Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Bedbugs”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMedDate not supplied

Changes in the relative frequency of occurrence of infestations of two sympatric species of bedbug in northern Natal and KwaZulu, South Africa.

Between 1983 and 1988 the frequency of Cimex hemipterus infestations relative to C. lectularius increased near the Mozambique border and around main roads in the Nkundusi-Mfekayi area of South Africa (28 degrees 15'S; 30 degrees 23' E). In areas where both species were common, the observed number of doubly-infested huts equalled the expected. A hut infested by both bedbug species showed a significant change to a higher proportion of C. hemipterus in the adult population over 2 months. The general increase in C. hemipterus is thought to be due to the large influx of migrants into South Africa in recent years.

Animals↗
PubMed1997

Phylogenetic characterization of two transovarially transmitted endosymbionts of the bedbug Cimex lectularius (Heteroptera:Cimicidae).

Two different inherited bacterial symbionts from ovary tissue of the bedbug Cimex lectularius were characterized by gene amplification and sequencing analysis of their 16S rDNA gene. The first bacterium belongs to the Wolbachia subgroup of the alpha-Proteobacteria, the second is a member of the gamma-subdivision, and is closely related to the bacterial parasite of the leafhopper Euscelidius variegatus (BEV) which was shown to be capable of transovarial transmission. The high similarity (> 97%) between the C. lectularius symbiont and BEV indicates that these two microorganisms belong to the same lineage and share the ability to invade distant insect hosts to fulfill their symbiotic functions and to establish transovarial transmission to future generations.

Animals↗
PubMed1987

A reovirus from the bedbug, Cimex lectularius.

Large numbers of virus particles were identified by electron microscopy in the epithelial cells of the ventriculus of the bedbug, Cimex lectularius. The morphology of the virus particles and the presence of a segmented double-stranded RNA genome imply that this isolate should be included in the Reoviridae.

Animals↗
PubMed1995

A salivary nitrophorin (nitric-oxide-carrying hemoprotein) in the bedbug Cimex lectularius.

Salivary gland homogenate of the bedbug Cimex lectularius caused vasodilation of the preconstricted rabbit aortic ring in the absence of endothelium. Vasodilation was augmented in the presence of superoxide dismutase and inhibited in the presence of Methylene Blue. Utilization of the Griess reaction indicated the presence of reactive nitrogen equivalents of the order of 337 +/- 57 pg equivalent NO2- per pair of salivary glands (mean +/- S.E.M.; N = 3). Salivary gland homogenates have a nitrosyl-hemoprotein that releases nitric oxide in a pH-dependent manner. The fraction containing the NO-carrying hemoprotein, when separated by HPLC, caused vasodilation of the preconstricted rabbit aortic strip. Furthermore, the presence of a nitrosyl-hemoprotein in Cimex lectularius salivary gland was verified by electron paramagnetic resonance spectroscopy. It is proposed that, as in the case of Rhodnius prolixus (Triatominae), Cimex lectularius salivary glands contain a hemoprotein (nitrophorin) that carries NO from the glands to the host tissues. However, because Cimex lectularius and Rhodnius prolixus belong to different hemipteran families (Cimicidae and Reduvidae) and evolved independently to blood feeding, Cimex lectularius and Rhodnius prolixus nitrophorin may be a case of convergent evolution.

Animals↗
PubMed1979

Transmission experiments with hepatitis B surface antigen and the common bedbug (Cimex lectularius L).

Hepatitis B surface antigen (HBsAg)-positive blood meals were fed to a colony of the common bedbug (Cimex lectularius L) in a series of 5 experiments. Antigen persisted in the bugs for at least 7 1/2 weeks, but was undetectable after 18 weeks. Trans-stadial transmission was demonstrated through one moult only, and transovarial transmission did not occur. Antigen was successfully transmitted by adult bugs into 3 out of 35 canisters of HBsAg-negative blood. Antibody of HBsAg was detected in the serum from a rabbit on which HBsAg-positive adult bugs had fed as well as in the serum of 2 out of 10 guinea-pigs on which HBsAg-positive 4th and 5th nymphal instars had fed. The results as a whole indicate that biological multiplication and biological transmission do not occur in C. lectularius, but mechanical transmission has been demonstrated. This is probably an important means of hepatitis B virus transmission among humans in South Africa.

Animals↗
PubMed1978

Infection of the common bedbug (Cimex lectularius L) with hepatitis B virus in South Africa.

A total of 1 368 bedbugs of the species Cimex lectularius L were collected mainly from huts in villages or on farms at 6 localities in the northern Transvaal. They were tested in pools of 10 for the presence of hepatitis B surface antigen (HBsAg). None of 20 pools from Pietersburg was HBsAg-positive, but 32 out of 120 pools from the 5 other localities were HBsAg-positive. Estimated infection rates per 1 000 bugs were 17,1 (Messina), 24,9 (Waterpoort), 28,4 (Letaba), 54,5 (Potgietersrus) and 67,0 (Louis Trichardt), with an overall rate of 30,6. Seventeen out of 57 pools of the engorged bugs (infection rate 34,8) and 14 out of 62 pools of the unengorged bugs (infection rate 25,3) were HBsAg-positive. These very high infection rates, even in unengorged bugs, suggest that C. lectularius could be a vector of hepatitis B virus in the Transvaal, and that the varying degrees of infestation could explain the markedly different HBsAg-positive frequencies previously shown in sera collected from different population groups in that province.

Animals↗
PubMed1983

The mechanical transmission of hepatitis B virus by the common bedbug (Cimex lectularius L.) in South Africa.

Tests for both hepatitis B surface antigen (HBsAg) and hepatitis e antigen (HBeAg) were carried out on wild-caught and laboratory-colonized bedbugs (Cimex lectularius L.), the latter after hepatitis B virus (HBV)-positive blood-meals. Positivity for both antigens was interpreted as an indication of HBV infectivity. Of 22 pools in which were tested 211 bugs collected in the northern Transvaal, 18 were HBsAg-positive and 17 HBeAg-positive, with estimated infection rates of 156,7 and 137,7 per 1000 bugs respectively. Passage of HBV in bugs, allowing an extrinsic incubation period of 57-69 days, resulted in 19 out of 25 bugs being positive for HBsAg after the first passage; only a small number of these were positive for HBeAg. After the second passage all bugs tested were HBsAg-negative, showing that the virus had disappeared. Tests on the salivary glands and carcass of each bug at intervals up to 31 days after an infective meal showed a positivity rate of 98% (HBsAg) and 17% (HBeAg) for carcasses and 20% (HBsAg) and 0% (HBeAg) for salivary glands. Attempts to detect HBV particles in the salivary glands by electron microscopy failed. Bugs were shown to continue to excrete HBsAg in their faeces up to the 42nd day, and both HBsAg and HBeAg together up to the 30th day. HBsAg particles were only detected by electron microscopy in faeces harvested on the 10th day. The results as a whole indicate that no biological multiplication of virus occurs in C. lectularius but that mechanical transmission from insects to man could occur by: (i) contamination of a person when crushing infective bugs; (ii) contamination from infected faeces; and (iii) infection by bite due to regurgitation or interrupted feeding.

Animals↗
PubMed1995

Comparative activity of three repellents against bedbugs Cimex hemipterus (Fabr.).

Comparative activity of three repellents viz., diethyl-m-toluamide (DEET), diethyl phenyl-acetamide (DEPA) and dimethylphthalate (DMP) against bedbugs Cimex hemipterus (Fabr) was studied by applying repellent solution on the shaven skin of rabbits. DEET (Tech. grade) 20mgai/cm2 exhibited 93 and 83 per cent repellency after 2 and 8 h respectively, while DEPA (Tech. grade) at this concentration exhibited 90 and 71 per cent repellency. DEET and DEPA at 75 per cent concentration (15mgai/cm2) showed 85 and 78 per cent repellency up to 2 h and 52 and 42 per cent repellency 6 h after treatment respectively. The repellent activity was also found to be concentration and time of treatment dependent in respect of DEET and DEPA. DMP (Tech. grade) did not show any appreciable repellent activity at any concentration tested. Further, the blood intake by C. hemipterus following treatment with various concentrations of repellents was found to decrease with increase in the concentration of repellents.

Animals↗