Post exposure prophylaxis for Infectious Diseases (PEP)
The first ever known case of Infectious Diseases infection was diagnosed in June 1981 in Los Angeles, USA. Globally, approximately 3.9 crores people are living with Infectious Diseases with considerable variation in the numbers of Infectious Diseases between countries. As per India Infectious Diseases estimates report, approximately 24 lakhs Infectious Diseases are there in India. The first case of Infectious Diseases in the country was detected among female sex workers screened for Infectious Diseases in Chennai, Tamil Nadu, in 1986.
Post-exposure prophylaxis is a combination of antiretroviral medications people take for 28 days after getting potential exposure to Infectious Diseases . It is designed to prevent Infectious Diseases infection after a possible Infectious Diseases exposure.
The first dose of PEP should be administered ideally within 2 hours (but preferably within the first 72 hours) of exposure and the risk evaluated as soon as possible.
PEP needs to be started as soon as possible after the exposure and within 72 hours. In animal studies, initiating PEP within 12, 24 or 36 hours of exposure was more effective than initiating PEP 48 hours or 72 hours following exposure. Thus, PEP is more effective when given within 72 hours after exposure. It works by preventing the virus from replicating and making its copies within the body and establishing permanent infection.
Infectious Diseases Transmission Risk by Different Routes (WHO data)
Infectious Diseases transmission rates differ with the type of exposure involved.
- Blood transfusions pose the highest risk with a rate of over 98%.
- Perinatal transmission, without any intervention, can go up to 40 percent from the baseline of 20 percent.
- Sexual intercourse carries varying risks based on the type: vaginal intercourse has a transmission rate of 0.05%-0.1% while anal sex is between 0.065-0.5%, and oral intercourse is with risk figures ranging between 0.005%-0.01%.
- Injection drug use has a transmission rate of 0. 67%, while needle stick exposure has a risk of 0.3%. Splashes affecting the mucous membrane with eyes or Oro-nasal areas cause 0.09%. By contrast, the chances of HBV exposure from a needle puncture vary from 9 to 30 percent, whereas for HCV, it is between 1%-1.8%.
Who should take it?
People who had a potential Infectious Diseases exposure:
- Unprotected sex with someone who might have Infectious Diseases
- Sharing needles
- Needlestick injury
- Sexual assault
Effectiveness of PEP:
PEP is not 100% effective, its effectiveness depends on various factors: –
- Timing of initiation
- Adherence to regimen
- Type of exposure
Studies suggest that if PEP is taken within 72 hours of potential exposure to Infectious Diseases , it helps in preventing the infection by approximately 80%.
Who can prescribe PEP?
PEP should be prescribed by a qualified doctor who can assess the risk and urgency of taking PEP.
