Andean Latin America
2.0 1.0 million
Central Latin America
1.6 3.4 million
Southern Latin America
1.6 0.9 million
Tropical Latin America
1.2 2.3 million
North AfricaMiddle East
3.6 15 million
North America
1.3 4.4 million
Oceania
2.6 0.2 million
Central sub-Saharan Africa
2.3 1.9 million
East sub-Saharan Africa
2.0 6.1 million
South sub-Saharan Africa
2.1 1.4 million
West sub-Saharan Africa
2.8 8.4 million
Source: Adapted from Mohd Hanaiah et al., 2013
1
Certain groups are at higher risk of HCV infection, and estimates of the prevalence of HCV in these groups are shown in Table 2.2. The relative importance of risk
factors for HCV infection varies substantially, depending on the geographical region and population studied. Greater access to HCV testing and better
surveillance are important steps to both increase the number of persons diagnosed with HCV and to improve understanding of the distribution of HCV
infection in the general population and groups at increased risk.
2.1.1 Routes of transmission
Population Comment
Persons who inject drugs
6
PWID have the highest risk of infection: Globally, the prevalence of HCV is 67 among PWID.
Recipients of infected blood products or invasive
procedures in health-care facilities with inadequate
infection control practices
7-16
Risk of HCV infection varies depending upon the frequency of medical procedures i.e. number of injectionspersonyear and
level of infection-control practices. High frequency of injections and low level of infection control can result in high prevalence of
HCV in the general population e.g. prevalence of chronic HCV infection conirmed by nucleic acid testing was 9.8 in Egypt in
2008
Children born to mothers infected with HCV
17, 18
HCV transmission risk is estimated as 4–8 among mothers without HIV infection
Transmission risk is estimated as 17-25 among mothers with HIV infection
TABLE 2.2 Populations at increased risk of HCV infection
People with sexual partners who are HCV-infected
19,20-23
There is low or no risk of sexual transmission of HCV among HIV-uninfected heterosexual couples and HIV-uninfected men
who have sex with men MSM. The risk of sexual transmission is strongly linked to pre-existing HIV infection.
People with HIV infection
23-31
Persons with HIV infection, in particular MSM, are at increased risk of HCV infection through unprotected sex.
People who have used intranasal drugs
32
Non-injecting drug use e.g. through sharing of inhalation equipment for cocaine is associated with a higher risk of HCV
infection. People who have had tattoos
or piercings
33
Tattoo recipients have higher prevalence of HCV compared with persons without tattoos odds ratio = 2.24, 95CI 2.01,2.50
Health-care associated transmission Hepatitis C virus infection is strongly associated with health inequity; in low- and
middle-income countries, infection with HCV is most commonly associated with unsafe injection practices and procedures such as renal dialysis and unscreened
blood transfusions.
15,34
Between 8 and 12 billion injections are administered yearly around the world and 50 of these are considered to be unsafe mainly in sub-
Saharan Africa and Asia.
35
In low- and middle-income countries, infection with HCV is frequently associated with unsafe injection practices and unscreened or
inadequately screened blood transfusions. According to the latest WHO report on blood safety 2011, 39 countries do not routinely screen blood transfusions
for bloodborne viruses.
36
The most well documented example of health-care associated transmission is the generalized epidemic of HCV infection resulting
from unsafe injection practices in Egypt, where HCV prevalence is 25 in some regions.
8
Persons who received untested blood products prior to the introduction of screening of blood for HCV in high-income countries are also at risk. Universal
access to safe blood transfusion requires the implementation of key strategies to ensure access to a safe and suficient blood supply, including the implementation
of 100 voluntary blood donation and 100 quality-assured testing of donated blood. WHO has developed guidelines on best practices in phlebotomy and best
practices for injections and related procedures.
37
People who inject drugs In middle- and high-income countries, most HCV infections occur among people
who use unsterile equipment to inject drugs and contaminated drug solutions. Of the estimated 16 million people in 148 countries who actively inject drugs, 10
million are infected with HCV.
6
PWID infected with HCV are at increased risk of all-cause mortality, relecting the role of injecting drug use, low socioeconomic
status, poor access to health care and environmental factors.
38
Mother-to-child transmission The risk of transmission of HCV from a mother to her child occurs in 4–8 of
births to women with HCV infection and in 17–25 of births to women with HIV and HCV coinfection Table 2.2.
17,18
Sexual transmission Sexual transmission of HCV occurs infrequently in heterosexual couples.
39
It is more common in HIV-positive persons, particularly in men who have sex with men MSM.
40
In several recent outbreaks of HCV infection among MSM in Europe, Australia and the US, transmission has been linked to sexual exposure as well as potentially to
underreported use of non-injecting recreational drugs.
41,42
HIV-infected heterosexual partners of HCV-infected people are also more likely to acquire HCV; this may be
due to sexual transmission or other exposure to blood or due to unreported injection or non-injection drug use, such as sharing of straws for inhaling cocaine.
41
Other Other routes of transmission of HCV include intranasal drug use and other
modes of bloodborne transmission, such as acquisition by health-care workers, cosmetic procedures such as tattooing and body piercing, scariication and
circumcision procedures.
33,43
2.1.2 Coinfections
