When the body is fighting off infection, it will lower red blood cell count so that the infection doesn't have a transporter (hemoglobin) to make the infection worse. So if you have bacteria, the last thing you want to do right now is build up your blood. You have to kill off the infection first.
If you don't want to take the Antibiotics
(I wouldn't want to, yuck) please consider taking something like Parastroy or Clarkia
, both designed to kill micro-organisms and larger worm type parasites.
Once the infestation is gone, your blood cell count should rise as long as your diet is good.