Journal Article > ResearchFull Text
Sci Rep. 2016 October 24; Volume 6; 35742.; DOI:10.1038/srep35742
Iyer AS, Ryan ET, Martin S, Legros D, Lessler J, et al.
Sci Rep. 2016 October 24; Volume 6; 35742.; DOI:10.1038/srep35742
Despite recent large-scale cholera outbreaks, little is known about the immunogenicity of oral cholera vaccines (OCV) in African populations, particularly among those at highest cholera risk. During a 2015 preemptive OCV campaign among internally displaced persons in South Sudan, a year after a large cholera outbreak, we enrolled 37 young children (1-5 years old), 67 older children (6-17 years old) and 101 adults (≥18 years old), who received two doses of OCV (Shanchol) spaced approximately 3 weeks apart. Cholera-specific antibody responses were determined at days 0, 21 and 35 post-immunization. High baseline vibriocidal titers (>80) were observed in 21% of the participants, suggesting recent cholera exposure or vaccination. Among those with titers ≤80, 90% young children, 73% older children and 72% adults seroconverted (≥4 fold titer rise) after the 1(st) OCV dose; with no additional seroconversion after the 2(nd) dose. Post-vaccination immunological endpoints did not differ across age groups. Our results indicate Shanchol was immunogenic in this vulnerable population and that a single dose alone may be sufficient to achieve similar short-term immunological responses to the currently licensed two-dose regimen. While we found no evidence of differential response by age, further immunologic and epidemiologic studies are needed.
Journal Article > ResearchFull Text
Vaccine. 2006 May 29; Volume 24 (Issue 22); 4890-4895.; DOI:10.1016/j.vaccine.2005.10.006
Cavailler P, Perroud V, Mcchesney M, Ampuero S, Guerin PJ, et al.
Vaccine. 2006 May 29; Volume 24 (Issue 22); 4890-4895.; DOI:10.1016/j.vaccine.2005.10.006
We conducted a study to assess the feasibility and the potential vaccine coverage of a mass vaccination campaign using a two-dose oral cholera vaccine in an urban endemic neighbourhood of Beira, Mozambique. The campaign was conducted from December 2003 to January 2004. Overall 98,152 doses were administered, and vaccine coverage of the target population was 58.6% and 53.6% for the first and second rounds, respectively. The direct cost of the campaign, which excludes the price of the vaccine, amounted to slightly over 90,000 dollars, resulting in the cost per fully vaccinated person of 2.09 dollars, which is relatively high. However, in endemic settings where outbreaks are likely to occur, integrating cholera vaccination into the routine activities of the public health system could reduce such costs.
Journal Article > ResearchFull Text
Am J Trop Med Hyg. 2004 April 1; Volume 70 (Issue 4); 390-394.
Hutin Y, Legros D, Owini V, Brown V, Lee EC, et al.
Am J Trop Med Hyg. 2004 April 1; Volume 70 (Issue 4); 390-394.
We estimated the pre-intervention prevalence of Trypanosoma brucei gambiense (Tbg) trypanosomiasis using the lot quality assurance sampling (LQAS) methods in 14 parishes of Terego County in northern Uganda. A total of 826 participants were included in the survey sample in 1996. The prevalence of laboratory confirmed Tbg trypanosomiasis adjusted for parish population sizes was 2.2% (95% confidence interval =1.1-3.2). This estimate was consistent with the 1.1% period prevalence calculated on the basis of cases identified through passive and active screening in 1996-1999. Ranking of parishes in four categories according to LQAS analysis of the 1996 survey predicted the prevalences observed during the first round of active screening in the population in 1997-1998 (P < 0.0001, by chi-square test). Overall prevalence and ranking of parishes obtained with LQAS were validated by the results of the population screening, suggesting that these survey methods may be useful in the pre-intervention phase of sleeping sickness control programs.
Journal Article > ResearchFull Text
Bull Soc Pathol Exot. 1999 July 1
Legros D, Fournier C, Gastellu-Etchegorry M, Maiso F, Szumilin E
Bull Soc Pathol Exot. 1999 July 1
The failure rate of melarsoprol after treatment of late stage cases of Human African Trypanosomiasis (HAT) is usually under 7%, even though the drug has been used for such treatment over the past 50 years. We report a melarsoprol treatment failure rate of 26.9% among 428 patients treated in Northern Uganda. Whatever its origin, this observation, the first documented in a HAT focus, is alarming, particularly since no second line trypanocidal drug is actually available for the treatment of late stage HAT. We believe that the current worrisome situation of HAT in several African countries and the risk of emergence of other foci of resistance, argue in favour of a greater attention on the part of the scientific community and the pharmaceutical companies being paid to this problem.
Journal Article > ResearchFull Text
Lancet. 2008 April 14; Volume 366 (Issue 9482); DOI:10.1016/S0140-6736(05)66792-X
Nathan N, Borel T, Djibo A, Evans D, Djibo S, et al.
Lancet. 2008 April 14; Volume 366 (Issue 9482); DOI:10.1016/S0140-6736(05)66792-X
BACKGROUND: In sub-Saharan Africa in the 1990s, more than 600,000 people had epidemic meningococcal meningitis, of whom 10% died. The current recommended treatment by WHO is short-course long-acting oily chloramphenicol. Continuation of the production of this drug is uncertain, so simple alternatives need to be found. We assessed whether the efficacy of single-dose treatment of ceftriaxone was non-inferior to that of oily chloramphenicol for epidemic meningococcal meningitis. METHODS: In 2003, we undertook a randomised, open-label, non-inferiority trial in nine health-care facilities in Niger. Participants with suspected disease who were older than 2 months were randomly assigned to receive either chloramphenicol or ceftriaxone. Primary outcome was treatment failure (defined as death or clinical failure) at 72 h, measured with intention-to-treat and per-protocol analyses. FINDINGS: Of 510 individuals with suspected disease, 247 received ceftriaxone, 256 received chloramphenicol, and seven were lost to follow-up. The treatment failure rate at 72 h for the intention-to-treat analysis was 9% (22 patients) for both drug groups (risk difference 0.3%, 90% CI -3.8 to 4.5). Case fatality rates and clinical failure rates were equivalent in both treatment groups (14 [6%] ceftriaxone vs 12 [5%] chloramphenicol). Results were also similar for both treatment groups in individuals with confirmed meningitis caused by Neisseria meningitidis. No adverse side-effects were reported. INTERPRETATION: Single-dose ceftriaxone provides an alternative treatment for epidemic meningococcal meningitis--its efficacy, ease of use, and low cost favour its use. National and international health partners should consider ceftriaxone as an alternative first-line treatment to chloramphenicol for epidemic meningococcal meningitis.
Journal Article > ResearchFull Text
Ann Trop Med Parasitol. 2002 September 1; Volume 96 (Issue 6); DOI:10.1179/000349802125001654
Guthmann JP, Kasparian S, Phetsouvanh R, Nathan N, Garcia MG, et al.
Ann Trop Med Parasitol. 2002 September 1; Volume 96 (Issue 6); DOI:10.1179/000349802125001654
To assess the local efficacy of chloroquine for the treatment of acute, uncomplicated, Plasmodium falciparum malaria, children and adults from Sekong province (an area of Laos with a low intensity of transmission) were tested in a 28-day, in-vivo study. Complete data were collected from 88 of the 102 subjects enrolled between October 1999 and September 2000. After genotypic analysis to distinguish recrudescing infections from re-infections, 35 (39.7%, with a 95% confidence interval of 29.5%-50.7%) of these 88 patients were considered treatment failures. These results seriously question the use of chloroquine as the first-line treatment for P. falciparum malaria in the study area.
Journal Article > CommentaryFull Text
Lancet. 2003 July 5; Volume 362 (Issue 9377); 74-75.; DOI:10.1016/S0140-6736(03)13813-5
Checchi F, Elder G, Schäfer M, Drouhin E, Legros D
Lancet. 2003 July 5; Volume 362 (Issue 9377); 74-75.; DOI:10.1016/S0140-6736(03)13813-5
Journal Article > CommentaryFull Text
Lancet. 2016 January 2; Volume 387 (Issue 10013); DOI:10.1016/S0140-6736(15)01294-5
Azman AS, Ivers LI, Legros D, Luquero FJ, Mintz ED
Lancet. 2016 January 2; Volume 387 (Issue 10013); DOI:10.1016/S0140-6736(15)01294-5
Journal Article > ReviewFull Text
PLOS One. 2020 January 8; Volume 15 (Issue 1); DOI:10.1371/journal.pone.0226549
D Mello Guyett L, Gallandat K, Van der Bergh R, Taylor DL, Bulit G, et al.
PLOS One. 2020 January 8; Volume 15 (Issue 1); DOI:10.1371/journal.pone.0226549
INTRODUCTION:
Cholera remains a frequent cause of outbreaks globally, particularly in areas with inadequate water, sanitation and hygiene (WASH) services. Cholera is spread through faecal-oral routes, and studies demonstrate that ingestion of Vibrio cholerae occurs from consuming contaminated food and water, contact with cholera cases and transmission from contaminated environmental point sources. WASH guidelines recommending interventions for the prevention and control of cholera are numerous and vary considerably in their recommendations. To date, there has been no review of practice guidelines used in cholera prevention and control programmes.
METHODS:
We systematically searched international agency websites to identify WASH intervention guidelines used in cholera programmes in endemic and epidemic settings. Recommendations listed in the guidelines were extracted, categorised and analysed. Analysis was based on consistency, concordance and recommendations were classified on the basis of whether the interventions targeted within-household or community-level transmission.
RESULTS:
Eight international guidelines were included in this review: three by non-governmental organisations (NGOs), one from a non-profit organisation (NPO), three from multilateral organisations and one from a research institution. There were 95 distinct recommendations identified, and concordance among guidelines was poor to fair. All categories of WASH interventions were featured in the guidelines. The majority of recommendations targeted community-level transmission (45%), 35% targeted within-household transmission and 20% both.
CONCLUSIONS:
Recent evidence suggests that interventions for effective cholera control and response to epidemics should focus on case-centred approaches and within-household transmission. Guidelines did consistently propose interventions targeting transmission within households. However, the majority of recommendations listed in guidelines targeted community-level transmission and tended to be more focused on preventing contamination of the environment by cases or recurrent outbreaks, and the level of service required to interrupt community-level transmission was often not specified. The guidelines in current use were varied and interpretation may be difficult when conflicting recommendations are provided. Future editions of guidelines should reflect on the inclusion of evidence-based approaches, cholera transmission models and resource-efficient strategies.
Cholera remains a frequent cause of outbreaks globally, particularly in areas with inadequate water, sanitation and hygiene (WASH) services. Cholera is spread through faecal-oral routes, and studies demonstrate that ingestion of Vibrio cholerae occurs from consuming contaminated food and water, contact with cholera cases and transmission from contaminated environmental point sources. WASH guidelines recommending interventions for the prevention and control of cholera are numerous and vary considerably in their recommendations. To date, there has been no review of practice guidelines used in cholera prevention and control programmes.
METHODS:
We systematically searched international agency websites to identify WASH intervention guidelines used in cholera programmes in endemic and epidemic settings. Recommendations listed in the guidelines were extracted, categorised and analysed. Analysis was based on consistency, concordance and recommendations were classified on the basis of whether the interventions targeted within-household or community-level transmission.
RESULTS:
Eight international guidelines were included in this review: three by non-governmental organisations (NGOs), one from a non-profit organisation (NPO), three from multilateral organisations and one from a research institution. There were 95 distinct recommendations identified, and concordance among guidelines was poor to fair. All categories of WASH interventions were featured in the guidelines. The majority of recommendations targeted community-level transmission (45%), 35% targeted within-household transmission and 20% both.
CONCLUSIONS:
Recent evidence suggests that interventions for effective cholera control and response to epidemics should focus on case-centred approaches and within-household transmission. Guidelines did consistently propose interventions targeting transmission within households. However, the majority of recommendations listed in guidelines targeted community-level transmission and tended to be more focused on preventing contamination of the environment by cases or recurrent outbreaks, and the level of service required to interrupt community-level transmission was often not specified. The guidelines in current use were varied and interpretation may be difficult when conflicting recommendations are provided. Future editions of guidelines should reflect on the inclusion of evidence-based approaches, cholera transmission models and resource-efficient strategies.
Journal Article > ResearchFull Text
PLOS Med. 2008 August 5; Volume 5 (Issue 8); DOI:10.1371/journal.pmed.0050169
Guthmann JP, Checchi F, van den Broek IVF, Balkan S, Van Herp M, et al.
PLOS Med. 2008 August 5; Volume 5 (Issue 8); DOI:10.1371/journal.pmed.0050169