TRANSMISSION OF BLOODBORNE PATHOGENS: HIV,HBV,HCV. Dr Daniel Kimani HIV Prevention Medical Transmission CDC, Kenya.

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1 TRANSMISSION OF BLOODBORNE PATHOGENS: HIV,HBV,HCV Dr Daniel Kimani HIV Prevention Medical Transmission CDC, Kenya.

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3 Nevada Hepatitis C Outbreak Tied to Las Vegas Clinic. Thousands Now At Risk for Hepatitis, HIV Date Published: Thursday, February 28th, 2008 Resource-rich country with good outbreak investigation-as recent as last year. What is the situation is resource-limited settings???

4 I long to accomplish a great and noble task but it is my chief duty to accomplish small tasks as if they were great and noble Helen Keller

5 Bloodborne Pathogens are micro-organisms that are present in human blood and cause diseases in humans. The common pathogens in healthcare settings include HIV, Hepatitis-B, Hepatitis-C, Hepatitis-D. Other organisms transmitted through blood include viruses such as CMV, HTLV-2, EBV, JCV, Spirochetes such as Syphilis and parasites such as malaria and babesiosis.

6 Transmission of Bloodborne Pathogens In addition to blood, other fluids may also present an infection risk: Synovial Fluid Semen Peritoneal Fluid Pericardial Fluid Cerebralspinal Fluid Bloody Body Fluids Pleural Fluid Amniotic Fluid Saliva in Dental Procedures Vaginal Secretions HIV or HBV Cultures Unfixed Tissue

7 Global burden of unsafe injection practices: WHO, 2004 estimates HBV - 21 million HCV - 2 million HIV/AIDS - 260, ,000 deaths Some of these are in healthcare workers Yet in SSA there are only 1 Doctor per 10,000 population

8 Frequency of Percutaneous Injury in Healthcare Personnel Based on CDC estimates, 384,325 (95% CI 311, ,922) percutaneous injuries are sustained by healthcare personnel in US hospitals annually Frequency of percutaneous injury varies by occupational group and healthcare setting In 2004 a study by the University of Nairobi documented 61 % needle stick injuries in health care workers over a three-month period. Needle recapping accounted for 46% of the injuries while 12% occurred in the process of sharps disposal.

9 Factors Influencing Occupational Risk of Bloodborne Virus Infection Prevalence of infection among patients Risk of infection transmission after a blood exposure Nature and frequency of blood exposures, for example splash to mucous membranes, cut, needle stick, skin contamination, quantity of blood involved and concentration of organism in the blood Stage of disease and viral load in source patient

10 Risk of Bloodborne Virus Transmission after Occupational Percutaneous Exposure Source HBV HBeAg + HBeAg - Risk %** % HCV 1.8% HIV 0.3% **Note high risk of HBV transmission

11 Viral Hepatitis - Historical Perspectives Infectious A E Enterically transmitted Viral hepatitis NANB Serum B D C F, G, TTV? other Parenterall y transmitted

12 Type of Hepatitis A B C D E Source of virus feces blood/ blood-derived body fluids blood/ blood-derived body fluids blood/ blood-derived body fluids feces Route of transmission fecal-oral percutaneous permucosal percutaneous permucosal percutaneous permucosal fecal-oral Chronic infection no yes yes yes no Prevention pre/postexposure immunization pre/postexposure immunization blood donor screening; risk behavior modification pre/postexposure immunization; risk behavior modification ensure safe drinking water

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14 Hepatitis B Modes of Transmission Hepatitis B can be transmitted in three ways: 1. Sexual transmission - Either homosexual or heterosexual 2. Parenteral - Such as an injury with needles and sharps - Injection drug use (IDU) - Blood Transfusion - Traditional practices-circumcision, uvulectomy etc 3. Perinatal - Virus can be transmitted from a mother to her infant during pregnancy

15 Hepatitis B - Clinical Features Incubation period: Average days Range days Clinical illness (jaundice): <5 yrs, <10% 5 yrs, 30%-50% Acute case-fatality rate: 0.5%-1% Chronic infection: <5 yrs, 30%-90% 5 yrs, 2%-10% Premature mortality from chronic liver disease: 15%-25%

16 Hepatitis B - Symptoms Only a small portion of acute Hepatitis B infections may be clinically recognized. Symptoms include: Anorexia or loss of appetite; Vague abdominal discomfort; Nausea and vomiting; Sometimes arthralgias and rash; Jaundice; Fever which may be absent or mild There are about 350 million chronic HBV carriers worldwide Kenya prevalence is about 7-10% HIV/HBV Co-infection is common-fuel each other Complications include cirrhosis and carcinoma

17 Treatment Interferon - for HBeAg +ve carriers with chronic active hepatitis. Response rate is 30 to 40%. alpha-interferon 2b (original) alpha-interferon 2a (newer, claims to be more efficacious and efficient) Lamivudine - a nucleoside analogue reverse transcriptase inhibitor. Well tolerated, most patients will respond favorably. However, tendency to relapse on cessation of treatment. Another problem is the rapid emergence of drug resistance. Adefovir less likely to develop resistance than Lamivudine and may be used to treat Lamivudine resistance HBV. However more expensive and toxic Entecavir most powerful antiviral known, similar to Adefovir Successful response to treatment will result in the disappearance of HBsAg, HBV-DNA, and seroconversion to HBeAg.

18 Prevention Vaccination - highly effective recombinant vaccines are now available. Vaccine can be given to those who are at increased risk of HBV infection such as health care workers. It is also given routinely to neonates as universal vaccination in many countries. Hepatitis B Immunoglobulin - HBIG may be used to protect persons who are exposed to hepatitis B. It is particular efficacious within 48 hours of the incident. It may also be given to neonates who are at increased risk of contracting hepatitis B i.e. whose mothers are HBsAg and HBeAg positive. Other measures - screening of blood donors, blood and body fluid precautions. The vaccine is offered in most private and a few public hospitals in Kenya including some pre-service training institutions. Considering high risk of transmission, lack of PEP and expensive and poor treatment outcomes for Hepatitis the best option for HCW is vaccination.

19 Hepatitis C Virus Most common chronic bloodborne infection in U.S. 3.9 million Americans (1.8%) have current or past infection with HCV 40% of chronic liver disease HCVrelated, leading to 8-10,000 deaths annually HCV-associated end-stage liver disease most common indication for liver transplants in U.S. adults Minimal data from Kenya

20 Risk Factors Associated with Transmission of HCV Transfusion or transplant from infected donor Injecting drug use Hemodialysis (yrs on treatment) Accidental injuries with needles/sharps Sexual/household exposure to anti-hcv-positive contact Multiple sex partners Birth to HCV-infected mother

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22 Hepatitis C - Clinical Features Incubation period: Average 6-7 wks Range 2-26 wks Clinical illness (jaundice): 30-40% (20-30%) Chronic hepatitis: 70% Persistent infection: % Immunity: No protective antibody response identified

23 Chronic Hepatitis C Infection The spectrum of chronic hepatitis C infection is essentially the same as chronic hepatitis B infection. All the manifestations of chronic hepatitis B infection may be seen, albeit with a lower frequency i.e. chronic persistent hepatitis, chronic active hepatitis, cirrhosis, and hepatocellular carcinoma.

24 Post exposure Prophylaxis for HCV Not recommended after exposure Immunoglobulin not effective No data on use of antivirals (e.g., interferon), which may be effective only with established infection No guidelines for therapy during acute infection When HCV infection identified early, refer to a specialist for proper management If HCV-positive source, test for anti-hcv and ALT 3-6 months after exposure Perform HCV-RNA at 4-6 weeks for earlier diagnosis of HCV infection, if symptoms appear or if ALT increases

25 HIV Within several weeks to several months after infection with the human immunodeficiency virus (HIV), many people develop an acute self-limiting flu-like illness lasting for a week or two. Infected people may then be free of clinical signs for Many months to years before clinical manifestations, Including opportunistic infections and constitutional and neurological symptoms appear. Disease progress from Stage-1 (asymptomatic) to Stage-4 (AIDS) Prevalence in Kenya is 7.1% (KAIS, 2007)-Highest in Nyanza at 15%, lowest in NEP at 1% Accounts for over 50% of bed occupancy

26 HIV Modes of Transmission Blood Contacts needle sticks and exposure of skin and mucous membranes, IDU, Blood Transfusion Sexual Contact exchange of vaginal secretions and semen Mother to Infant Scale up of HIV programs exposes HCW to more risks-diagnostic tests, monitoring tests, other procedures like LP, I&D etc.

27 Transmission Bloodborne Pathogens HIV No Vaccine Available Research continues toward the development of an AIDS vaccine. There is no vaccine available for the prevention of HIV infection.

28 Post exposure care I ve Been Stuck!! Promptly wash or flush the affected area and notify your supervisor! Currently treatment is recommended within 2 hours of exposure. Are SOPs or guidelines on first aid and PEP available?

29 How soon should one be evaluated? Promptly! You need to be evaluated as soon as possible after the exposure so that the severity of the injury can be assessed. Serious exposures will require the initiation of post exposure ARVs that are believed to be most effective when given within a few hours of the exposure. IMPORTANCE: PEP availability even in the remotest facility!

30 Preventing Transmission of Bloodborne Viruses in Healthcare Settings Promote hepatitis B vaccination Treat all blood as potentially infectious Use barriers to prevent blood contact Prevent percutaneous injuries by use of safety-engineered devices and use of correct technique Safely dispose of sharps and bloodcontaminated materials Offer post exposure prophylaxis (PEP) to all health care workers Quality assured screening of blood for transmission

31 Exposure Control Program Hospital IPC Committee A Written Plan Identifying Those at Risk Identify Training needs Offering Hep. B Immunizations Preventing Exposures Evaluating & Treating Exposures Properly Disposing of Waste

32 Employer Responsibilities Include Implementing a written plan. Enforcing good work practices that include disinfecting surfaces, following universal precautions, and proper waste disposal. Controlling exposures through the use of safer needle devices safety boxes, bio-safety cabinets, needleless IV systems, and self-sheathing needles. Training employees initially and through annual updates. Providing Personal Protective Equipment (PPE): gloves, gowns/aprons, eye protection (i.e., goggles, faceshields, side shields) and surgical mask Identifying hazards by proper labeling of: incubators, freezers and centrifuges Managing medical wastes PEP and care for occupational exposure Surveillance system for occupational injury

33 Individual Responsibilities Your Actions are key to good exposure control. These include: Attending training to update knowledge. Complying with Infection Prevention and Control Plan. Segregating medical waste properly. Properly selecting, wearing, removing, and disposing of Personal Protective Equipment (PPE). Support for fellow injured health workers-stigma reduction Keeping pace with technology!

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35 Segregating Medical Waste

36 Other Issues Sharps containers must be changed frequently enough so that they never become overfilled. To reduce the potential of injury due to an overfilled container, replace the sharps container when it is ¾full.

37 Prevention of Medical Transmission of Bloodborne pathogens in Kenya Injection Safety Program HCW training on safer practices Strengthening of logistics and procurement system for IS commodities Waste management systems support Behavior change communication and advocacy to reduce unnecessary jabs

38 Blood Safety Program Nationally coordinated blood service Selection of safer blood donors Quality processing and testing for transfusion transmissible infections (HIV, HBV, HCV, Syphilis) Appropriate blood use in facilities to avoid unnecessary transfusions

39 Conclusion Healthcare workers are at risk for occupational exposure to Bloodborne Pathogens. Exposure Control Plan that outlines the steps necessary to reduce infection risk should be in place in all facilities. When accidents occur, prompt medical attention is necessary. PEP should be accessible to all health care workers. Hepatitis B vaccination should be available to all health care workers Prevention is the key!!

40 THE GOOD WE DO TODAY BECOMES THE HAPPINESS OF TOMORROW WILLIAMS JAMES AHSANTENI!