteria

anti-microbial – adj. destroying or limiting the growth of very small organisms

fitness – n. the ability of an organism to survive

undergo – v. to experience

1 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。

2 tuberculosis   

n.结核病，肺结核

参考例句：

• People used to go to special health spring to recover from tuberculosis.人们常去温泉疗养胜地治疗肺结核。
• Tuberculosis is a curable disease.肺结核是一种可治愈的病。

3 bacterium   

n.(pl.)bacteria 细菌

参考例句：

• The bacterium possibly goes in the human body by the mouth.细菌可能通过口进入人体。
• A bacterium is identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。

4 antibiotics   

n.（用作复数）抗生素；（用作单数）抗生物质的研究；抗生素，抗菌素( antibiotic的名词复数 )

参考例句：

• the discovery of antibiotics in the 20th century 20世纪抗生素的发现
• The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。

5 toxicity   

n.毒性，毒力

参考例句：

• The hoarse grunt or squeal is characteristic of toxicity.嘶哑的哼声和叫声是中毒的特征。
• Dieldrin is related to aldrin,and its toxicity to earthworms is similar.狄氏剂与艾氏剂有关，对蚯蚓的毒性是相似的。