This week I helped to launch a new all-party parliamentary group which I am co-chairing on the growing problem of global tuberculosis. There are already groups on malaria and AIDS, but TB was missing.
Yet TB kills nearly 2 million people a year worldwide, or 5,000 a day - in spite of the fact that it is a curable disease, treatment costs only a few pounds, and all but the most chronically affected need not even be admitted to hospital.
I take a close interest in these issues and visited Kenya last autumn to see the problem for myself. But this isn't just a personal concern. Along with climate change, international development is one of the issues about which I get most correspondence from my constituents.
In the last few days, I have received dozens of record sleeves urging me to "get on record" to declare my support for the target set at the G8 Gleneagles summit to make AIDS treatment universally available by 2010 - and I have done so without hesitation.
Sometimes people ask me whether our aid programmes can really be effective. Certainly poverty, malnutrition and minimal access to healthcare lies at the heart of pandemics in the developing world. Strengthening fragile economies, not least through free and fair trade, must be our ultimate goal.
But the immediate need to save lives remains, and our actions can make a difference. One expert at the Commons meeting pointed out that India's TB programme has saved 55,000 lives a year.
Another speaker, Winstone Zulu, spoke movingly about his life in Zambia, where the male life expectancy is 37. At 42, he is considered an old man. He contracted TB when he was younger. But he is alive while his brothers died. The reason? He was lucky enough to be given the drugs to cure him.