Of course, yes! Most of the STIs for example syphilis, gonorrhea, and chlamydia can affect people more than once in their lifetime. Since there is no immunological protection from past infection, it is possible to get re-infected from the same or other STI. According to a study done by John Hopkins University, 1 out of 20 people get re-infected by the same STI within the same year. Why is re-infection common even if the treatment is simple and the success rate is high? This is mainly due to lack of patient compliance and inability to comply with proper precautions. Even after completion of a treatment regimen, it is vital to continue using protective barriers during sexual contact in all subsequent interactions. Precautions such as compulsory usage of protective barriers such as condoms, and avoiding unprotected sex with multiple partners is essential. If people do not take these precautionary measures seriously, then no doctor can prevent them from getting an infection. To prevent reinfection from STI, screening also plays a vital role. Screening is done to find people who may unknowingly transmit the infection to their partners being asymptomatic carriers themselves. Reinfection will not occur if both the partners get the treatment, provided that any sexual contact is limited between the couple. But if only one partner gets treated then the partner who has not received the treatment may re-infect the treated partner. However, there are STIs like hepatitis and HIV which cannot be eradicated completely and infection persists throughout a patient’s life. In these infections, the virus or other organisms will stay in the body forever and treatment only reduces the viral load instead of curing the infection.

Early testing is very important in diagnosing STI. But in some cases even after testing, people may get a negative result despite having all the symptoms of an STI. This can be due to various factors: The test result can be negative if the STI is having a window period. It is the time period between the person coming in contact with the organism till the organism shows itself in the sample. If people test the sample in this time period then the test result may come out as negative.

Sometimes, people may experience the symptoms of STI but it may not necessarily be a STI. Nonspecific organisms may also cause STI like symptoms. Nongonorhheal infection, nonchlamydial infections are such examples where people experience burning urination and pain during or after sexual intercourse. But after testing, the test result may reveal that you do not have a STI. In this case, other differential diagnoses must be taken into consideration.

If the sample is inadequate then the test result may also come out to be negative. This is called false negative when there is an actual infection but the tests say otherwise. If the same is taken to the lab after a long duration, or if the chemical used to test the sample is damaged, then the test result may not be accurate and may come out as negative.

Overall, there are many factors in which the test results may come out to be negative but the patient may still experience the symptoms of STI. In this case, it is better to treat the patient according to the symptoms. A false negative report is more dangerous than a false positive where the test shows positive even if the patient has no disease. As the famous saying in medicine says,"overtreatment is always better than under treatment".