Остановка Гепатит С1.1.0 HCV and Blood Transfusion
1.1.0 HCV and blood transfusions
Anyone who received a blood transfusion or a blood product before 1992 is considered to be in a high risk group. Blood banks began screening donors for certain markers as early as 1986, but contaminated blood still found its way through to patients. In May 1990, screening tests for the hepatitis C virus came into use, and the risk is now thought to be 1 in 3,300 or 0.12% for the typical recipient of a transfusion. A typical recipient is one who does not have other conditions that would make it more likely for them to catch the virus (like HIV infection). - California at Berkeley Wellness Letter, May 1993 (see Appendix E: History of Blood Safety).
HCV acquired through blood transfusion tends to be more severe than through other modes of transmission.
1.1.1 HCV and intravenous drug use
Investigators at Johns Hopkins report that injection drug users are at high risk for contracting hepatitis B and C, and that many contract
hepatitis B or C within the first year of IV drug use.
Dr. David Vlahov and colleagues studied 716 volunteers who had been injecting for six
years or less. Seventy-seven percent of them were infected with HCV and 65.7% were infected with HBV. Roughly 20% were HIV-positive. Hepatitis C
was more prevalent among those who reported injection drug use for less than four months than among those who reported injecting drugs for 9 to
12 months. (Am J Pub Health 1996; 86:642-646.)
Studies in British Columbia (1999) show that 90% of the male prison population is infected
with HCV.
1.1.2 HCV and IV immunoglobulin (gammagard/polygam/factor D)
Contaminated batches of Gammagard and Polygam, drugs used in intravenous immunoglobulin therapy, may have caused thousands across the U.S. to
contract the hepatitis C virus. Many of those infected by Gammagard were children. Gammagard is primarily used to boost a patient’s immune
system. Many women in Ireland were infected through the use of contaminated Factor D after childbirth.
Patients who received immunoglobulin
therapy should contact their doctor immediately to have liver function tests performed.
1.1.3 Neonatal transfer of HCV
The following is from the HepCBC pamphlet HCV & Pregnancy.
Reducing the Risk of Transmission During and After Pregnancy.
A woman living with Hep C who wishes to become pregnant may be worried about the health of her baby. The chance of the virus being transmitted to the baby is 0-10%, but higher in persons who have HIV or use IV drugs. If a mother also has AIDS, the chances can increase up to 36 in 100. The risk may be even greater in mothers who are infected with both Hep B and Hep C.
Transmission to the baby can happen before or during birth.
Present information shows that transmission may be slightly more likely in infants born to mothers with genotype 1.
Most doctors and midwives will be helpful and supportive to a woman with Hep C who wants a child. Pregnancy with Hep C is not officially discouraged.
A woman may wish to take treatment for hepatitis C before becoming pregnant. She MUST wait at least 6 months after stopping treatment before getting pregnant, to avoid birth defects. Infected men on treatment should use birth control during, and for at least 6 months after treatment for the same reason.
Having a Caesarian section does not usually reduce the risk of transmission. However, it is possible that if a woman has an acute case of Hep C or is co-infected with HIV, there is more of a risk of her baby being infected.
Viral Load and Mother-to-Baby Transmission
Viral load is the amount of Hep C in the blood. If a woman with Hep C has low viral load (less than 1 million copies/mL), it is less likely that the virus will be passed to her baby than if she has high viral load, but there is still a chance that Hep C will be transmitted. If the mother has no virus, the baby will not be infected.
It looks like a female baby is twice as likely to be infected as a male baby.
(www.medicalpost.com/mpcontent/article.jsp?content=200601151815362940 January 17, 2006 Volume 42 Issue 02)
Breastfeeding
It is not yet known whether the breast milk of a woman with Hep C contains enough virus to infect a baby during breast feeding. Generally, women with Hep C are not advised to avoid breast feeding. No studies have documented transmission of Hep C infection to infants by breast-feeding. One study showed breast-fed infants were slightly less likely to have HCV. Mothers should not breastfeed when their nipples are cracked or bleeding, just in case.
A European study enrolling 1,479 mother-and-child pairs, and a US study which followed 244 infants born to HCV+ mothers, both published in the Journal of Infectious Diseases concluded that breastfeeding is safe.
(www.medicalpost.com/mpcontent/article.jsp?content=200601151815362940 January 17, 2006 Volume 42 Issue 02)
Children with Hep C (See also 2.8.0 How Does HCV Affect Children?)
In children, viral infection is usually silent, although children as young as 8 years old can become quite ill from HCV.
Children are less likely than adults to have symptoms of infection with Hepatitis C, and thus may be able to transmit the virus unknowingly.
Having hepatitis C does not seem to affect a child’s growth.
All children, with or without hepatitis C, should be taught proper hygiene.
Children and Advanced Liver Disease
Chronic hepatitis C eventually causes cirrhosis or cancer. However, it can take 10 to 20 years or more before cirrhosis may occur. Liver cancer rarely occurs in children.
Treatment in Children (Also see 2.7.1)
The AASLD recommends:
- Diagnosis, testing, and liver biopsy of children thought to have HCV.
- Because of the high spontaneous clearance rate during the first year of life, children of HCV-infected mothers should be tested at 18 months or later.
- Healthy children with HCV ages 3-17 may be given interferon alpha-2b and ribavirin by specialists in treating children
- Children under the age of 3 should not be treated.
There are still many questions about Hepatitis C in children. More studies are necessary to learn more about how the disease progresses and about different treatments.
Talking to Health Care Workers
Doctors and midwives can be helpful and supportive to a woman with Hep C who wants a child. It can be very hard for a woman with Hep C to tell her health care workers she is pregnant or wants to be, if she suspects they will try to change her mind. Health Care workers with experience in helping women who have Hep C are likely to be the best informed and most supportive.
1.1.4 Other means of HCV transmission
Like hepatitis B, hepatitis C is spread through exposure to blood from an infected person, such as through a blood transfusion or sharing needles. There is no evidence that the hepatitis C virus can be transmitted by casual contact, through foods or by coughing or sneezing.
1.1.4a Sexual transmission
Is HCV transmitted sexually? The answer is not as clear as we would like. Transmission in monogamous, heterosexual couples is considered to be 3% or less. There have been outbreaks of HCV in mostly HIV-infected males who engage in homosexual sex (MSM or Men who have Sex with Men) in Europe, but not in the US.
There was an article in the May 2007 HIV Medicine that reported 352 cases of HCV acquired in the previous 3 years in MSM examined between 2002 and 2006 a 20% increase during that period. Another study in the May 11, 2007 issue of AIDS reported 111 such MSM cases, and investigated to see if the virus strains were related. 7 clusters were identified, all within the HIV population. The HCV was associated with sexual transmission risk factors rather than IVDU. Risk factors were the number of sex partners, risky sexual practices, sharing of drugs nasally or anally, and group sex, which was the best predictor of HCV infection, especially when combined with high-risk practices.
In the US study, the only predictor of HIV/HCV co-infection was IVDU. A report in the June 1, 2007 Journal of Infectious Diseases concluded, “Our results are consistent with prior research indicating that sexual contact plays little role in HCV transmission.” ( www.hivandhepatitis.com/hiv_hcv_co_inf/2007/050107_a.html )
Practicing safer sex is always a good idea for people with multiple partners. People who engage in high-risk sexual behaviour have a greater risk of contracting STDs which can cause open sores and lesions. Open sores and lesions mean a greater risk of blood to blood contact and a higher risk of contracting hepatitis C. If you have herpes, you are at a greater risk of catching hepatitis C. It might be possible that HCV piggybacks on the genital herpes virus through genital lesions. If you have multiple partners, use condoms. People with acute HCV, or with compromised immune systems, should be more careful as these conditions can raise the level of virus in the bloodstream, and can mean a greater risk of infection. Sex during the menstrual period should be avoided, because of the blood in menstrual fluid.
A report from Health Canada, “Hepatitis C Prevention and Control: A Public Health Consensus,” June 1999, p.6, recommends that:
- People with multiple partners should practice safer sex.
- Longstanding sexual partners do not need to change sexual practices if one of them is found to be
infected with hepatitis C
“Hepatitis C virus is linked with existing hepatitis B virus and HIV infection and oral-genital transmission.”
Hepatitis C can be spread
through anal or even oral sex rarely, but it is much more common if the person is co-infected with HBV or HIV. (
www.medscape.com/viewarticle/580034 Sept. 4, 2008)
1.1.4b Occupational exposure
The general consensus is that HCV is a greater threat to healthcare workers than HIV. The risk that healthcare workers will become infected with hepatitis C virus (HCV) following an accidental needlestick injury is 20 to 40 times greater than their risk of HIV infection. (According to data presented at the International Conference on Emerging Infectious Disease, Sponsored by the US Centers for Disease Control and Prevention and the American Society for Microbiology in July 2000.
HCV exposure is possible in any occupation that could involve contact with infected blood, (i.e., nurses, phlebotomists, emergency medical technicians, firemen, and police to name a few). The risk of HCV infection following a needlestick injury with HCV-contaminated blood may be as high as 10%. Nonetheless, the risk of occupational transmission of HCV to Health Care Workers is far less than that of HBV.
Current recommendations are that "both private and public health providers be made aware of the risk, and above all that all source patient providers be tested for hepatitis C." (Dr. Robert T. Ball www.hepnet.com/hepc/news072000.html )
1.1.4c Toothbrushes/razors/nail clippers
It is possible for toothbrushes, razors, nail clippers, tweezers, and similar personal care items to come in contact with infected blood. It is safer not to share personal items, especially for people infected with hepatitis C. Recently concern was expressed over the sharing of electric razors in a VA hospital and in prisons. A study in Hepatology showed that 19% of veterans tested in a VA hospital in San Francisco were infected with HCV.
1.1.4d Hemodialysis
Patients on hemodialysis have higher rates of hepatitis C viral infection. It is vital that hospitals stick to strict infection control
practices and that hemodialysis patients be tested regularly for HBV and HCV. (Minerva Urol Nefrol. 2005 Sep;57(3):175-97.)
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