Curious Bends – food prize, TB’s weakness, India’s big brother and more

1. World Food Prize goes to Sanjaya Rajaram 

“The 71-year-old veteran plant scientist has been declared the winner of the $250,000 World Food Prize this week. Born in Varanasi in India and now a citizen of Mexico, he has been chosen for his contribution to increasing global wheat production by more than 200 million tonnes in the years following the Green Revolution.” (2 min read)

2. Tuberculosis bacteria has a chink in its armour

With an increase in the number of antibiotic-resistant bacteria, the need to develop new ways to fight infection has never been more urgent. Now researchers at the Indian Institute of Science have found a new anti-microbial target in TB bacteria, and it holds potential for new drugs. (4 min read)

3. Now we know why drugs don’t work on pancreatic cancer

“The quirks of pancreatic cancer make it one of the most lethal. The survival period after diagnosis is only four to six months. The widely believed reason for this failure has been that in pancreatic cancer, the tissue that surrounds the tumour, called the stroma, blocks the delivery of chemotherapy drugs to the tumour. But new research has turned that logic on its head.” (3 min read)

+ The writer, Mohit Kumar Jolly, is a graduate student at the University of Rice. This week he is blogging from the Lindau Nobel Laureates meeting.

4. The biologist who played with animal poisons

Professor KS Krishnan, one of India’s top biologists, passed away earlier this year. “His fundamental impact was the ease with which he repeatedly linked his questions with the most innovative solutions. He was too smart to pursue science as a set of minor achievable goals. The exciting things he talked about were too broad to be limited to just one discipline. He was a man of science who loved molecules and molluscs in equal measure, researching the unexplored world of animal poisons, looking for that missing miracle cure for some of the most dreaded human diseases of the nervous system.” (3 min read)

5. India’s big brother is coming to Surat

Not the reality TV show, but the Orwellian character who watched over the action of the country’s citizens. Citizens of Surat, however, are celebrating. Their city will become the first to setup a network of closed-circuit cameras. The hope is that it will reduce crime, but past evidence on the use of such networks is not clear. Without proper laws in place to protect citizens’ privacy, India must debate surveillance before it is too late. (4 min read)

Chart of the week

An ageing population is going to be one of the greatest challenges of the 21st century, but solutions around the world differ wildly. Spot India and China in the chart below, and then hope that India’s health minister Harsh Vardhan will start acting rather than creating controversies. Those in the US can weep a little, too. Credit: 2013 health report by the OECD.

Screen Shot 2014-07-01 at 07.03.07

For more, follow the curators Mukunth and Akshat. Get in touch with us at curiousbends@gmail.com.

Chest X-rays are not effective at detecting TB infections

Enlarged microscopic image of TB-causing bacteria, Mycobacterium tuberculosis

When I immigrated to the UK as a student, I had to do something that I wasn’t expecting. I had to carry with me a recent chest X-ray. I thought this was completely unnecessary. Why should I be exposed to X-rays for no good reason?

Turned out that there was a reason. It was to stop the spread of tuberculosis (TB) in the UK. Immigrants from sub-Saharan African and the Indian subcontinent are more likely than other immigrants to be infected by TB.  The UK has seen TB cases increase continuously over the past 30 years. Between 1998 and 2009 the numbers rose by 50% to 9040 cases. Most of those affected are foreign-born people. TB infection rates in the UK today are as high as they were in the 1930s, and they are among the highest in any developed country.

The rise in number of cases is despite chest X-ray screening that immigrants have to undergo. That’s because of TB’s quirky ability to show up many years after the TB-causing bacteria infected a person. Researchers find that early detection makes it easier to treat TB, because more severe infections are becoming resistant to current treatments.

With an aim to improve detection rates, Onn Min Kon, a physician at Imperial College London, and colleagues report, in a paper just published in Thorax, that chest X-rays are actually not as effective at detecting TB. Instead, they suggest, the UK government should use an advanced test called interferon-gamma release assays (IGRA).

IGRA works on the principle that when the TB-causing bacteria are exposed to a set of chemicals, which are harmless to humans, it causes them to release a protein called interferon-gamma. If a patient who has been given these chemicals breathes out interferon-gamma, then he is infected by TB (the latent variety or not).

Although a previous consultation with the National Institute for Health and Clinical Excellence had recommended the use of IGRA, it had made that recommendation in combination with chest X-rays. What Dr Kon’s work finds that a more cost-effective, and still efficient, method would be to just use IGRA. It would also spare the patient from being exposed to X-rays!

This research is one among many other papers published in Thorax’s special issue dedicated to TB which coincides with the upcoming World TB day.  

Reference: Pareek, Bond, Shorey, Seneviratne, Guy, White, Lalvani & Min Kon, Community-based evaluation of immigrant tuberculosis screening using interferon γ release assays and tuberculin skin testing: observational study and economic analysis, Thorax 2013http://dx.doi.org/10.1136/thoraxjnl-2011-201542

Image from here.