1.1.6 Prevention
1.1.6 Prevention
Prevention: avoid risk behaviors. Shots of gamma globulin (now hopefully safe) after a person has been stuck with a needle do not seem to work. There are no current HCV vaccines. With screening of the blood supply, the risk of HCV infection from a transfusion has dropped from 10% (1970’s) to less than 1%. (“Prevention, Diagnosis, and Management of Viral Hepatitis,” AMA)
1.1.6a When, and for how long, is a person able to spread the hepatitis C virus?
Eighty-five to ninety percent of all HCV carriers will have it for life, or until a cure is found. There is still a debate over whether people who have had a sustained viral response after treatment are cured, or if they are just in remission.
All carriers of HCV can transmit the disease to others via his or her blood. The disease may occur in the acute form and be followed by recovery, but the majority of the cases become chronic and cause symptoms for years.
A study at the Center for Disease Control and Prevention, Atlanta, suggests that HCV in dried blood may survive on environmental surfaces at room temperature at least 16 hours but not longer than 4 days. (www.hepatitisresources-calif.org/news Krawczynski, Kris, et al, Centers for Disease Control and Prevention, Environmental stability of hepatitis C virus (HCV): Viability of dried/stored HCV in chimpanzee infectivity studies. 11/25/2003)
1.1.6b How can the spread of hepatitis C be prevented?
People who have hepatitis C should remain aware that their blood and possibly other body fluids are potentially infective, even when the person carrying the virus is asymptomatic. Care should be taken to avoid blood exposure to others by sharing toothbrushes, razors, needles, etc. Infected people must not donate blood, plasma or semen, and should inform their dental or medical health providers so that proper precautions can be followed.
1.1.6c Cleaning up blood spills
A 10% bleach solution (soak for 30 minutes) should be used on all contaminated surfaces. There is no proof that this KILLS everything, but you can’t autoclave the world. There are also chemical disinfectants containing phenols and other very expensive ingredients, but for home use bleach is the best we have. Bleach can be very, very corrosive on some surfaces...so be careful what you slop it on. For cleaning up blood on the skin, use isopropyl (rubbing) alcohol.
Dispatch Hospital Cleanser Disinfectant with Bleach ( www.caltechind.com/dispatch/index.asp ) and Spartan Chemical’s HDQ NEUTRAL7 ( www.spartanchemical.com ) both claim to kill HCV.
From the hepc.bull Dec 1999, Issue 18:
“BLOOD SPILLS: DO YOU KNOW HOW TO SAFELY CLEAN UP A SPILL OF BLOOD OR BODY FLUID? THIS ARTICLE WILL TELL YOU HOW”, by Mark Bigham, MD, FRCPC, British Columbia Centre for Disease Control
Hepatitis C virus (HCV) is transmitted mainly by exposure to HCV-contaminated blood. HCV infection is not generally associated with exposure to other body fluids, such as saliva, urine, feces or vomit, but if HCV-contaminated blood is present in these or other body fluids, then the risk of infection will be greater. Therefore, it’s important to treat any environmental contamination of blood or body fluid as potentially infectious. The simple principles of cleaning and disinfecting, which are effective against HCV, are also very effective against other micro-organisms.
Viruses can only reproduce inside cells and HCV will not survive very long outside the human body (usually no more than a few hours). Survival of HCV in the environment is limited by such factors as lower temperature and dryness. HCV is also readily killed by standard household products, such as 5% household bleach or 70% isopropyl alcohol.
If you encounter a spill of blood or body fluid, the most important infection control principle is to avoid direct contact.
This is easily and effectively achieved by wearing rubber gloves—preferably single use, disposable vinyl gloves, or even household rubber gloves. Litter, such as broken glass should be picked up first. Try not to handle broken glass that could tear the gloves. Pieces of stiff cardboard or newspaper folded over can be used to pick up glass. When disposing of glass, wrap it in a newspaper before throwing it in the garbage bag, to protect municipal waste disposal workers from being cut when handling the bag.
Next, clean up the visible blood or body fluid with plain water and disposable paper towel. Using water will dilute the spill, reduce its infectivity, and facilitate wiping up the spill. Cleaning the visible spill will also remove organic matter that can reduce the effectiveness of disinfectants. The used paper towel can be put in a plastic bag (double bag if very wet and dripping) and disposed of in the regular household garbage.
A disinfectant should then be used. Regular 5.25% household bleach is an excellent disinfectant choice— it is inexpensive; has low toxicity and is not usually irritating to the skin; is fast acting; and is very effective not only against HCV, but also other blood-borne viruses (e.g., HIV, Hepatitis B virus), bacteria and fungi. It can be diluted with water to make a 1:10 to 1:100 bleach solution. The diluted solution should be prepared fresh, since bleach degrades over time when exposed to air or light. It can be wiped onto the surface with a towel and left to air dry, or poured onto the affected area and then wiped up with disposable paper towels after 10 minutes. An effective, alternative disinfectant for use on colour-sensitive fabrics or materials is 70% isopropyl alcohol, full strength, and applied in the same manner as described for bleach.
Gloves can then be carefully removed and disposed of in the regular household garbage along with the used paper towels. Reusable gloves can be rinsed in water and dipped or wiped in disinfectant and allowed to air dry. Finally, don’t forget to wash your hands.
1.1.6d What to do in case of an accidental needlestick
Because there is no effective neutralizing antibody or vaccine for preventing HCV transmission, HCV can be transmitted to health care workers through accidental needlesticks. In a study reported in the journal Clinical Infectious Diseases, after the clinical onset of acute hepatitis, two health care workers who had sustained accidental needlesticks were treated with interferon (total dose, similar to 300 mega units).
Neither individual developed chronic hepatitis. This finding raises the possibility that treatment with low-dose interferon following an accidental needlestick may be beneficial, even when it is started after the clinical onset of hepatitis. (“Early Therapy with Interferon for Acute Hepatitis C Acquired Through a Needlestick.” Clinical Infectious Diseases, May 1997;24(5):992-994.)
Another study showed 100% 2-year sustained viral response with alpha interferon monotherapy for acute hepatitis C. In a small study with seven patients, high-dose treatment for one year (5 mil daily for was 12 weeks, followed by 3 MIU 3-times weekly for 40 weeks. This represents a total alpha interferon dose of 780 MIU. The results were that all seven of the seven treated patients (100%) with acute HCV infection had a sustained viral response two years after completing therapy.
By contrast, only two of ten (20%) of those with chronic hepatitis C in the comparative arm achieved a sustained viral response. The difference was statistically significant (Digestive Disease Week 2000).
One health worker was treated successfully with short term therapy of IFN alpha plus ribavirin for 3 months. (Acta Gastroenterol Belg. 2005 Jan-Mar;68(1):104-6.)
1.1.7 Whom should I tell?
If you have hepatitis C, you are under no legal obligation to tell others. However, the law may change. Right now, it is up to you to decide whether to tell anyone of your hepatitis C status. Some people (and unfortunately some health care providers also) may have judgmental attitudes or unnecessarily exaggerated fears of infection.
People should carefully consider whom they inform, in the light of possible discrimination. How people might have caught the virus is not important. Those who have the hepatitis C virus are covered by anti-discrimination laws.
Recent cases where patients have been infected by physicians has raised the ethical issue of whether or not infected physicians should be banned form performing invasive procedures. So far nothing has been done in this respect (Milbank Q 1999;77(4):511-29) Infected physicians and invasive procedures: national policy and legal reality; Rev Med Virol 2000 Mar;10(2):75-78 Surgeons who test positive for hepatitis C should be transferred to low risk duties).
Surgeons infected with HCV in Germany are allowed to perform surgery with approval of a committee of experts which takes into account the individual situation, such as viral load. (Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz. 2004 Apr;47(4):369-78.)
1.1.8 Can you get hepatitis more than once?
Once you completely recover from hepatitis A or B you can’t get it again, although in some people the condition becomes chronic and can last their whole lives. But since there are at least five different viruses that cause hepatitis, you can get one of the others (though not D if you are immune to B). Becoming infected with B and C at the same time may actually cause a much more severe, dangerous case of hepatitis. A person who has recovered from a case of viral hepatitis could also develop hepatitis again due to other causes, such as alcohol or drugs.
If you have had hepatitis C and clear the virus, you can become infected with it again, or you can become co-infected with more than one genotype. Because there are so many different genotypes of hepatitis C, and because the virus mutates so rapidly, natural immunity is not developed. Studies have shown chimpanzees that have recovered from acute hepatitis C became sick again when re-exposed to the same strain of the virus.
Prev | Table of Contents |
Next |
1.1.5g Is HCV Anything Like HIV? |
Реклама: |
---|
|