It is quite possible that endemic centres [of skeletal fluorosis] exist but that the cause of the disabling spondylitis or other joint affections has not been determined, and a diagnosis of chronic arthritis has resulted. Few cases in Canada or the United States will be found to be as dramatic as that recorded here from Southwest China, but by calling attention to the advanced stage of this condition help may be afforded to the diagnosis of early cases.
… During our anthropological studies we were puzzled by the high incidence of a peculiar type of “arthritis” and joint ankylosis that seemed to afflict a majority of small Miao villages in the neighbourhood [in Southwest China]. In fact, in many of the older people the disease had advanced to such an extent that they appeared to be “set” in semi-sitting positions, with almost complete loss of movement in the limbs. The people there informed us that all children born and brought up in these villages became affected by the time they were 17 or 18 years of age. At the time we came to no conclusion in regard to the etiology of this condition, perhaps because although all of those affected had mottled enamel large numbers of the non-affected persons also showed mottling, many of them to a marked degree.
… there seemed to be a definite connection between the development of joint symptoms and poverty or intercurrent infections, since the disease appeared to be much more severe in thos who had the least opportunity for healthy living. A similar opinion has been expressed by Pundit at al.(4) in regard to endemic fluorosis in India.
The villagers asserted that the usual onset of the disease occurred at about the age of 10 years or in the early ‘teens, and started with a fever during which the patient complained of coldness and numbness. Then more or less gradually stiffness developed in various joints and the patient became a hunchback and a cripple. In the most acute cases death occurred at about 18 but if the disease became chronic the patient often lived to be 50. Another point noted was that pigs were the only domestic animals which developed any disease which the villagers connected with the human condition. They were the only animals which shared a common water supply with their human masters… No affected pigs were seen by us, but according to statements made by the local people only pregnant sows were affected, and they usually died soon after the birth of their young, unless these were removed at once.