Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-9-13
pubmed:abstractText
The extrinsic development of Leishmania major was observed in 2 man-biting sand flies, Phlebotomus duboscqi, a known vector, and Sergentomyia schwetzi, an assumed non-vector. Flies fed on a leishmanial lesion on the nose of a hamster were examined for infection at 0, 6, 12, 18, 24, 36, 48, and 60 hr and at approximately 24 hr intervals from day 3 to day 14 post-feeding. Infection rates, determined by light microscopy, were 47% (n = 258) in P. duboscqi and 5% (n = 162) in S. schwetzi. Transformation from amastigotes to "procyclic" promastigotes occurred in both species at 6-18 hr post-feeding. In P. duboscqi, the parasites multiplied rapidly and developed through as many as 10 forms, including at least 3 dividing-promastigote forms. Metacyclic promastigotes, the "infective" form, appeared at 6 days post-feeding, first in the region of the stomodeal valve, then in the pharynx, cibarium, and proboscis. In a single attempt 14 days post-feeding, a P. duboscqi transmitted L. major to a mouse by bite. In contrast, the parasites multiplied slowly in S. schwetzi, and did not develop beyond "procyclic" promastigotes. The parasites did not migrate anteriorly nor survive beyond 90 hr post-feeding, indicating that S. schwetzi is not a vector of L. major. Classical strategies for vector incrimination may be confounded by the isolation of non-infective early developmental forms of Leishmania from wild-caught non-vectors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0002-9637
pubmed:author
pubmed:issnType
Print
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
31-43
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Development of Leishmania major in Phlebotomus duboscqi and Sergentomyia schwetzi (Diptera: Psychodidae).
pubmed:affiliation
U.S. Army Medical Research Unit, Nairobi, Kenya.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, Non-P.H.S.