Elimination of Onchocerciasis from Mexico

Rodríguez‐Pérez, Mario A.; Fernández‐Santos, Nadia A.; Orozco-Algarra, María E.; Rodríguez-Atanacio, José A.; Domínguez-Vázquez, Alfredo; Rodríguez-Morales, Kristel B.; Real-Najarro, Olga; Prado-Velasco, Francisco Gibert; Cupp, Eddie W.; Richards, Frank O.; Hassan, Hassan K.; González-Roldán, Jesús Felipe; Kuri‐Morales, Pablo; Unnasch, Thomas R.

doi:10.1371/journal.pntd.0003922

Cited by 55 publications

(45 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…WHO has verified the elimination of onchocerciasis in four of the six countries where the disease was formerly endemic. In 2013, Colombia was the first country in the world where elimination of onchocerciasis was verified by WHO [26], followed by Ecuador in 2014 [27] and Mexico in 2015 [28, 29]. Onchocerciasis was also eliminated from Guatemala in 2015 [30], verified by the WHO in 2016 [31].…”

Section: Discussionmentioning

confidence: 99%

Elimination of onchocerciasis from Colombia: first proof of concept of river blindness elimination in the world

et al. 2018

View full text Add to dashboard Cite

BackgroundOnchocerciasis is a chronic parasitic infection originally endemic in 13 discrete regional foci distributed among six countries of Latin America (Brazil, Colombia, Ecuador, Guatemala, Mexico and Venezuela). In Colombia, this disease was discovered in 1965 in the Pacific Coast of the country. The National Onchocerciasis Elimination Program was established in 1993 with the aim of eliminating disease morbidity and infection transmission. In 2013, the World Health Organization (WHO) verified Colombia as free of onchocerciasis, becoming the first country in the world to reach such a goal. This report provides the empirical evidence of the elimination of Onchocerca volvulus transmission by Simulium exiguum (s.l.) after 12 years of 6-monthly mass drug administration of Mectizan® (ivermectin) to all the eligible residents living in this endemic area.MethodsFrom 1996 onwards, a biannual community-based mass ivermectin administration programme was implemented, complemented by health education and community participation. In-depth parasitological, serological and entomological surveys were conducted periodically between 1998 and 2007 to evaluate the impact of ivermectin treatment according to the 2001 WHO guidelines. When the interruption of parasite transmission was demonstrated, the drug distribution ceased and a three-year post-treatment surveillance (PTS) period (2008–2010) was initiated.ResultsAfter 23 rounds of treatment, parasitological and ophthalmological assessments showed absence of microfilariae in skin and anterior chamber of the eyes. Serological tests proved lack of antibodies against O. volvulus in children under 10 years-old. A total of 10,500 S. exiguum flies tested by PCR had no L3 infection (infectivity rate = 0.0095%; 95% CI: 0.0029–0.049) during 2004, indicating interruption of parasite transmission. However, biannual ivermectin treatments continued until 2007 followed by a 3-year PTS period at the end of which 13,481 flies were analyzed and no infective flies were found (infectivity rate = 0%; 95% CI: 0.0–0.014).ConclusionsThese results fulfilled the WHO criteria for onchocerciasis elimination. Consequently, in 2013 Colombia was verified as free of onchocerciasis, demonstrating that elimination of this neglected tropical disease is an achievable goal and paving the way for an elimination agenda to be followed by other endemic countries in Latin America and Africa.

show abstract

Section: Discussionmentioning

confidence: 99%

Elimination of onchocerciasis from Colombia: first proof of concept of river blindness elimination in the world

et al. 2018

View full text Add to dashboard Cite

show abstract

“…While this drug has been administrated twice or four times a year in the small and well-delineated endemic communities of the Americas, single doses have been given yearly in the much larger foci in African endemic countries [14, 15]. As a consequence, the programmes in the Americas are highly successful and are attaining the onchocerciasis elimination point [16–20], while this disease remains a public health problem in Africa. Nevertheless, new evidence points exist towards the possibility of successful elimination of river blindness in Africa using ivermectin solely [21, 22].…”

Section: Introductionmentioning

confidence: 99%

Still mesoendemic onchocerciasis in two Cameroonian community-directed treatment with ivermectin projects despite more than 15 years of mass treatment

et al. 2016

View full text Add to dashboard Cite

BackgroundAfter more than a decade of community-directed treatment with ivermectin (CDTI) in Centre and Littoral Regions of Cameroon, onchocerciasis endemicity was still high in some communities according to the 2011 epidemiological evaluations. Some corrective measures were undertaken to improve the CDTI process and therefore reduce the burden of the disease. The objective of the present study was to assess the progress made towards the elimination of onchocerciasis in the Centre 1 and Littoral 2 CDTI projects where the worst performances were found in 2011. To this end, a cross-sectional survey was conducted in April 2015 in eight communities in two health districts (HD), Bafia in Centre 1 and Yabassi in Littoral 2, chosen because assessed at baseline and in 2011. All volunteers living for at least five years in the community, aged five years or more, underwent clinical and parasitological examinations. Individual compliance to ivermectin treatment was also assessed. Analyses of data were weighted proportionally to age and gender distribution in the population.ResultsIn the Bafia and Yabassi HD, 514 and 242 individuals were examined with a mean age of 35.1 (standard deviation, SD: 20.7) and 44.6 (SD: 16.3) years, respectively. In the Bafia HD, the weighted prevalences varied from 24.4 to 57.0 % for microfilaridermia and from 3.6 to 37.4 % for nodule presence across the surveyed communities. The community microfilarial load (CMFL), expressed in microfilariae/skin snip (mf/ss), significantly dropped from 20.84–114.50 mf/ss in 1991 to 0.31–1.62 mf/ss in 2015 in all the surveyed communities. In the Yabassi HD, the weighted prevalences varied from 12.3 to 59.3 % for microfilaridermia and from 1.5 to 3.7 % for nodule presence across the surveyed communities, while a significant drop was observed in CMFL, from 20.40–28.50 mf/ss in 1999 to 0.48–1.74 mf/ss in 2015. The 2014 weighted therapeutic coverage of participants varied from 65.8 % (95 % CI: 58.4–73.2) in Yabassi HD, to 68.0 % (95 % CI: 63.3–72.7) in Bafia HD, with important variations among communities.ConclusionsAfter more than 15 years of CDTI, onchocerciasis is still mesoendemic in the surveyed communities. Further studies targeting therapeutic coverage, socio-anthropological considerations of CDTI implementation and entomological studies would bring more insights to the persistence of the disease as observed in the present study.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-016-1868-8) contains supplementary material, which is available to authorized users.

show abstract

“…Ecuador and Mexico are examples of countries in which the disease has actually been eliminated (18,19)…”

Section: The Value Of Flexible Clinical Objectivesmentioning

confidence: 99%

Lessons from the History of Ivermectin and Other Antiparasitic Agents

Campbell

2016

Annu. Rev. Anim. Biosci.

View full text Add to dashboard Cite

The twentieth century's arsenal of chemical anthelmintics brought manifold improvement in human health and, more abundantly, in animal health. The benefits were not only in health per se but also in agricultural economics, livestock management, and the overall production of food and fiber to support expanding human populations. Nevertheless, there remains (due in large part to drug resistance and paucity of available vaccines) a great need for new means of controlling disease caused by parasitic worms. Prudence should persuade us to look to our past for lessons that might help in our quest for new drugs. The lessons suggested here derive from the history of ivermectin and other anthelmintics. They deal with the means of finding substances with useful antiparasitic activity and with alternative approaches to drug discovery.

show abstract

Elimination of Onchocerciasis from Mexico

Cited by 55 publications

References 32 publications

Elimination of onchocerciasis from Colombia: first proof of concept of river blindness elimination in the world

Elimination of onchocerciasis from Colombia: first proof of concept of river blindness elimination in the world

Still mesoendemic onchocerciasis in two Cameroonian community-directed treatment with ivermectin projects despite more than 15 years of mass treatment

Lessons from the History of Ivermectin and Other Antiparasitic Agents

Contact Info

Product

Resources

About