Accurate and early diagnosis of animal rabies is critical for undertaking public health measures. Whereas the direct fluorescent antibody (DFA) technique is the recommended test, the more convenient, direct rapid immunochemistry test (dRIT), as well as the more sensitive, reverse transcription polymerase chain reaction (RT-PCR), have recently been employed for the laboratory diagnosis of rabies. We compared the three methods on brain samples from domestic (dog, cat, cattle, buffalo, horse, pig and goat) and wild (leopard, wolf and jackal) animals from various parts of India. Of the 257 samples tested, 167 were positive by all the three tests; in addition, 35 of the 36 decomposed samples were positive by RT-PCR. This is the first study in which such large number of animal samples have been subjected to the three tests simultaneously. The results confirm 100% corroboration between DFA and dRIT, buttress the applicability of dRIT in the simple and rapid diagnosis of rabies in animals, and reaffirm the suitability of RT-PCR for samples unfit for testing either by DFA or dRIT.

Detection of mastitis-associated bacteria can be accomplished by culturing or by molecular techniques. On the other hand, rapid and inexpensive methods to enumerate bacterial load without culturing can be better achieved by molecular methods. Staphylococcus aureus and Escherichia coli are the predominant bacterial pathogens associated with bovine mastitis. Here, we describe the application of conventional PCR for the limit of detection (LOD) of genomic DNA of S. aureus and E. coli based on single-copy genes. The selected genes were thermonuclease (nuc), aureolysin (aur), and staphopain A (scpA) for S. aureus and β-D-glucuronidase A (uidA), cytochrome d oxidase (cyd), and rodA (a gene affecting cell shape and methicillin sensitivity) for E. coli. The LOD was 5.3, 15.9, and 143 pg for aur, nuc, and scpA genes, corresponding to S. aureus genomic copies of 1.75 × 10(3), 5.16 × 10(3), and 4.71 × 10(4), respectively. The LOD was 0.45, 12.3 and 109 pg for uidA, rodA and cyd genes, corresponding to E. coli genome copies of 8.91 × 10(1), 2.43 × 10(3), and 2.16 × 10(4), respectively. Application of uidA and aur PCRs to field strains revealed that as low as approximately 100 genome copies of E. coli and 1000-10,000 copies of S. aureus could be detected. This study is the first to report LOD of genomic DNA using conventional PCR for aur and scpA genes of S. aureus, and rodA and cyd genes of E. coli. The results should be useful for developing assays to assess bacterial load in milk and to determine the load that contributes to subclinical or clinical mastitis.

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Rickettsia felis bacterium has been observed since the early twentieth century in the cat flea. It was grown for the first time in my laboratory on cell Xenopus then insect cells particularly Aedes albopictus cells. It grows only at temperature under 30 • C. First described in California, the bacterium is present in the whole world. For a long time it was considered a rare disease associated with fleas. In fact, in recent years, Rickettsia felis was found as the most frequently identified bacteria in patients with fever in tropical countries after malaria. These data were confirmed in West Africa and East Africa by different teams. Rickettsia felis has also been detected in tropical and tropical areas of South America, Asia and Oceania. Rickettsia felis and is the most common rickettsial currently in the world and very frequently associated with fever in the tropics and cough but no rash. In contrast controls without fever, can cause at a lower but significant level, the presence of Rickettsia felis DNA. So these circulations of Rickettsia felis in the blood that are not always associated with fever. Possible vectors in tropical areas may be mosquitoes in Africa. Rickettsia felis has the same epidemiological distribution as malaria. Rickettsia felis was found in Anopheles species and Aedes albopictus. A mouse experimental model was established showing that Rickettsia felis could be vectorized by Anopheles gambiae. Rickettsia felis, finally, recently, was found in book lice in the dust, which further complicates the epidemiological cycle of this bacterium. R. felis may be the most common bacteria emerging