With Wikipedia there is a similar situation. The Wikipedias that provide the best medical information are in languages where information is elsewhere also readily available.
Translating Wikipedia articles of high quality is definitely a great way of kick-starting the provision of health information in languages like Arabic, Hindi and Swahili. This does not mean that such articles will be perfect. The prevalence of many health issues is not evenly spread around the world, malaria and leprosy to name just two. The practices in the health sector are also very different. It is for this reason that it is so welcome that translators are urged not only to translate but also to localise the content.
It is icing on the cake that Healthspeaks offers a reward for every word translated to a local charity involved in health care. All in all, this looks like a well conceived project and I hope many people will register and make it a success.