吸血昆虫引发新型艾滋病 美洲成重灾区

Experts have dubbed it the “new AIDS of the Americas.”

A parasitic infection called Chagas Disease has similarities to the early spread of HIV, according to research published recently in the journal PLoS Neglected Tropical Diseases.

Like AIDS, Chagas is hard to detect and has a long incubation period before symptoms emerge, the study said, according to the New York Times.

As many as 8 million people are infected in the Western Hemisphere, mainly in Bolivia, Mexico, Colombia and Central America, as well as some 30,000 people in the US, the newspaper reported. Chagas infects people in areas of poverty, and most US cases are found in immigrants.

Because Chagas is often left untreated, it spreads easily, either genetically or through blood transfusion. If caught early, it can be treated with intense medication, but the drugs are scarce in poor countries and very little money is invested in searching for new treatments, the paper said.

Chagas is usually transmitted from the bite of blood-sucking insects that release a parasite called Trypanosoma cruzi into the victim’s bloodstream. The parasite can eventually make its way to the heart, where it can live and multiply.

Infections often stay dormant for years, and then emerge as heart arrhythmias and heart failure. About a quarter of victims develop enlarged heart or intestines that can lead to sudden death if they burst, according to the Centers for Disease Control and Prevention.

New research suggests Chagas may have led to the death of Charles Darwin — one of the great medical mysteries.

Researchers from the University of Maryland School of Medicine believe Darwin suffered from three different illnesses, including a Chagas infection contracted on a voyage to the Andes in South America, the Wall Street Journal reported earlier this month.

Darwin wrote in his diary that he was bitten by a “great wingless black bug” during the trip in 1835. He died 47 years later of heart failure.

专家将其称为“美洲的新艾滋病”。

根据《PLoS被忽视的热带疾病》期刊近日发布的研究称，这种名为“查加斯病”的寄生虫传染疾病和艾滋病早期的传播过程具有相似性。

根据《纽约时报》，该研究称，查加斯病就像艾滋病一样难以觉察，而且在出现症状前有一段长时间的潜伏期。

据《纽约时报》的报道，在西半球已有800万人感染了这一疾病，患病者主要分布在玻利维亚、墨西哥、哥伦比亚和美洲中部，在美国也有3万人感染此病。查加斯病在贫民区的人群中间传染，许多美国患者都是外来移民。

据报纸的报道，因为查加斯病常常得不到治疗，因此它很容易就通过遗传或输血散播开来。如果在疾病早期发现，可采用密集药物治疗方法，但穷国的药品很稀缺，在寻求新疗法上投资也很少。

查加斯病通常是通过吸血昆虫的叮咬、将被称为克氏锥虫的寄生虫输入受害者血液中进行传播。这种寄生虫最后会到达心脏，在那里生存和繁殖。

根据美国疾病控制与预防中心，这种传染病通常会潜伏数年，然后以心律失常和心脏衰竭的形式发作。约有四分之一的受害者会发展成心脏或肠道扩大，如果发作可能导致猝死。

新研究显示，查加斯病可能是查尔斯•达尔文的死因——达尔文的死是史上最大的一个医学之谜。

根据《华尔街日报》本月早些时候的报道，马里兰大学医学院的研究人员认为，达尔文死前患有三种不同的疾病，包括去往南美安第斯山脉航海旅途中染上的查加斯病。

达尔文在他的日记中写道，1835年他在旅途中被一只“巨大的没有翅膀的黑色昆虫”咬了。47年后他因为心脏衰竭而死。