Finally, animals might effectively self-medicate, either prophylactically or therapeutically. In mice models, Favipiravir has been shown to be beneficial both therapeutically and prophylactically. Neonatal infection can be prophylactically treated with antibiotics. Surgery is a frequent risk factor for infection and a physician may prescribe antibiotics prophylactically. Methyl 5-benzoyl-2-benzimidazole was 100% efficacious when fed prophylactically to turkey poults. Cefazolin can be used prophylactically against perinatal Group B streptococcal infection (GBS). As it acts more specifically than polyclonal antibodies it is also used prophylactically in transplantations. Taken before symptoms appear, it may prevent disease in about three-quarters of people treated prophylactically. Passive transfer is used prophylactically in the case of immunodeficiency diseases, such as hypogammaglobulinemia. In Mexico, this is the treatment used prophylactically in newborns. Equally, orthoses are sometimes used prophylactically or to optimise performance in sport. These defences can be employed either prophylactically or on demand. Such behaviours can be employed either prophylactically, or actively, upon demand. However, it is not to be used prophylactically.