HBV causes excess male births

A rogue economist says:

Sen claimed that there were some 100 million "missing women" in Asia. While the ratio of men to women in the West was nearly even, in countries like China, India, and Pakistan, there were far more men than women. Sen charged these cultures with gravely mistreating their young girls?perhaps by starving their daughters at the expense of their sons or not taking the girls to doctors when they should have. Although Sen didn't say so, there were other sinister possibilities. Were the missing women a result of selective abortions? Female infanticide? A forced export of prostitutes?

It turns out that half of these supposedly missing women can be explained by a side-effect of hepatitis B.