Elimination of Onchocerciasis from Mexico.
BACKGROUND:Mexico is one of the six countries formerly endemic for onchocerciasis in Latin America. Transmission has been interrupted in the three endemic foci of that country and mass drug distribution has ceased. Three years after mass drug distribution ended, post-treatment surveillance (PTS) sur...
| Main Authors: | , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2015-01-01
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| Series: | PLoS Neglected Tropical Diseases |
| Online Access: | http://europepmc.org/articles/PMC4498594?pdf=render |
| _version_ | 1818133604467736576 |
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| author | Mario A Rodríguez-Pérez Nadia A Fernández-Santos María E Orozco-Algarra José A Rodríguez-Atanacio Alfredo Domínguez-Vázquez Kristel B Rodríguez-Morales Olga Real-Najarro Francisco G Prado-Velasco Eddie W Cupp Frank O Richards Hassan K Hassan Jesús F González-Roldán Pablo A Kuri-Morales Thomas R Unnasch |
| author_facet | Mario A Rodríguez-Pérez Nadia A Fernández-Santos María E Orozco-Algarra José A Rodríguez-Atanacio Alfredo Domínguez-Vázquez Kristel B Rodríguez-Morales Olga Real-Najarro Francisco G Prado-Velasco Eddie W Cupp Frank O Richards Hassan K Hassan Jesús F González-Roldán Pablo A Kuri-Morales Thomas R Unnasch |
| author_sort | Mario A Rodríguez-Pérez |
| collection | DOAJ |
| description | BACKGROUND:Mexico is one of the six countries formerly endemic for onchocerciasis in Latin America. Transmission has been interrupted in the three endemic foci of that country and mass drug distribution has ceased. Three years after mass drug distribution ended, post-treatment surveillance (PTS) surveys were undertaken which employed entomological indicators to check for transmission recrudescence. METHODOLOGY/PRINCIPAL FINDINGS:In-depth entomologic assessments were performed in 18 communities in the three endemic foci of Mexico. None of the 108,212 Simulium ochraceum s.l. collected from the three foci were found to contain parasite DNA when tested by polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA), resulting in a maximum upper bound of the 95% confidence interval (95%-ULCI) of the infective rate in the vectors of 0.035/2,000 flies examined. This is an order of magnitude below the threshold of a 95%-ULCI of less than one infective fly per 2,000 flies tested, the current entomological criterion for interruption of transmission developed by the international community. The point estimate of seasonal transmission potential (STP) was zero, and the upper bound of the 95% confidence interval for the STP ranged from 1.2 to 1.7 L3/person/season in the different foci. This value is below all previous estimates for the minimum transmission potential required to maintain the parasite population. CONCLUSIONS/SIGNIFICANCE:The results from the in-depth entomological post treatment surveillance surveys strongly suggest that transmission has not resumed in the three foci of Mexico during the three years since the last distribution of ivermectin occurred; it was concluded that transmission remains undetectable without intervention, and Onchocerca volvulus has been eliminated from Mexico. |
| first_indexed | 2024-12-11T08:55:22Z |
| format | Article |
| id | doaj.art-75453c028ccd4eecb26a8d70f2632a60 |
| institution | Directory Open Access Journal |
| issn | 1935-2727 1935-2735 |
| language | English |
| last_indexed | 2024-12-11T08:55:22Z |
| publishDate | 2015-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Neglected Tropical Diseases |
| spelling | doaj.art-75453c028ccd4eecb26a8d70f2632a602022-12-22T01:13:54ZengPublic Library of Science (PLoS)PLoS Neglected Tropical Diseases1935-27271935-27352015-01-0197e000392210.1371/journal.pntd.0003922Elimination of Onchocerciasis from Mexico.Mario A Rodríguez-PérezNadia A Fernández-SantosMaría E Orozco-AlgarraJosé A Rodríguez-AtanacioAlfredo Domínguez-VázquezKristel B Rodríguez-MoralesOlga Real-NajarroFrancisco G Prado-VelascoEddie W CuppFrank O RichardsHassan K HassanJesús F González-RoldánPablo A Kuri-MoralesThomas R UnnaschBACKGROUND:Mexico is one of the six countries formerly endemic for onchocerciasis in Latin America. Transmission has been interrupted in the three endemic foci of that country and mass drug distribution has ceased. Three years after mass drug distribution ended, post-treatment surveillance (PTS) surveys were undertaken which employed entomological indicators to check for transmission recrudescence. METHODOLOGY/PRINCIPAL FINDINGS:In-depth entomologic assessments were performed in 18 communities in the three endemic foci of Mexico. None of the 108,212 Simulium ochraceum s.l. collected from the three foci were found to contain parasite DNA when tested by polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA), resulting in a maximum upper bound of the 95% confidence interval (95%-ULCI) of the infective rate in the vectors of 0.035/2,000 flies examined. This is an order of magnitude below the threshold of a 95%-ULCI of less than one infective fly per 2,000 flies tested, the current entomological criterion for interruption of transmission developed by the international community. The point estimate of seasonal transmission potential (STP) was zero, and the upper bound of the 95% confidence interval for the STP ranged from 1.2 to 1.7 L3/person/season in the different foci. This value is below all previous estimates for the minimum transmission potential required to maintain the parasite population. CONCLUSIONS/SIGNIFICANCE:The results from the in-depth entomological post treatment surveillance surveys strongly suggest that transmission has not resumed in the three foci of Mexico during the three years since the last distribution of ivermectin occurred; it was concluded that transmission remains undetectable without intervention, and Onchocerca volvulus has been eliminated from Mexico.http://europepmc.org/articles/PMC4498594?pdf=render |
| spellingShingle | Mario A Rodríguez-Pérez Nadia A Fernández-Santos María E Orozco-Algarra José A Rodríguez-Atanacio Alfredo Domínguez-Vázquez Kristel B Rodríguez-Morales Olga Real-Najarro Francisco G Prado-Velasco Eddie W Cupp Frank O Richards Hassan K Hassan Jesús F González-Roldán Pablo A Kuri-Morales Thomas R Unnasch Elimination of Onchocerciasis from Mexico. PLoS Neglected Tropical Diseases |
| title | Elimination of Onchocerciasis from Mexico. |
| title_full | Elimination of Onchocerciasis from Mexico. |
| title_fullStr | Elimination of Onchocerciasis from Mexico. |
| title_full_unstemmed | Elimination of Onchocerciasis from Mexico. |
| title_short | Elimination of Onchocerciasis from Mexico. |
| title_sort | elimination of onchocerciasis from mexico |
| url | http://europepmc.org/articles/PMC4498594?pdf=render |
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