Prevalence of rabies in various species in yemen and risk factors contributing to the spread of the disease.
OBJECTIVES
This study aimed to describe for the first time the prevalence of the passively-reported rabies virus among different domestic and wild animals submitted to the Central Veterinary Laboratory from various areas in Yemen, and to study prevalence proportion ratios (PPR) that contributed to the spread of rabies among animals, and its transmission to humans.


METHODS
A brain sample was obtained from each of the 180 animals and tested for rabies virus by a direct fluorescent antibody test.


RESULTS
Out of the total number of animals involved in attacks on humans, 63.3 % were positive for rabies. Of these, dogs were the main animal involved in attacks with a percentage of 92%, of which 62.7% were positive for rabies. Of animals involved in attacks, 70.6% were males of which 60.6% were positive, and 29.4% were females of which 69.8% were positive. Males comprised 68.9% of the total human individuals attacked, of whom 62.9% were attacked by rabies-positive animals. The significant risk factors that contributed to the spread of rabies in general included the presence of poultry carcasses and other waste in the vicinity of the attacks (PPR = 9.5) with a percentage of 84.8%, followed by the time of year, in particular school vacations (PPR = 3.8) with a percentage of 78%.


CONCLUSION
Rabies is endemic in Yemen with a very high rabies-positive rate for animals involved in attacks, particularly for stray male dogs. Male children were most often involved in attacks by rabies-positive animals. The presence of food waste (particularly poultry carcasses) and school vacation periods were found to correlate significantly with increased risk for human exposure to rabies.
Rabies in Yemen Arab Republic, 1982 to 1986
Between 1982 and 1986 a total of 1,101 spedmens were submitted to the laboratory for rabies examination. Slides prepared from brain samples (Stanley, 1987) were subjected to the Direct Fluorescent Antibody Test (DFAT) using anti-nucleocapsid conjugate (Institut Pasteur, Paris) where the presence of fluorescing bodies in conjunction with positive and negative control slides was reported as a positive diagnosis. The overall percentage of positive cases varied between 40% and 69%. In the last few years many of the minor roads to isolated villages and areas have been improved resulting in easier access to vertednary facilities. Not surprisingly, therefore, submissions to the laboratory have increased annually. Approximately 96% of the positive samples came from dogs (Table I). The majority of cases in domestic farm animals had been attacked by dogs some time previously. Dogs are the main source of infection in Yemen Arab Republic (YAR). Cats are known to be highly susceptible to rabies infection and yet very few cases in cats were reported. Most cats in YAR are semi-domesticated and are often too swift to be bitten by a disorientated rabid dog. Conversely if they are caught they are invariably killed. Thus the very young and old cats are the most likely to contract rabies. Foxes when they come into urban areas tend not to run away from the dogs thus making themselves another susceptible group. The ecology of the dog packs in YAR has not been studied. For example it is not known if they move through each others territory, how they maintain their seemingly stable numbers and how new packs are formed, all of which could have a bearing on how a future policy for rabies eradication could be formulated.
Comparative studies of α-Lactalbumin and lysozyme: Echidna lysozyme
Summaryα-Lactalbumin is a modifier protein for galactosyl transferase in the biosynthesis of lactose and lysozyme catalyses the cleavage of β(1–4) glycosidic linkages. It is now generally believed that α-lactalbumin and lysozyme have diverged from a common ancestor. Comparative studies of these proteins from several species are reported here.The presence of lactose and lactose synthetase activity is shown in mature milk samples from a variety of placental mammals (eutheria) and a pouch bearing mammal (marsupialia). The isolation of the α-lactalbumins involved and their properties are compared.The position is different in the milk samples of monotremes. The α-lactalbumin, lactose and lactose synthetase activity levels in the two platypus samples studied are very low. The levels of lactose and lactose synthetase activity in some echidna(Tachyglossus aculeatus) samples are low, but appreciable in others. No α-lactalbumin is present. The lysozyme activity is appreciable, some samples containing a different lysozyme from that present in others. One of these (designated echidna lysozyme I) is capable of lactose synthetase modifier activity in the presence of bovine “A protein”.The properties of this lysozyme are compared with those of lysozymes and α-lactalbumins from a variety of species and their significance is discussed.