Evaluation of the MAP‐1B ELISA for Cowdriosis with Field Sera from Livestock in Zimbabwea

Mahan, Suman M.; Semu, S. M.; Peter, Trevor; Jongejan, Frans

doi:10.1111/j.1749-6632.1998.tb11057.x

Cited by 22 publications

(23 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Values for sera from experimentally infected cattle fell below 38 PP in the MAP1-B ELISA between 50 and 100 days postinoculation (38). A seroprevalence of 33% among nearly 400 bovine field sera tested by MAP1-B ELISA was reported from areas of Zimbabwe where heartwater is endemic, places where seroprevalence in goats exceeded 90% (24), and these values are quite similar to the overall seroprevalences of 31 and 83% in Ghanaian cattle and sheep found with the low MAP1-B ELISA cutoff. A similar seroprevalence of E. ruminantium of 31% was found with the MAP1-B ELISA in traditionally managed NЈDama cattle exposed to year-round Amblyomma variegatum challenge in Côte d'Ivoire (19).…”

Section: Discussionsupporting

confidence: 66%

“…It has been suggested that polymorphism among MAP1 antigens of different E. ruminantium isolates may affect the ability of the MAP1-B ELISA to detect heterologous antibodies (24); however, since the test successfully detected numerous seropositive adult Ghanaian sheep and first seroconversion in most of the Ghanaian calves, MAP1 polymorphism would not explain the negative results with subsequently collected sera from the same cattle. It has also been postulated that the MAP1-Bspecific antibody response may be down-regulated in cattle following exposure to E. ruminantium (24).…”

Section: Discussionmentioning

confidence: 83%

“…Serological tests utilizing recombinant antigens include an indirect ELISA based on a specific fragment of the E. ruminantium major antigenic protein (MAP1), the MAP1-B ELISA (38), and a competitive ELISA using recombinant MAP1 antigen and anti-MAP1 monoclonal antibody competitor (18). These have been shown to have increased specificity, though both antigens cross-react with antibodies to Ehrlichia chaffeensis, which infects deer and domestic goats in the southern United States (9), and sensitivity for bovine sera appears to be poor (24,33).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Detection by Two Enzyme-Linked Immunosorbent Assays of Antibodies toEhrlichia ruminantiumin Field Sera Collected from Sheep and Cattle in Ghana

Bell‐Sakyi

Koney

Dogbey

et al. 2003

Clin Vaccine Immunol

View full text Add to dashboard Cite

Two serological tests for detection of antibodies to Ehrlichia (previously Cowdria) ruminantium, the causative agent of heartwater, were compared by using field sera collected from sheep and cattle as part of serosurveys in Ghana. Sera selected as either negative or positive by a new polyclonal competitive enzyme-linked immunosorbent assay (PC-ELISA) were tested by the indirect MAP1-B ELISA. Cutoff values of 14 percent positivity (14 PP) for both ruminant species were obtained for the MAP1-B ELISA by using preseroconversion Ghanaian sera and were compared with previously recommended cutoff values of 29 PP for sheep and 38 PP for cattle. With the 14-PP cutoff, of 151 sheep sera which tested negative by PC-ELISA, 89% were also negative by MAP1-B ELISA, while of 419 sheep sera positive by PC-ELISA, 98% were also positive by MAP1-B ELISA. Of 261 bovine sera negative by PC-ELISA, 82% were also negative by MAP1-B ELISA. Of 511 bovine sera positive by PC-ELISA, only 47% were positive by MAP1-B ELISA; these included 168 sera collected from cattle following first seroconversion as detected by both tests, with 125 of these sera positive by PC-ELISA but only 59 and 5 positive by MAP1-B ELISA with the 14-and 38-PP cutoff levels, respectively. These results indicate that both assays are highly sensitive and specific for detection of E. ruminantium exposure in sheep but that the MAP1-B ELISA lacks sensitivity for postseroconversion bovine sera in comparison to the PC-ELISA. Both tests confirm E. ruminantium seroprevalence of at least 70% in Ghanaian sheep; levels of exposure among Amblyomma variegatum-infested Ghanaian cattle are likely to be higher than the seroprevalence value of 66% obtained with the PC-ELISA.Heartwater, or cowdriosis, caused by the rickettsia Ehrlichia (previously Cowdria) ruminantium (10) and transmitted by ticks of the genus Amblyomma, is an often fatal disease of susceptible domestic ruminants in sub-Saharan Africa and some Caribbean islands (7). Epidemiological surveys of E. ruminantium prevalence in areas of endemicity have been limited by the lack of suitably sensitive and specific serodiagnostic tests (15). Fluorescent antibody tests based on E. ruminantiuminfected mouse macrophages (11), neutrophils and bovine endothelial cell cultures (27), and immunoblotting assays (20, 25) lacked specificity (12,16,25) and were too labor-intensive for mass screening. Several enzyme-linked immunosorbent assay (ELISA) systems have been developed over the last decade, with progressive improvement in performance. Indirect ELISA protocols using crude elementary body-derived antigen (26, 34) and a monoclonal antibody-based competitive ELISA (17) resulted in cross-reactions with other ovine and bovine Ehrlichia species (12,16

show abstract

Section: Discussionsupporting

confidence: 66%

Section: Discussionmentioning

confidence: 83%

mentioning

confidence: 99%

See 1 more Smart Citation

Detection by Two Enzyme-Linked Immunosorbent Assays of Antibodies toEhrlichia ruminantiumin Field Sera Collected from Sheep and Cattle in Ghana

Bell‐Sakyi

Koney

Dogbey

et al. 2003

Clin Vaccine Immunol

View full text Add to dashboard Cite

show abstract

“…However, crossreactivity between Ehrlichia ruminantium antigens and antibodies to several Ehrlichia spp. has been observed (Jongejan, 1991;Mahan et al, 1998;OIE, 2002). Molecular diagnosis is presently the most reliable approach for detection of E. ruminantium carrier animals and ticks (Waghela et al, 1991;Mahan et al, 1992;Mutwakil et al, 2013).…”

Section: Discussionmentioning

confidence: 98%

Fatal Cowdriosis (Heartwater) and Trichurosis in a Camel Bull (Camelus dromedarius): a case report

Mohammed¹,

Samuel²,

Salisu³

et al. 2017

AJVS

View full text Add to dashboard Cite

Key words:Camel, Heartwater, Trichurosis, whipworms, Ehrlichia ruminantium, Nigeria A 5 year old male camel was reported dead in an institutional farm, and a routine postmortem was conducted on it. Adult worms were found in the lumen of the large intestines and segments of all intestines were sent to the parasitology laboratory for helminth identification. Rectal contents were also sent to the laboratory for oocyst screening. Lung and brain samples were also sent to the parasitology laboratory based on history. The result from the parasitology laboratory confirmed a helminth infection known as trichurosis and heartwater infection was also confirmed from presence of purple colonies of Ehrlichia ruminantium on the endothelium of capillaries close to the nuclei. Although it was hard to establish which of the infections caused the death of the animal but it is noteworthy that this case confirms natural susceptibility of the camel to both diseases and is capable of causing mortality in camels.

show abstract

“…carried by ticks in this region 15 . These improvements imply that serological surveys on goats should have more credibility than in the past.…”

Section: Discussionmentioning

confidence: 99%

Ixodid ticks on indigenous goats owned by small-scale farmers in four communal grazing areas in South Africa

Bryson¹,

Tice²,

Horak³

et al. 2002

J. S. Afr. Vet. Assoc.

View full text Add to dashboard Cite

Indigenous goats belonging to small-scale farmers in 4 communal grazing areas in South Africa were sampled for ixodid ticks during the period September 1991 to May 1993. Three of these areas were in the North West Province (Rietgat, Madinyane and Bethany), and one in Mpumalanga Province (Geluk). No tick control was practised unless requested by the owners. Seven ixodid tick species, of which the majority were immature ticks, were collected from the goats in North West Province. Amblyomma hebraeum was the most numerous of these, followed by Rhipicephalus evertsi evertsi and Rhipicephalus appendiculatus. Substantially more ticks were collected from goats at Rietgat than at the Madinyane and Bethany grazing areas. Five tick species were collected at Geluk and R. evertsi evertsi comprised more than 95 % of the total population. At Rietgat and Geluk A. hebraeum nymphs were present on goats throughout the year, while most R appendiculatus nymphs were collected during September and October 1991 and most adults during January and February 1992. At both Rietgat and Geluk most immature R. evertsi evertsi were collected from spring to late summer, while adults were present throughout the year

show abstract

Evaluation of the MAP‐1B ELISA for Cowdriosis with Field Sera from Livestock in Zimbabwe^a

Cited by 22 publications

References 8 publications

Detection by Two Enzyme-Linked Immunosorbent Assays of Antibodies toEhrlichia ruminantiumin Field Sera Collected from Sheep and Cattle in Ghana

Detection by Two Enzyme-Linked Immunosorbent Assays of Antibodies toEhrlichia ruminantiumin Field Sera Collected from Sheep and Cattle in Ghana

Fatal Cowdriosis (Heartwater) and Trichurosis in a Camel Bull (Camelus dromedarius): a case report

Ixodid ticks on indigenous goats owned by small-scale farmers in four communal grazing areas in South Africa

Contact Info

Product

Resources

About