Donor to host transmission of disease via corneal transplantation.

A literature search was conducted to report all cases of documented transmission of infectious diseases from donors to recipients of corneal transplants. Fourteen such cases have been reported. There is no experimental or clinical evidence to suggest the transmissions of either hepatitis or syphilis via corneal grafting. Available evidence regarding a number of neurologic and other disorders in which a slow virus etiology has been implicated were reviewed. On the basis of this review, we are able to draw certain conclusions and guidelines for selection or rejection of donor material for transplant surgery.

Social and public health implication of water supply in arid zones in the Sudan.

The quantity and physical, chemical and bacteriological quality of water from wells, tap and zeers in Port Sudan and from wells, rectified and unrectified hafirs in South Kordofan Province were investigated. The relationship between water quantity and quality and prevalence of water-related diseases was also assessed. Both areas are semi-arid and tragically suffer from shortage of water. The average per capita consumption in Port Sudan was about 1001, and about 301, in South Kordofan. All water sources in both areas were invariably contaminated with coliforms. In South Kordofan the provision of water was primarily the responsibility of women and children. Depending on the crowds and the distance of the water source people spend between 3-5 hours per day carrying water. 50% of the families have to cover more than 2 km to reach the water source. It was evident that hafirs rectification increased the amount of water stored. Tap and zeer (home pots) water in Port Sudan was also contaminated with coliforms. The content of suspended and dissolved solids and turbidity of hafirs water was exceptionally high, which warrants proper protection and water treatment before distribution to the public. Scarcity of water rather than bacterial contamination was the cause of alarmingly high prevalence of diarrhoeal, skin and eye communicable diseases (water-washed diseases) among children and adults of Port Sudan and South Kordofan Province. However, it is plausible to suggest that even minor improvements on the provided quantity of water will reduce the prevalence of water-washed diseases.

A comparison of Texan and Hawaiian strains of the avian eyefluke, philophthalmus gralli, with a cautionary note on the importation of exotic animals.

Philophthalmus gralli (Mathis and Leger, 1910) was introduced into the San Antonio, Texas area within the last 25-30 years from an unknown foreign source. Strains of P. gralli originally from Texas and Hawaii were compared for differences in morphology, growth patterns, mating compatibility, and isozyme mobilities. Metacercarial cysts of the 2 strains were compared for viability after storage at room temperature. Adult stages of the 2 strains were indistinguishable based on sucker ratios, vitellaria, and egg sizes. In single- and multiple-worm infections, both strains exhibited similar growth patterns when reared in chickens. Adults of the 2 strains, when transplanted in concurrent infections, readily cross-inseminated. Isozyme mobilities of 5 enzymes were identical in all adult worms examined from both strains. After 3 days, metacercarial cysts from both strains rapidly lost their ability to excyst. The cysts of the Texan strain remained viable for 4 days longer than the Hawaiian strain, although excystment rates were low during that period. The evolutionary implications of this imported species are discussed.

Zoonotic visceral and ocular larva migrans.

Infection of children with the larval stage of the dog roundworm Toxocara canis usually produces few, if any, clinical signs. In some children, however, the disease may be severe, with permanent ocular or neurologic sequelae. Because the prevalence of infection may exceed 10 per cent in some population subgroups, it is important to understand the modes of transmission and risk factors for infection. The clinical presentations of toxocariasis as well as recommendations for their prevention are described.

Transmission of chronic idiopathic vitritis in mice by inoculation of human vitreous containing leucocyte phagolysosomal bacteria-like bodies.

Vitreous humour from chronic idiopathic vitritis (CIV) patients containing 0.5-0.7 micron diameter bacteria-like bodies (BLB) in polymorphonuclear leucocytes was inoculated into the eyelids of 100 mice. 200 control mice received either eye-bank vitreous or saline. After 12 months, 53 mice that received CIV vitreous, but none of the controls, had clinical signs of ocular inflammation (p less than 0.05); 15 of the mice that received CIV vitreous and none of the controls had histological evidence of chronic deep ocular inflammation, including vitritis (p less than 0.05); 95 CIV-vitreous-inoculated and 38 control mice were dead (p less than 0.05); and 3/3 of the CIV-vitreous group, compared with 0/3 controls, that were killed for histological assessment had phagolysosomal BLB identical to those in the CIV-vitreous inocula. The findings indicate that the BLB are pathogenic for mice.

Risk factors for toxocaral ocular larva migrans: a case-control study.

Twenty-four patients with serologically confirmed toxocaral ocular larva migrans (OLM) and 24 age- and sex-matched controls were the subjects of an epidemiologic study. Information on the exposure to dogs and other factors possibly associated with transmission of toxocariasis was obtained by contacting the parents of the subjects. The odds of having had a dog present in the household within the year previous to onset of illness were 3 to 1 for cases vs controls. An association of pups (< 3 months) in the households of OLM patients within one year of onset was statistically significant (P < .05). Twenty-three of 24 OLM patients had had dogs in their homes some time before their illness, and the twenty-fourth patient had a history of geophagia, a behavioral pattern previously identified as a risk factor for toxocariasis. Exposure to cats and other animals in or outside the home did not differ for patients and controls. Infected dogs, especially pups, in the patients' homes were the most probably sources of infection for this group of OLM patients.