Reader Comments

Post a new comment on this article

Response to the commentary

Posted by WenbaoZhang on 04 Nov 2009 at 11:34 GMT

The Expert Commentary made by Maria Vang Johansen and Mary-Lou Penrith was in response to the article entitled “A Pilot Study for Control of Hyperendemic Cystic Hydatid Disease in China” by Zhang et al. [1]. As co-authors of [1], we make the following points which we would like to elaborate on in our own response to the commentary.

Firstly, we declare that our data were all valid including ethical issues. We never used “enforcement” in any way to force villagers to cull any animals including stray and unwanted dogs. So, it is not clear what the authors want to imply as all the procedures were approved by the local committees and accepted by the local communities as we indicated in the article.

We agree that “Culling animals has been used in many parts of the world as a highly effective way to control and eliminate various infectious diseases of both veterinary and human health importance” as the authors indicate. In fact, culling animals is a very natural procedure of any biological species and culling animals has been approved to be a crucial measure for controlling hydatid disease in hyper endemic areas [2]. We believe it should be a measure considered for use in western China and elsewhere in areas with hyper endemic hydatid disease although the procedure must be carried out humanely.

In addition, we believe that ethical standards should not be the same in different communities with different ethnic backgrounds, especially when a particular host animal plays a key role in transmission of a disease that causes a significant problem in public health, such as dogs playing a key role in transmission of hydatid disease in western China where up to 12% of the population are infected. In these circumstances, culling stray and unwanted dogs is necessary as these animals play a significant role in transmission of hydatid disease. Culling procedures must be approved by local ethics committees and local communities. However, “market-level compensation” for dog owners did not arise in this study as the stray or unwanted dogs and had no owners

Taking stray and unwanted dogs into account for research design is scientifically correct, but ethically it should be avoided when it is clear that these dogs play a role in the transmission as they transfer the disease to communities. So, we cannot agree with the authors’ suggestions for controlling hydatid disease in hyper endemic areas as the statements they make are very contradictory and ill informed.
Wenbao Zhang
Zhuangzhi Zhang
Donald P. McManus

1. Zhang W, Zhang Z, Yimit T, Shi B, Aili H, Tulson G, You H, Li J, Gray DJ, McManus DP, Wang J (2009) A pilot study for control of hyperendemic cystic hydatid disease in China. PLoS Negl Trop Dis. 3:e534.

2. Craig PS, Larrieu E (2006) Control of cystic echinococcosis/hydatidosis: 1863-2002. Adv Parasitol 61: 443-508.

No competing interests declared.