Routes of nosocomial transmission of HCV

1
Routes of nosocomial transmission of HCV

• Valentina Liakina
• Centre of Hepatology, Gastroenterology and
  Dietetics
• Faculty of Medicine
• Vilnius University
• St. Petersburg, 2012-04-03

2
Topicality
Nosocomial transmissions of HCV account for a
large proportion of new HCV infections in the
Western world.
For instance hospital admission was the only
risk factor in about two-thirds of acute
hepatitis C cases in Spain Santantonio T, 2006
and Italy Martinez-Bauer E, 2008 and in 15 of
patients registered in Hep-Net acute HCV database
of Germany Deterding K, 2008
3
Data from the study of risk factors for HCV
acquisition in chronic hepatitis C patients
Chronic hepatitis C cohort, n1158 Multivariate
logistic regression analysis of HCV risk factors
depending on the age Surgery OR1.571,
p.0236 Long-lasting and multiple
hospitalizations OR2.330, p.0045 are
independent risks for HCV acquisition
Multivariate logistic regression analysis of
HCV risk factors depending on the
gender Donations OR0.285, plt.001 Long-lasting
and multiple hospitalizations OR0.383, p.0144
Surgery OR2.314, p.0013 Occupational
exposure OR4.329, p.0059 Liakina V, 2009
4
Data from the study of anti-HCV prevalence in
general population of Lithuania
General population, n1514 No one of risk factor
studied was confirmed as independent by
multivariate logistic regression
analysis. Univariate logistic regression
analysis of risk factors for anti-HCV
positivity Intravenous drug use OR42.5,
plt.0001 Long-lasting and multiple
hospitalizations OR3.056, p.0064 Tooth
removal OR 4.141, p.0048 Childbirth OR5.056,
p.0224 Surgery, abortions, dentistry,
hemodialysis, blood donations and transfusions
were not confirmed as risks for anti-HCV
positivity. Liakina V, 2012
5
How HCV can be transmitted in the health care
unites
Breaches in aseptic techniques Blood and blood
products transfusions (paid donations) Asymptomat
ic HCV carriers (patients and health care staff)
6
Why aseptic techniques are not save concerning
HCV transmission?

• HCV contaminated materials and infusions
  represent a substantial risk for transmission,
  because HCV is surprisingly stable at room
  temperature (up to 2 weeks), even dried and
  stored HCV plasma is infectable up to 16 hours
  Kamili S, 2007
• HCV infectivity in a liquid environment was
  detectable for up to 5 month at lower
  temperatures. Ciesek S, 2010
• Different alcohols and commercially available
  antiseptics reduced the infectivity of HCV to
  undetectable levels. However, diluting the hand
  disinfectants abrogated the virucidal activity.
  Ciesek S, 2010
• Until now there are lack of data available
  regarding HCV stability and sensitivity toward
  chemical disinfectants

7
Why blood donation still are not save concerning
HCV transmission?

• Sufficient HCV RNA quantity for detection appears
  only after 4-5 days of HCV infection. Even when
  HCV RNA is tested separately in every donation,
  not in pools, and NAT sensitivity is 3.01 IU/ml
  only 8 copies per 1 ml can be detected.
• Still up to 8 copies of viral RNA per 1 ml blood
  can be transfused to the recipient.
• 400 ml blood3200 HCV

Insufficient sensitivity of HCV RNA detection
methods

1. HCV carriers are asymptomatic and feel themselves
   healthy
2. The risk to get HCV-infected blood increases when
   paid donations are practiced
3. The risk of HCV infection may not accurately be
   reflected by determination of HCV RNA levels,
   because viral infectivity and HCV RNA copy
   numbers did not directly correlate.

8
Asymptomatic HCV carriers (patients and health
care staff)

• Patient-to-patient HCV transmission
• Provider-to-patient HCV transmission
• Patient-to-provider HCV transmission

9
Patient-to-patient HCV transmission

• In hemodialysis settings because of
• contaminated dialysis machines Delarocque-Astagne
  au E, 2002,
• inadequate infection control of procedures
  Abacioglu J, 2000,
• dialyzing infected and noninfected patients in
  the same area Petrosillo N, 2001
• HCV-infected hemodialized patients worldwide 4
  70 Wreghitt T,
• 1999, in USA 1.7 in staff, 8.4 in patients
  Tokars J, 2002
• Gynecological and endocrinological procedures
  Massari M, 2001
• Contamination of multidose vials and intravenous
  administration devices (shared saline bags,
  contaminated when reused syringes were used to
  draw blood from venous catheters Macedo de
  Oliveira A, 2005)
• Contaminated equipment spring-loaded
  finger-stick devices Desenclos JC, 2001,
  anesthesia assistant's interventions Ross R,
  2002, endoscopy Muscarella L, 2001,
  colonoscopy Bronowicki J, 1997,
  Gonzalez-Candelas F, 2010
• Organ transplantation Wreghitt T, 1994
• Dentistry
• Assisted reproduction procedures Abou-Setta A,
  2004
• In oncology wards Dencs A, 2011

Some, if not most, of these instances of HCV
transmission most likely represent
cross-contamination, due, at least in part, to
inadequate infection control procedures or
inadequate disinfection of devices or objects
10
Provider-to-patient HCV transmission
Iatrogenic transmission of HCV from HCV-infected
providers to their patients has been uncommon.
The first suggestion of iatrogenic infection was
reported from England in 1995 ( from HCV-infected
surgeon during cardiovascular surgery Public
Health Laboratory Service, 1995), than in Spain
(6 from 222 patients been operated for valve
replacement by infected surgeon Esteban J,
1996, coronary artery bipass surgery PHLS,
1999. Till 2000 4,500 individuals get the same
HCV stains as surgeons had Pugliese G, 2000
PHLS, 2000 Overall in UK 0.12 of patients get
virus from the provider Cardiothoracic surgeon
Brouwn P, 1999 HCV-infected gynecologists
(caesarian section and other procedures) PHLS,
1999 7-years retrospective investigation Ross
R, 2002 Orthopedic surgeon (3 out of 207) Ross
R, 2002 Anesthesiologists and anesthesia
assistant's interventions Cody S, 2002,
Shemer-Avni Y, 2007 Eye surgery Jatoi Shm,
1999 Lot F, 2007,
11
A review carried out in 2005 documented that
worldwide five healthcare workers had transmitted
hepatitis C to a total of 232 patients. Reitsma
A, 2005
HCV-infected mother transmit virus to her
hemophilic child after she stuck her own finger
with the needle for the infusion Morb.
Mortal.Wkly., 1997
12
SHEA Guideline for Management of Healthcare
Workers Who Are Infected with Hepatitis B Virus,
Hepatitis C Virus, and/or Human Immunodeficiency
Virus 2010 USA Henderson DK, 2010 This
guideline provides the updated recommendations of
the Society for Healthcare Epidemiology of
America (SHEA) regarding the management of
healthcare providers who are infected with
hepatitis B virus (HBV), hepatitis C virus (HCV),
and/or the human immunodeficiency virus
(HIV). HCV-infected provider is allowed to
perform I and II categories of procedures using
double-gloving for all invasive procedures, but
not allowed to perform III category procedures
13
This guidance is intended to assist in
implementation of the joint chief professionals
letter HSS(MD)9/2011 Hepatitis C Infected
Healthcare Workers Guidance on the prevention of
healthcare-related hepatitis C and workplace
management of hepatitis C infected clinical
healthcare workers. It is also available on the
DHSSPS web site at www.dhsspsni.gov.uk/hss-md-9-20
11-guidance.pdf, 2011 For all surgeons, dentists,
other practitioners performing EPPs.
Existing healthcare workers who know that they
have been infected with hepatitis C (i.e. who
have antibodies to hepatitis C virus) and who
carry out EPPs should be tested for hepatitis C
virus RNA. Those found to be carrying the virus
(i.e. who are hepatitis C virus RNA positive)
should be restricted from performing EPPs in
future, unless they have responded successfully
to treatment. Healthcare workers, who perform
EPPs should promptly seek and follow confidential
professional advice on whether they should be
tested for hepatitis C. Testing should be for
antibodies to hepatitis C virus, and if positive,
for hepatitis C virus RNA.
EPPs are those invasive procedures where there
is a risk that injury to the worker may result in
exposure of the patient's open tissues to the
blood of the worker.
14
Patient-to-provider HCV transmission
1997 and 2007 there were 14 patient-to-healthcare-
worker transmissions in England Health
Protection Agency, 2008
15
What would be good to do

• Check every patient for anti-HCV before invasive
  procedure
• Control of health care providers HCV status
• Use only voluntary blood donations
• In medical apparatus avoid multiple used tips and
  other details been in contact with pacients
  liquids
• Use as reliable as possible aseptic techniques.
  To define rigorous disinfection protocols.

16
Environmental HCV stability
17
Stability of blood samples infected with HCV

• Samples stored at 25 C maintain their HCV RNA
  titre during 14 days
• samples at 5 C were stable for at least 3 months
• Independently of the HCV RNA concentration, the
  results show absence of decay in HCV RNA
  detectability at -20 C, -70 C during 7 years of
  follow-up. Jose M, 2003
• Dried and stored HCV plasma is infectable up to
  16 hours at room temperature Kamili S, 2007

18
Heating kill HCV

• 65C 4 min
• 60C 8 min
• 56C 40 min Song H, 2010
• 37C for 2 days,
• room temperature 16 days Sattar SA, 2004
• 4C - the virus was relatively stable without
  drastic loss of infectivity for at least 6 weeks.
  Song H, 2010
• At lower temperatures - HCV infectivity in a
  liquid environment was detectable for up to 5
  month. Ciesek S, 2010

19
UVC light irradiation

• wavelength 253.7 nm with an intensity of 450
  µW/cm2 2 min. Song H, 2010
• (this could be a good flat surfaces sterilization
• method, but not suitable for rough and hollow
• parts of the medicine equipment)

20
Organic solvents and detergents

• Formaldehyde
• glutaraldehyde,
• ionic or nonionic detergents
• inactivate HCV effectively (depending on
  concentration) Song H, 2010