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Page 26 Jaswant et al. One Health Implement Res 2024;4:15-37 https://dx.doi.org/10.20517/ohir.2023.61

lower rate, 9.5 km/year, in crab-eating foxes, which was attributed to human activities driving dispersal of
[147]
dog-associated lineages . A high velocity of dog-meditated rabies (18.1 km/year), was estimated in Iran,
using a novel analytical framework, revealing spread linked to accessible areas associated with high human
[18]
density . This estimate is similar to the average dispersal rate in Northern Africa (19.5 km/year) where,
again, landscape accessibility was an important driving factor [18,32] .

The time of introduction and history of rabies spread in various areas was investigated. A publication used
historical records and phylogenetic analysis to show that rabies was only present in bats and skunks in the
Western Hemisphere, with canine rabies rare or absent among dogs of Native Americans, before the arrival
of new dog breeds imported during European colonisation . A more comprehensive recent study
[56]
combined partial and whole genome sequences to reconstruct movement more precisely, revealing how
colonial empires influenced the global spread of RABVs .
[148]
Human-mediated long-distance movement was identified through phylogeographic analysis as the source
of incursions into previously rabies-free areas, posing a challenge to maintaining rabies freedom. Examples
identified introductions to historically rabies-free areas such as island provinces in Indonesia and the
[138]
[78]
Philippines , and to areas where rabies had been eliminated such as Pemba, (an island off mainland
Tanzania ), Gauteng Province in South Africa, and N’Djamena, Chad .
[13]
[149]
Geographical features were discussed in fifteen papers, with rivers, lakes and mountain ranges shown to be
natural barriers [32,150,151] . For example, sequences within AF1b subclades (AF1b-1 and AF1b-11) were
[150]
separated by the Zambezi river and Kariba lake in Zambia and Zimbabwe respectively . Transboundary
spread between Lesotho and KwaZulu-Natal in South Africa was limited by the Drakensberg and Maloti
mountain ranges, which constrain movement of people and animals . In Asia, three lineages from SEA5
[151]
found in ferret badgers were segregated by mountain ranges and rivers [111,119] . Transmission corridors that
facilitated dissemination included: (1) transportation networks; (2) the presence and size of dog populations
(tied to human populations); and (3) anthropogenic factors (trade, agriculture and urbanisation). For
example, in Southeast Brazil, urbanisation was reported to play a central role; dog population size was
correlated with human populations, meaning higher density regions had more dogs and therefore more
[152]
RABV diversity . Road networks were often shown to be associated with increased movement, consistent
with human-mediated transport of incubating animals. RABV detected from different cities in Mozambique
[100]
were closely related, despite long distances between them . Sequences from the AF2 clade were proposed
to result from an introduction to Bangui, the capital of the Central African Republic, as the closest related
[14]
sequences were from neighbouring Chad . In Asia, transport routes were correlated with the RABV
distribution in Thailand , and China . At more local scales in Tanzania phylogeographic analysis
[153]
[154]
revealed that presence of dogs, rather than density, predicted spread .
[155]
Rabies control
All studies provided recommendations for rabies control and prevention, but most were generic and not
specifically inferred from sequences. These studies recommended mass vaccination of dogs, as well as oral
vaccination in specific wildlife populations where variants had emerged [156,157] . Other recommendations
included dog population management [76,113,158,159] , monitoring the health of animals for trade and
consumption [75,80,97,129] , and raising awareness, particularly in communities identified as “high-risk” [155,158,160,161] .
Only 33 publications provided targeted recommendations grounded in genetic evidence. Some reported
spillover events, emphasising the necessity for enhanced surveillance (n = 12) for specific wildlife
populations [59,72,93,95] . Outbreak investigations pinpointed sources of incursions, and recommended
monitoring for animal transport and at borders [78,82,138,162] plus surveillance and control measures in rabies-