year. The primary immunization program may be repeated, if reinfection or relapse occurs. Side effects Common side effects include pain, redness and swelling or hardening of the tissues at the injection site. Systemic vaccination reactions commonly include fatigue, flu-like symptoms, a raised temperature between , shivering, headache, dizziness, nausea and a swelling of the inguinal lymph nodes. Symptoms usually subside within days after injection and are less pronounced or absent at subsequent injections. Contraindications Gynatren is contraindicated in patients with a history of allergic reaction to the bacterial antigens or phenol contained in the vaccine. Further contraindications are acute fever, active tuberculosis, severe hematopoietic disorders, decompensated cardiac or renal insufficiency, autoimmune and immunoproliferative diseases. Gynevac is additionally contraindicated in arthritides affecting several joints, under immunosuppressive- or radiotherapy. Pregnancy Lactobacillus vaccines are not contraindicated during pregnancy and breastfeeding. Both Gynatren and Gynevac may be prescribed during pregnancy upon careful individual consideration of the potential risks and benefits. Lázár reported vaccinating 3457 pregnant patients with Gynevac between 1976 and 1982, usually starting the vaccination schedule at the first prenatal care visit, and has not observed any impairment of pregnancy or teratogenic effect in association to the lactobacillus vaccine. Rüttgers made similar observations about Gynatren when administered in the second trimester. Mechanism of action The mechanism of action of lactobacillus vaccines is far from being completely understood. At least three theories have been proposed. The most commonly accepted one, as formulated by Påhlson and Larsson, suggests that the vaccine breaks the immune tolerance of the host and makes it possible for the immune defense to attack aberrant, "ecologically wrong" lactobacilli and create an environment for beneficial strains to become dominant. Rüttgers on the other hand described SolcoTrichovac as an anti-adhesive vaccine, suggesting that the induced antibodies and perhaps other mechanisms inhibit the adhesion of microbes to epithelial cells in a largely nonspecific manner. A third hypothesis, advanced by Goisis among others, involves the possibility of an immunomodulation resulting in tolerance, rather than defense against the bacterial antigens used in the vaccine. Multiple authors have proposed cellular immunological phenomena as the primary mediators of protective effect of lactobacillus vaccines. Studies into cellular immunity are technically challenging in humans owing to the difficulty of sampling lymphoid tissues as opposed to secretions, and none has been performed so far on lactobacillus vaccines. A number of studies have been published on the humoral responses to primary and