Import risk analysis: Llamas (Lama glama) and alpacas (Vicugna ...

36. Ticks
36.1. HAZARD IDENTIFICATION
36.1.1. Aetiological agent
World-wide there are around 170 species of Argasidae or soft ticks and 650 species of
Ixodidae or hard ticks (Allan 2001). Species known to infest camelids are discussed in
Section 36.1.4.
36.1.2. OIE list
Ticks are not listed in the Code. However, several tick species are vectors of diseases
included in the OIE list.
36.1.3. New Zealand status
There are nine species of tick in New Zealand, most of which are found on wild birds.
Only one species of cattle tick, Haemaphysalis longicornis, is of economic importance to
livestock. Five genera of ticks are listed as unwanted notifiable organisms on the
Unwanted Organisms Register:
Amblyomma spp.
Boophilus spp.
Dermacentor spp.
Ixodes spp.
Rhipicephalus spp.
36.1.4. Epidemiology
Ticks cause serious economic losses. Losses are worse in hot tropical climates but also
occur in countries with temperate climates. Ticks are vectors for a large number of diseases
and tick toxicoses. Norval and Horak list 33 diseases and toxicoses of livestock that occur
in Southern Africa (Norval & Horak 2004). The list is not complete even for Africa and
does not include diseases of cats, dogs, wildlife species, and humans. Allan lists nine
diseases that occur in North America (Allan 2001). Many other diseases occur in other
countries. The livestock diseases carried by ticks include economically important diseases
such as heartwater, babesiosis, anaplasmosis, theileriosis, and African swine fever.
World-wide losses due to tick-borne diseases and tick control have been estimated to cost
several billion dollars annually (Jongejan & Uilenberg 1994). Apart from losses due to
diseases carried by ticks, infestations with ticks also cause significant production losses
and losses for tick control (Jonsson et al 2000; Jonsson et al 2001).
New Zealand has only one livestock tick, Haemaphysalis longicornis, and no significant
tick-borne diseases. Many important ticks such as Amblyomma spp. might not be able to
establish themselves in the New Zealand environment, but it is considered that New
Zealand’s mainly moist-temperate climate provides an ideal environment for all but the
most strictly tropical or arid region tick species (Heath 2001).
Consideration of the lifecycles of ticks is important when designing programmes to prevent
the entry of ticks into New Zealand.
136 ● Import risk analysis: Llamas and alpacas from specified countries MAF Biosecurity New Zealand