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

proven. It is assumed that introducing infested camelids could reintroduce the disease into
the sheep population. Therefore, the likelihood of exposure is assessed to be low but nonnegligible.
33.2.3. Consequence assessment
E. granulosus can infest cattle, sheep and goats, pigs, camelids, wild and feral ruminants,
and macropods such as wallabies that occur in New Zealand. Wild and feral animals could
be involved in maintaining and disseminating the parasite to dogs. The presence of the
parasite in animals other than sheep could result in transmission to sheep and the reestablishment
of a sheep/dog cycle and sporadic cases of human disease.
Re-establishment of the parasite in a dog/sheep cycle in New Zealand would have
consequences for human health. Neither dogs nor intermediate hosts develop clinical signs
of infestation, and control or re-eradication programmes would be implemented on human
health grounds (Pharo 2002). This could be a lengthy and expensive process dependent on
the extent to which the parasite has become dispersed.
In view of the above, the consequence assessment is assessed to be non-negligible.
33.2.4. Risk Estimation
Since entry, exposure, and consequence assessments are all non-negligible, the risk
estimate is non-negligible and E. granulosus is classified as a hazard in the commodity.
Therefore, risk management measures may be justified.
33.3. RISK MANAGEMENT
33.3.1. Options
The following points were considered when drafting options for the effective management
of Echinococcus granulosus in the commodity:
� New Zealand has eradicated E. granulosus.
� Hydatid-free flocks or herds are not defined in the Code and it is doubtful if the
disease is reportable in most countries.
� No reliable tests are available for the ante-mortem diagnosis of hydatid cysts in
intermediate hosts. Serological tests have low sensitivity and are not generally
available.
� Premise freedom is not a practical option because hydatids can be diagnosed in
intermediate hosts only by post-mortem inspection of offal. Therefore, the only
properties that could claim historical freedom would be those that regularly sent a
significant number of animals to slaughter at a plant where hydatids was recorded if
found. This is unlikely to be feasible, particularly for properties that have only
camelids and where the disease is not notifiable.
� Newly developed vaccines for ruminants show promise but are not yet available for
general use.
122 ● Import risk analysis: Llamas and alpacas from specified countries MAF Biosecurity New Zealand