That HF album is more different than others. Has more powerful and darker sound, more modern Power metal and some songs sounds more to Hard Rock for example "I Refuse" (guitars here sounds like AC/DC) or good opener "Patient Zero". Here are many experiments with instruments lines. I think that this is why many HF fans do not like this album. Many fans just rejected the album because the mascot Hector was not on cover. Why judge the book due to the cover? This CD has many really good songs like the singl "One more time", great headbanger "B.Y.H" (Bang Your Head), my one of favorites here fast "The Outlow" or "Dia De Los Muertos", "666 - Enemy Whitin" I like pretty much too. But others are good, actually no songs are bad here. Ballad "Sand Me a Sign" is not the greatest in HF discography but worthy to heard. "Let's Get It On" is like American rocker song with good moments. "Immortalized" and "Redemption" are songs with big choruses for HF typical.
conclusion: Infected really is not the best from Hammerfall discography but worth to listen. It is very good album with many experiments so a large fans of old Hammerfall sound can be very disappointed but in my opinion it is something new and not a really bad thing. For those who like Hard Rock and modern Power Metal is Infected recommended from me. But I almost can hear cries of HF fans that like predecessors from 90s and early 21th century. Guys be cool, that is just one album of Hammerfalls fantastic career and as I said not bad at all. 7,5/10 = 4,5/6 stars. Because I could not give a half star then for the amazing Joacims voice here and because I like them a lot. I am giving to Infected 5 stars with one smaller than others.