Читать книгу Assisted Reproduction Techniques - Группа авторов - Страница 43

Hepatitis C virus (HCV) is an RNA virus thought to affect approximately 143 million people worldwide. Although the incidence is not well understood, as most infected people are asymptomatic, it is estimated that 1.75 million people are infected each year. Prevalence is highest in Central and East Asia, North Africa and the Middle East. Of those infected, 70–85% develop chronic liver disease, of which 20% develop cirrhosis and 5–7% die of HCV sequelae [5].

HCV is transmitted primarily by blood to blood contact, from blood transfusions and unsafe drug injections. Less frequently, HCV can be transmitted perinatally or through sexual transmission. Acute HCV symptoms develop in 20–30% of those infected, 4–12 weeks after transmission. Symptoms include flu like illness, nausea, vomiting and jaundice. Diagnosis of HCV infection is made by serological testing for anti‐HCV antibody, which becomes positive 6–8 weeks after transmission or by HCV RNA PCR testing [6].

Table 5.1 Clinical interpretation of serological markers of hepatitis B virus infection [1].

HBV serological test	Results	Clinical interpretation
HBsAgAnti‐HBcAnti‐HBs	NegativeNegativeNegative	Susceptible
HBsAgAnti‐HBcAnti‐HBs	NegativePositivePositive	Immune due to previous HBV infection
HBsAgAnti‐HBcAnti‐HBs	NegativeNegativePositive	Immune due to HBV vaccination
HBsAgAnti‐HBcAnti‐HBsIgM anti‐HBc	PositivePositiveNegativePositive	Acutely infected
HBsAgAnti‐HBcAnti‐HBsIgM anti‐HBc	PositivePositiveNegativeNegative	Chronically infected/ carrier
HBsAgAnti‐HBcAnti‐HBs	NegativePositiveNegative	Unclear interpretation. Possibly:Resolved HBV infection (most common)Low‐level chronic infectionResolving acute infection

There is no vaccine against HCV; prevention is focused around harm reduction by encouraging safe needle use and screening blood products. Antiviral medications have been developed to cure chronic liver disease resulting from HCV. However, left untreated, chronic HCV infection can also lead to cirrhosis and liver cancer [5].

The European Society of Human Reproduction and Embryology (ESHRE) recommends that HBV and HCV screening should be undertaken in both partners before performing assisted reproductive techniques (ART). This is to reduce the risk of transmission to the partner and neonate whilst also ensuring that the gametes and embryos can be handled with precaution.