In some cases, co-infections may be insignificant, and have no additional effect on a person’s wellbeing. However, they can also be harmful, depending on how they interact within and with the body; this can affect the accuracy of diagnostic tests, and the efficacy of treatment. The harmful effects of chronic co-infections in association with HIV are well established (such as with tuberculosis or Hepatitis B and C); recent studies have focused on ways to allay these impediments. However, the outcomes of many acute co-infections are much less certain due to the challenges of studying naturally acquired infections. Therefore, co-infections matter when they interact with one another, and instead of simply expressing both sets of symptoms, the effects compound and new complications arise. This can occur from acute infections, but is much more likely to happen as a result of chronic infections that cause long term complications.