The paradoxically low numbers of transmissible parasite forms in malaria infections (Taylor and Read, 1997) can also be explained by competition mediated by a shared immune response (McKenzie and Bossert, 1998).
Scrapie is a small ruminant, transmissible spongiform encephalopathy (TSE).
Because P. vivax is more frequently associated with gametocytemia [ 3, 9, 11] and is more transmissible at low parasite densities [ 18], the most commonly transmitted parasite after treatment for falciparum malaria, paradoxically, was not P. falciparum, but P. vivax.
Devil facial tumour disease (DFTD) infects Tasmanian devils, a critically endangered species with low genetic diversity, and transmissible hamster sarcoma spread via a vector through laboratory animals which shared sufficient genetic identity (Banfield et al. 1965).
We report here the complete nucleotide sequence of pEntH10407 (65 147 bp), an enterotoxigenic Escherichia coli enterotoxin plasmid (Ent plasmid), which is self-transmissible at low frequency.
AS/Nor98 agent has been shown to be experimentally transmissible, though at low efficiency, to sheep [ 23] and to transgenic mice expressing ovine [ 24] and porcine PrP [ 25].
If animals with asymptomatic infections are chosen, the resulting virus will be a highly transmissible virus with low pathogenic potential (Wain-Hobson, 2013).
In experimentally-induced transmissible mink encephalopathy, low concentrations of agent occurred in liver, kidney, intestine, and salivary gland only after replication in the CNS and in some lymphoreticular tissues (33 ).
However, it is difficult to exclude the possibility that AS is naturally transmissible at a low level and precautionary measures including the continued monitoring of animals leaving the flock are sound.
In fact, our quantitative analyses show that Newcastle disease virus is highly transmissible in poultry with low antibody titres.
