Quoting above messages:

“Thank you for the help. Your advice led me to the antirootkit software and then to the srosa.sys investigation. Google took me to this site: http://www.zonavirus.com/datos/descargas/95/elibagla.asp and to a small program called ElibaglA, which did the cleaning for me.
I’ve reinstalled Avast and Spybot and both work now.”

Thas how I did it. This program removed all items reported by AVG, so it seems every one of them was part of the infection.