국립 보건원은 현재 국내 인구의 1/3 이상이 결핵균 (tuberculosis, TB) 에 감염된 것으로 추정하며, 연간 약 34,000명 이상의 신규 결핵환자가 발생 한다고 합니다. 총 14만명 이상이 오늘도 결핵으로 인해 고통 받고 있습니다. 특히 건강한 20-30대의 젊은층에 신규환자가 집중되고 있으며 이는 무리한 다이어트와 과중한 스트레스로 인한 영향이 크다고 합니다. 한국 정부는 결핵을 법정 전염병으로 고지하여 이미 1960년 대 부터 결핵에 감염된 한국인에게 무료로 치료약과 백신을 공급하고 있습니다. 치료만 하면 거의 100% 완치가 되는 질병입니다.
세계적으로 결핵환자는 아프리카와 인도등의 저 개발 국가에 전체 결핵환자 (930만명) 중 90% 이상이 집중되어 있으며 AIDS에 감염된 환자들의 제일 사망원인이 바로 결핵으로 인한 합병증 입니다. 그러나 기존의 100년 이상 백신으로 사용된 BCG로는 예방이 되지 않는 수퍼 결핵균의 출현으로 현재 심각한 수준의 공중보건이 위협을 받고 있는 상황으로 새로운 백신의 개발이 시급한 실정 입니다.
마이크로소프트 (MS)의 창업자인 빌게이츠와 그의 아내인 멜린다 게이츠의 복지재단에서는 이런 상황을 심각히 받아들여 미국의 Aeras Global TB Vaccine Foundation (http://aeras.org) 에 400 million $ (4.8 조원)을 기증하여 전세계 결핵백신의 95% 이상을 생산, 아프리카와 인도등지의 저소득층에게 무료로 백신을 제공 한다고 합니다. 한국의 distributor를 통해서 Aeras의 최신 결핵백신이 공급 된다고 하니 한국과도 인연이 깊은 단체입니다.
전세계적으로 신종플루로 인해 한 명이 사망하는 동안 32명의 사람이 결핵으로 사망한다는 사실, 놀랍지 않습니까? 한국에서도 여전히 매년 400 명 이상이 결핵으로 인해 사망하는 것이 현실 입니다.
Transcript from: http://www.npr.org/templates/transcript/transcript.php?storyId=102384091
The World Health Organization says the data collected last year found 9.3 million cases - new cases - of tuberculosis. And the number of people who died from that disease is like the casualty list from some catastrophic war. New strains of TB are more resistant to available drugs than ever before, so scientists are reexamining a century-old vaccine to see if they can make it work better. NPR's Brenda Wilson reports.
BRENDA WILSON: In the pristine corridors of Aeras Global TB Vaccine Foundation in Rockville, Maryland, with its double-locked doors and self-contained water purification system, new TB vaccines are at various stages of development, set to be tested in people soon. Plant manager David MacCallum(ph) wants us to put on lab coats before we enter the area where the vaccines will be manufactured.
Mr. DAVID MACCALLUM (Plant Manager): So I'm going to ask you to don this garment here, 'cause we're going to go through the labs, and I'm going to ask you to wear safety glasses.
WILSON: That not only protects people from harm, it protects the vaccines from contamination. Aeras director Jerry Sadoff says the vaccines being developed here work on the same principle as vaccines have for hundreds of years.
Mr. JERRY SADOFF (Aeras Director): The basic idea of a vaccine is to fool the body into thinking it's infected so it can make an immune response and it's not really infected. And then it remembers that, so that later when it sees the real pathogen like TB or HIV or whatever, it recognizes that it's been infected before and it has a big immune response ready to go.
WILSON: But here at Aeras, Jerry Sadoff says modern science, molecular biology, immunology, and genetics is helping create a better TB vaccine using an existing TB vaccine called BCG and improving it.
Mr. SADOFF: We force the BCG to make a lot more of these pieces of itself we call antigens that come from all different parts of its life cycle so that it makes them all at once, so that we've made it into a super BCG, so to speak, telling the immune system that this is what I'm going to be like at all different stages of the TB lifecycle.
WILSON: The old BCG vaccine originated a hundred years ago when two French scientists isolated the TB bacilli in cows. Dr. Barry Bloom of the Harvard School of Public Health says that at the time, nearly a third of the population of Paris was dying of TB contracted from cow's milk.
Dr. BARRY BLOOM (Harvard School of Public Health): The experience in Paris was that bovine TB that people got by drinking milk was much more virulent in humans than TB that one caught from other patients. And as a small aside, that's what pasteurization has prevented in modern times. We heat milk and kill the bacillus.
WILSON: It took the French scientists 13 years of testing in rats, mice, and monkeys to turn the deadly cow bacillus into a form that was safe enough to test in humans. And then they gave it to one child whose mother had died of TB.
Dr. BLOOM: This child lived a long and healthy life, whereas someone who had a parent with TB at that time, about 30 percent would die of tuberculosis.
WILSON: The old BCG vaccine is still one of the most widely used vaccines in the world, but while it confers some protection on infants and children, it doesn't work very well in all populations. One strain provided as much as 85 percent protection in England and zero protection in India.
There's speculation that other bacteria closely related to TB and the environment and warm climates weaken the effectiveness of BCG. Some people may be more susceptible to tuberculosis for genetic reasons or because of poor nutrition. The list goes on. Jerry Sadoff at Aeras says they have a series of vaccines under development now that they are hoping will provide lifelong protection.
Mr. SADOFF: We have a regimen for infants and children so that we can protect infants from getting disease when they live in these very tight quarters where adults that have TB are coughing on them and spreading the disease. And then we think we'll have to have a booster regimen like you do for many other vaccines in the adolescent or young adult times.
WILSON: Human tests of Aeras vaccines are scheduled for sometime this year in South Africa, Kenya, India, and other countries with high levels of tuberculosis.
Brenda Wilson, NPR News.
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