During what period? According to Froome they told him it was not possible to determine how long it has been in his body.
I don't have the link, but Froome is on record giving a general time period during which he probably contracted the disease, and it was well after he turned pro. He's never claimed he had it long before he started riding.
No it wasn't. Until halfway through the Dauphiné in 2012 he was as bad as ever in the first half of the season.
Because he was sick. He had a chest infection. He had symptoms that would be perfectly unremarkable for someone with no history of schisto. Also, he was diagnosed in March 2012 with typhoid and blastocytosis (see below). Those are at least as likely a cause of poor performance as schisto.
I rechecked my original post
on the timeline.
According to the article discussed there, Froome actually had five
, not four treatments. The first was in October or soon after in 2010. (Edit: He was given PZQ over four days. The longer the period over which the drug is given, the more effective the treatment is. This makes it even more unlikely that this first treatment wouldn't cure the disease). The second was in June 2011. That is closer to the Vuelta that year, but it’s still a stretch to say that it could account for the big change in a few weeks between Poland and Spain, particularly when he was given a third treatment that November. If he had claimed that the second treatment cured him completely, he would have at least a little better case that maybe his Hb levels were still recovering at Poland, but by his own account, that treatment did not cure him.
He had a fourth treatment in March 2012, when he was diagnosed with other diseases. Then he underwent yet another round of tests in 2013—long after his early 2012 performances were over, and he had experienced a continuous string of strong performances on the bike—when he was given a fifth treatment with PZQ.
So again, the timeline doesn’t correlate with his performances. His first treatment in the fall of 2010 was not followed by a noticeably better performance for most of 2011. Even if that treatment did not fully cure him of the disease, it should have greatly reduced his worm burden and resulted in a major improvement in performance, if that was in fact what had been hindering him before. His second treatment in June 2011 was not followed by any performance benefit in Poland. He did have his breakout in the Vuelta, but then a couple of months later he was told he still wasn’t cured and needed another treatment. To the marvel of the medical profession, even that third treatment wasn’t enough, so he had a fourth the following spring. That was correlated with a return to his Vuelta performance, but he has said that he was diagnosed with other diseases and was treated for those, too. Then he rode very well in both the Tour that year and the Vuelta, considering it was his second consecutive GT. He rode very well all spring in 2013 and dominated the TDF, yet he was diagnosed yet again with disease and treated during that period.
So Froome's claim is that he was not fully cured of schisto until some time in 2013 when he had the fifth treatment. The implication is that at any time up to then, any poor performance of his could be attributed to the disease. But from the 2011 Vuelta through 2013, he never had a poor performance, except in the spring of 2012, when he was reported to have other serious health problems. Except for that one period, which can be very adequately explained, he was fine after the 2011 Vuelta.
Moreover, even if you want to give him the benefit of the doubt, and argue that his poor performance in early 2012 was the result of the schisto, why did this never happen before or since? In all the years he had schisto prior to the 2011 Vuelta, he was not up and down. He was consistently at a lower level.
Do you want to argue that once he started getting treatments, he had a temporary remission? But he had no improvement in performance after his first treatment in 2010, and it seems he got worse after his third treatment in 2011. Maybe that was because those occurred at the end of the season, and the benefits did not extend to the following racing season. But why would that be? After any treatment, the worm burden is going to decrease, which means the amount of eggs produced over time will decrease. This is not a temporary benefit. Even with the lower worm burden, there may still be a net accumulation of eggs, but it can't be worse than it was before the treatment. A treatment doesn't reduce the egg burden. It slows down the increase in this burden, and this effect is permanent.
Moreover, after his fourth treatment in 2012, the remission wasn't temporary, it was permanent, performance wise. Yet he was still diagnosed with schisto the following year and treated again.