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The impact of vaccination and antiviral therapy on hepatitis B and hepatitis D epidemiology.

Goyal A, Murray JM - PLoS ONE (2014)

Bottom Line: The major cause of liver cancer around the globe is hepatitis B virus (HBV), which also contributes to a large number of deaths due to liver failure alone.Hepatitis delta virus (HDV) is as potentially alarming as HBV since life threatening cases are 10 times more likely with HBV-HDV dual infection compared to HBV monoinfection.We further found that HDV presence results in lower HBV prevalence.

View Article: PubMed Central - PubMed

Affiliation: School of Mathematics and Statistics, University of New South Wales, Sydney, Australia.

ABSTRACT
The major cause of liver cancer around the globe is hepatitis B virus (HBV), which also contributes to a large number of deaths due to liver failure alone. Hepatitis delta virus (HDV) is as potentially alarming as HBV since life threatening cases are 10 times more likely with HBV-HDV dual infection compared to HBV monoinfection. So far, there is no established effective treatment against HDV and the only preventive action suggested by the World Health Organization is to introduce HBV vaccination for children immediately after birth (newborns) and thus reduce the available pool for HDV infection. Here the main objective is to understand the complex dynamics of HBV-HDV infection in a human population that can inform public health policy makers on the level of different preventive measures required to eliminate HBV and HDV infections. Model simulations suggest that HBV vertical transmission and HBV vaccination rates for newborns are instrumental in determining HBV and HDV prevalence. A decrease in HBV prevalence is observed as vaccination coverage increases and it is possible to eradicate both HBV and HDV using high vaccination coverage of ≥80% in the long term. We further found that HDV presence results in lower HBV prevalence. An application of our model to China revealed that vaccinating every newborn in China will further prevent 1.69 million new infections by 2028 as compared to the current 90% vaccination coverage. Although, higher vaccination coverage of newborns should eliminate both HBV and HDV over a long time period, any short term strategy to eradicate HDV must include additional preventive measures such as HBV adult vaccination. Implementation of HBV adult vaccination programs at a rate of 10% per year over 15 years will further prevent 39 thousand new HDV infections in China by 2028 as compared to HBV vaccination programs solely for newborns.

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Related in: MedlinePlus

How one virus infectivity impacts the other.(%) HBV and (%) HDV prevalence in the total population during HBV mono-infection (solid black line) and dual HBV-HDV epidemics (dotted red line and dashed dotted blue line) at  years relative to: (A) values of infectivity of acute HDV infection () on the x-axis with  also varying as ; (B) levels of suppression by HDV on the transmission of HBV in those dually infected individuals () on the x-axis with  also varying as .
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pone-0110143-g002: How one virus infectivity impacts the other.(%) HBV and (%) HDV prevalence in the total population during HBV mono-infection (solid black line) and dual HBV-HDV epidemics (dotted red line and dashed dotted blue line) at years relative to: (A) values of infectivity of acute HDV infection () on the x-axis with also varying as ; (B) levels of suppression by HDV on the transmission of HBV in those dually infected individuals () on the x-axis with also varying as .

Mentions: Since there is uncertainty around the individual transmission probabilities, we investigated the effect of different HDV transmission probabilities ( and the linked parameter ) on HBV and HDV prevalence in the total population after a time of 100 years (which is before the dynamics have reached equilibrium but which provided wider variation for prevalence across the parameter values investigated in these sections) assuming 90% HBV vaccination coverage at birth and other parameters as given in Table 1 (Figure 2(A)-(B)). As HDV infectivity increases HBV prevalence decreases to the point where it almost equals HDV prevalence. At this point HDV is sufficiently high to ensure virtually every individual who is HBV infected is also HDV infected. Lower HBV prevalence is then a consequence of the lower probability of HBV infection from a dually-infected individual than from a mono-infected individual, which results from suppression of HBV viremia with dual infection [35]. This impact of HDV on HBV prevalence is consistent with previous HDV modeling [16].


The impact of vaccination and antiviral therapy on hepatitis B and hepatitis D epidemiology.

Goyal A, Murray JM - PLoS ONE (2014)

How one virus infectivity impacts the other.(%) HBV and (%) HDV prevalence in the total population during HBV mono-infection (solid black line) and dual HBV-HDV epidemics (dotted red line and dashed dotted blue line) at  years relative to: (A) values of infectivity of acute HDV infection () on the x-axis with  also varying as ; (B) levels of suppression by HDV on the transmission of HBV in those dually infected individuals () on the x-axis with  also varying as .
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4196970&req=5

pone-0110143-g002: How one virus infectivity impacts the other.(%) HBV and (%) HDV prevalence in the total population during HBV mono-infection (solid black line) and dual HBV-HDV epidemics (dotted red line and dashed dotted blue line) at years relative to: (A) values of infectivity of acute HDV infection () on the x-axis with also varying as ; (B) levels of suppression by HDV on the transmission of HBV in those dually infected individuals () on the x-axis with also varying as .
Mentions: Since there is uncertainty around the individual transmission probabilities, we investigated the effect of different HDV transmission probabilities ( and the linked parameter ) on HBV and HDV prevalence in the total population after a time of 100 years (which is before the dynamics have reached equilibrium but which provided wider variation for prevalence across the parameter values investigated in these sections) assuming 90% HBV vaccination coverage at birth and other parameters as given in Table 1 (Figure 2(A)-(B)). As HDV infectivity increases HBV prevalence decreases to the point where it almost equals HDV prevalence. At this point HDV is sufficiently high to ensure virtually every individual who is HBV infected is also HDV infected. Lower HBV prevalence is then a consequence of the lower probability of HBV infection from a dually-infected individual than from a mono-infected individual, which results from suppression of HBV viremia with dual infection [35]. This impact of HDV on HBV prevalence is consistent with previous HDV modeling [16].

Bottom Line: The major cause of liver cancer around the globe is hepatitis B virus (HBV), which also contributes to a large number of deaths due to liver failure alone.Hepatitis delta virus (HDV) is as potentially alarming as HBV since life threatening cases are 10 times more likely with HBV-HDV dual infection compared to HBV monoinfection.We further found that HDV presence results in lower HBV prevalence.

View Article: PubMed Central - PubMed

Affiliation: School of Mathematics and Statistics, University of New South Wales, Sydney, Australia.

ABSTRACT
The major cause of liver cancer around the globe is hepatitis B virus (HBV), which also contributes to a large number of deaths due to liver failure alone. Hepatitis delta virus (HDV) is as potentially alarming as HBV since life threatening cases are 10 times more likely with HBV-HDV dual infection compared to HBV monoinfection. So far, there is no established effective treatment against HDV and the only preventive action suggested by the World Health Organization is to introduce HBV vaccination for children immediately after birth (newborns) and thus reduce the available pool for HDV infection. Here the main objective is to understand the complex dynamics of HBV-HDV infection in a human population that can inform public health policy makers on the level of different preventive measures required to eliminate HBV and HDV infections. Model simulations suggest that HBV vertical transmission and HBV vaccination rates for newborns are instrumental in determining HBV and HDV prevalence. A decrease in HBV prevalence is observed as vaccination coverage increases and it is possible to eradicate both HBV and HDV using high vaccination coverage of ≥80% in the long term. We further found that HDV presence results in lower HBV prevalence. An application of our model to China revealed that vaccinating every newborn in China will further prevent 1.69 million new infections by 2028 as compared to the current 90% vaccination coverage. Although, higher vaccination coverage of newborns should eliminate both HBV and HDV over a long time period, any short term strategy to eradicate HDV must include additional preventive measures such as HBV adult vaccination. Implementation of HBV adult vaccination programs at a rate of 10% per year over 15 years will further prevent 39 thousand new HDV infections in China by 2028 as compared to HBV vaccination programs solely for newborns.

Show MeSH
Related in: MedlinePlus