transmission is largely through national parks. To control the wildlife rabies, an AdV
serotype 5 vectored vaccine was developed. The vaccine that expresses the rabies
glycoprotein (AdRG1.3) is produced using HEK-293 cells. Then, AdRG1.3 AdV is
formulated and packaged into baits by Artemis Technologies Inc. using proprietary
technology [19]. To meet the requirement of field trails, AdRG1.3 AdV production
was successfully scaled up from 1 to 500 L. The results of field trials demonstrated
advantages of the vaccine in immunizing wild animals that were previously difficult
to vaccinate [19]. The vaccine is currently licensed for use in Canada.
11.2.3.1.2
AdV-Based Foot and Mouth Disease (FMD) Vaccine
Foot-and-mouth disease virus (FMDV) is a Picornaviridae RNA virus. FMD afflicts
cloven-hooved animals, including sheep, goats, cattle, pigs, and buffalo with pedal
and oronasal vesicular lesions. The virus can be transmitted through aerosol droplets,
direct contact, and ingestion with infected animals [57]. There are seven FMDV
serotypes, and numerous strains. In most countries throughout Africa and Asia, in-
activated vaccines are widely used to control outbreaks. Compared with inactivated
vaccines, the next-generation recombinant FMD vaccines that are produced without
virulent FMDV strains have more advantages, especially for a rapid response against
newly emerging FMDV. In 2012, Adt.A24 FMD vaccine was licensed by the U.S.
Department of Agriculture for conditional use to protect cattle [58]. The vaccine used
a replication-defective human AdV containing the capsid- and 3C protease-coding
regions of the A24 FMDV [59]. Previous studies demonstrated that this vaccine can
protect both swine and cattle with 64% efficacy [60].
11.2.3.2
AdV-Based Ebola Vaccine
First appearing in 1976 in Africa, Ebola is one of the most severe hemorrhagic fever
viruses. Causing a sudden high fever, followed by vomiting, diarrhea, and even
bleeding, Ebola has fatality rates of 20–90%. There are five known species of Ebola
including Zaire ebolavirus, Sudan ebolavirus, Taï Forest ebolavirus, Bundibugyo
ebolavirus, and Reston ebolavirus [61]. Since there have been no treatments so far,
it is vital to develop vaccines to control the disease. In 2017, China’s food and drug
authority approved a licence for the Ebola virus vaccine. An Ad5-EBOV vaccine
was developed by CanSino Biologics Inc., based on the same principle. The product
is stored as a stable lyophilized powder, which is convenient to transport and use in
remote areas. GlaxoSmithKline (GSK) developed a recombinant chimpanzee ade-
novirus type-3 vectored vaccine against Zaire Ebola (ChAd3-EBO-Z). It has been
registered with ClinicalTrials.gov (NCT02548078) for a phase two clinical trial.
ChAd3-EBO-Z was proved to elicit immunity and good tolerance in children aged
1–17 years [2]. Since about 20% of cases were reported in children during the large
Ebola virus outbreak in 2013–2016, the vaccine candidate developed by GSK
shows a great value.
11.2.3.3
AdV-Based COVID-19 Vaccine
Since the first report of a patient infected with acute respiratory syndrome cor-
onavirus 2 (SARS-CoV-2) in late 2019, over 240 million positive cases have been
reported worldwide so far, causing over 4.8 fatalities. Currently, four AdV-based
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Bioprocessing of Viral Vaccines