Last data update: Dec 09, 2024. (Total: 48320 publications since 2009)
Records 1-17 (of 17 Records) |
Query Trace: Cavallaro E[original query] |
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Supporting National Immunization Technical Advisory Groups (NITAGs) in development of evidence-based vaccine recommendations and NITAG assessments - New tools and approaches
Hadler SC , Shefer AM , Cavallaro KF , Ebama M , Tencza C , Kennedy ED , Ndiaye S , Shah A , Torre L , Bresee JS . Vaccine 2024 Increasing opportunities for prevention of infectious diseases by new, effective vaccines and the expansion of global immunization programs across the life course highlight the importance and value of evidence-informed decision-making (EIDM) by National Immunization Technical Advisory Groups (NITAGs). The U.S. Centers for Disease Control and Prevention (CDC) and Task Force for Global Health (TFGH) have developed and made available new tools to support NITAGs in EIDM. These include a toolkit for conducting facilitated training of NITAGs, Secretariats, or work groups on the use of the Evidence to Recommendations (EtR) approach to advise Ministries of Health (MoH) on specific vaccine policies, and an eLearning module on the EtR approach for NITAG members, Secretariat and others. The CDC and TFGH have also supported final development and implementation of the NITAG Maturity Assessment Tool (NMAT) for assessing maturity of NITAG capabilities in seven functional domains. The EtR toolkit and eLearning have been widely promoted in collaboration with the World Health Organization (WHO) Headquarters and Regional Offices through workshops engaging over 30 countries to date, and the NMAT assessment tool used in most countries in 3 WHO regions (Americas, Eastern Mediterranean, African). Important lessons have been learned regarding planning and conducting trainings for multiple countries and additional ways to support countries in applying the EtR approach to complete vaccine recommendations. Priorities for future work include the need to evaluate the impact of EtR training and NMAT assessments, working with partners to expand and adapt these tools for wider use, synergizing with other approaches for NITAG strengthening, and developing the best approaches to empower NITAGs to use the EtR approach. |
Strengthening National Immunization Technical Advisory Groups in resource-limited settings: current and potential linkages with polio national certification committees
Greene SA , Anya BM , Asghar H , Chaudhri IA , Datta SD , Donadel ME , Kouadio KI , Shefer AM , Cavallaro KF . Health Res Policy Syst 2020 18 (1) 116 BACKGROUND: Countries are transitioning assets and functions from polio eradication to integrated immunization and surveillance activities. We assessed the extent of linkages between and perceptions of National Immunization Technical Advisory Groups (NITAGs) and National Certification Committees (NCCs) for polio eradication to understand how linkages can be leveraged to improve efficiencies of these expert bodies. METHODS: During May 2017 to May 2018, we administered a 15-question survey to a NITAG chair or member and an NCC counterpart in all countries of the WHO Regions for Africa (AFR) and for the Eastern Mediterranean (EMR) that had both a NITAG and an NCC. Data were analysed using frequency distributions. RESULTS: Of countries with both a NITAG and an NCC (n = 44), the response rate was 92% (22/24) in AFR and 75% (15/20) in EMR. Some respondents reported being very familiar with the functions of the other technical bodies, 36% (8/22) for NITAG members and 38% (14/37) for NCC members. Over 85% (51/59) of respondents felt it was somewhat useful or very useful to strengthen ties between bodies. Nearly all respondents (98%, 58/59) felt that NCC expertise could inform measles and rubella elimination programmes. CONCLUSIONS: We observed a broad consensus that human resource assets of NCCs may serve an important technical role to support national immunization policy-making. At this stage of the polio eradication initiative, countries should consider how to integrate the technical expertise of NCC members to reinforce NITAGs and maintain the polio essential functions, beginning in countries that have been polio-free for several years. |
Building immunization decision-making capacity within the World Health Organization European Region
Mosina L , Sankar Datta S , Shefer A , Cavallaro KF , Henaff L , Steffen CA , Jacques-Carroll L . Vaccine 2020 38 (33) 5109-5113 A National Immunization Technical Advisory Group (NITAG) is a multi-disciplinary body of national experts that provides evidence-based recommendations to policy-makers, assisting them in making sound immunization policy and programme decisions. The World Health Organization (WHO) Regional Office for Europe is working to strengthen the capacity of newly-established NITAGs and has targeted efforts on low- and middle-income countries. The Regional Office, in collaboration with WHO Headquarters and USA Centers for Disease Control and Prevention (CDC), developed a new training strategy and held training workshops to improve NITAGs' functioning and ability to make evidence-based recommendations. Feedback from countries that participated in trainings indicated that the updated training materials and interactive approach with follow-up technical support enabled them to align their NITAG charters and processes with WHO recommendations. To ensure continued progress, global and regional partners such as WHO and CDC should continue providing technical support to recently established NITAGs. |
Supporting national immunization technical advisory groups (NITAGs) in resource-constrained settings. New strategies and lessons learned from the Task Force for Global Health's Partnership for influenza vaccine introduction
Ba-Nguz A , Shah A , Bresee JS , Lafond KE , Cavallaro K , Shefer A , Donadel M , Seward JF . Vaccine 2019 37 (28) 3646-3653 National Immunization Technical Advisory Groups (NITAGs) are multidisciplinary national experts who provide independent, evidence-informed vaccine policy recommendations to national health authorities. An essential NITAG function is to ensure that these decisions are grounded in the best available evidence generated through a systematic, transparent process. However, in many low- and middle-income countries (LMICs), experience with this decision making method is limited. The Task Force for Global Health manages the Partnership for Influenza Vaccine Introduction (PIVI) program in collaboration with the Centers for Disease Control and Prevention, Ministries of Health, corporate partners and others. During 2017, PIVI worked with its country partners and the World Health Organization regional and local offices to assess NITAG strengthening needs and to provide technical assistance in 7 LMIC countries (Laos Peoples Democratic Republic, Mongolia, Vietnam, Armenia, Cote d'Ivoire; Moldova and the Republic of Georgia). Our workshops supported general NITAG capacity building and the evidence-based review process using vaccines of interest to the country. For NITAGs reviewing evidence on seasonal influenza, we developed an influenza resource package to support their review and provide country-relevant information in an easy to use format. Of the seven NITAGs trained, six have applied some of the concepts learnt: revision or development of formal transparent, systematic procedures for their operations; preparation of recommendations on seasonal influenza vaccination using quality-assessed data from systematic searches and local data; and have applied the principles learned for making other new vaccine recommendations. Our experience confirms that LMIC NITAGs are considerably under-resourced without adequate technical support or access to global peer-reviewed literature. Ongoing support from NITAG partners must be secured and creative approaches might be needed to help countries achieve the GVAP 2020 target and support development of sustainable vaccine policies and programs. |
Demonstration of the use of remote temperature monitoring devices in vaccine refrigerators in Haiti
Cavallaro KF , Francois J , Jacques R , Mentor D , Yalcouye I , Wilkins K , Mueller N , Turner R , Wallace A , Tohme RA . Public Health Rep 2017 133 (1) 33354917742119 After the 2010 earthquake, Haiti committed to introducing 4 new antigens into its routine immunization schedule, which required improving its cold chain (ie, temperature-controlled supply chain) and increasing vaccine storage capacity by installing new refrigerators. We tested the feasibility of using remote temperature monitoring devices (RTMDs) in Haiti in a sample of vaccine refrigerators fueled by solar panels, propane gas, or electricity. We analyzed data from 16 RTMDs monitoring 24 refrigerators in 15 sites from March through August 2014. Although 5 of the 16 RTMDs exhibited intermittent data gaps, we identified typical temperature patterns consistent with refrigerator door opening and closing, propane depletion, thermostat insufficiency, and overstocking. Actual start-up, annual maintenance, and annual electricity costs for using RTMDs were $686, $179, and $9 per refrigerator, respectively. In Haiti, RTMD use was feasible. RTMDs could be prioritized for use with existing refrigerators with high volumes of vaccines and new refrigerators to certify their functionality before use. Vaccine vial monitors could provide additional useful information about cumulative heat exposure and possible vaccine denaturation. |
Strengthening and sustainability of national immunization technical advisory groups (NITAGs) globally: Lessons and recommendations from the founding meeting of the global NITAG network
Adjagba A , MacDonald NE , Ortega-Pérez I , Duclos P , 2016 Global NITAG Network Meeting Participants , Cavallaro K , Sheffer A . Vaccine 2017 35 (23) 3007-3011 National Immunization Technical Advisory Groups (NITAGs) provide independent, evidence-informed advice to assist their governments in immunization policy formation. However, many NITAGs face challenges in fulfilling their roles. Hence the many requests for formation of a network linking NITAGs together so they can learn from each other. To address this request, the Health Policy and Institutional Development (HPID) Center (a WHO Collaborating Center at the Agence de Médecine Préventive - AMP), in collaboration with WHO, organized a meeting in Veyrier-du-Lac, France, on 11 and 12 May 2016, to establish a Global NITAG Network (GNN). The meeting focused on two areas: the requirements for (a) the establishment of a global NITAG collaborative network; and (b) the global assessment/evaluation of the performance of NITAGs. 35 participants from 26 countries reviewed the proposed GNN framework documents and NITAG performance evaluation. Participants recommended that a GNN should be established, agreed on its governance, function, scope and a proposed work plan as well as setting a framework for NITAG evaluation. |
Expansion of vaccination services and strengthening vaccine-preventable diseases surveillance in Haiti, 2010-2016
Tohme RA , Francois J , Cavallaro KF , Paluku G , Yalcouye I , Jackson E , Wright T , Adrien P , Katz MA , Hyde TB , Faye P , Kimanuka F , Dietz V , Vertefeuille J , Lowrance D , Dahl B , Patel R . Am J Trop Med Hyg 2017 97 28-36 Following the 2010 earthquake, Haiti was at heightened risk for vaccine-preventable diseases (VPDs) outbreaks due to the exacerbation of long-standing gaps in the vaccination program and subsequent risk of VPD importation from other countries. Therefore, partners supported the Haitian Ministry of Health and Population to improve vaccination services and VPD surveillance. During 2010-2016, three polio, measles, and rubella vaccination campaigns were implemented, achieving a coverage > 90% among children and maintaining Haiti free of those VPDs. Furthermore, Haiti is on course to eliminate maternal and neonatal tetanus, with 70% of communes achieving tetanus vaccine two-dose coverage > 80% among women of childbearing age. In addition, the vaccine cold chain storage capacity increased by 91% at the central level and 285% at the department level, enabling the introduction of three new vaccines (pentavalent, rotavirus, and pneumococcal conjugate vaccines) that could prevent an estimated 5,227 deaths annually. Haiti moved from the fourth worst performing country in the Americas in 2012 to the sixth best performing country in 2015 for adequate investigation of suspected measles/rubella cases. Sentinel surveillance sites for rotavirus diarrhea and meningococcal meningitis were established to estimate baseline rates of those diseases prior to vaccine introduction and to evaluate the impact of vaccination in the future. In conclusion, Haiti significantly improved vaccination services and VPD surveillance. However, high dependence on external funding and competing vaccination program priorities are potential threats to sustaining the improvements achieved thus far. Political commitment and favorable economic and legal environments are needed to maintain these gains. |
Strengthening laboratory capacity through the surveillance of rotavirus gastroenteritis in Central Africa: the Surveillance Epidemiologique en Afrique Centrale (SURVAC) Project
Waku-Kouomou D , Esona MD , Pukuta E , Gouandijka-Vasilache I , Boula A , Dahl BA , Mondonge V , Mekontso D , Guifara G , Mbary-Daba R , Lewis J , Yahaya AA , Mwenda JM , Cavallaro KF , Gody JC , Muyembe JJ , Ndombo PK , Bowen MD . Trop Med Int Health 2015 21 (1) 122-130 OBJECTIVES: The goal of the SURVAC pilot project was to strengthen disease surveillance and response in three countries; Cameroon (CAE), Democratic Republic of the Congo (DRC) and Central African Republic (CAR). METHODS: Seven laboratories involved in rotavirus surveillance were provided with equipment, reagents and supplies. CDC and WHO staff provided on-site classroom and bench training in biosafety, quality assurance, quality control (QC), rotavirus diagnosis using Enzyme Immunoassay (EIA), and genotyping of rotavirus strains using the Reverse-Transcription Polymerase chain reaction (RT-PCR). All laboratory data were reported through WHO/AFRO. RESULTS: 23 staff members were trained on RT-PCR for rotavirus genotyping which was introduced for the first time in all three countries. In CAE, the number of samples analyzed by EIA and RT-PCR increased tenfold between 2007 and 2013. In DRC, this number increased fivefold, from 2009 to 2013 whereas in CAR, it increased fourfold between 2011 and 2013. All laboratories passed WHO proficiency testing in 2014. CONCLUSION: Laboratory capacity was strengthened through equipping laboratories and strengthening a sub-regional laboratory workforce for surveillance of rotavirus gastroenteritis. Each of the three countries generated rotavirus surveillance and genotyping data enabling the mapping of circulating genotypes. These results will help monitor the impact of rotavirus vaccination in these countries. |
Expansion of syndromic vaccine preventable disease surveillance to include bacterial meningitis and Japanese encephalitis: evaluation of adapting polio and measles laboratory networks in Bangladesh, China and India, 2007-2008
Cavallaro KF , Sandhu HS , Hyde TB , Johnson BW , Fischer M , Mayer LW , Clark TA , Pallansch MA , Yin Z , Zuo S , Hadler SC , Diorditsa S , Hasan AS , Bose AS , Dietz V . Vaccine 2015 33 (9) 1168-75 BACKGROUND: Surveillance for acute flaccid paralysis with laboratory confirmation has been a key strategy in the global polio eradication initiative, and the laboratory platform established for polio testing has been expanded in many countries to include surveillance for cases of febrile rash illness to identify measles and rubella cases. Vaccine-preventable disease surveillance is essential to detect outbreaks, define disease burden, guide vaccination strategies and assess immunization impact. Vaccines now exist to prevent Japanese encephalitis (JE) and some etiologies of bacterial meningitis. METHODS: We evaluated the feasibility of expanding polio-measles surveillance and laboratory networks to detect bacterial meningitis and JE, using surveillance for acute meningitis-encephalitis syndrome in Bangladesh and China and acute encephalitis syndrome in India. We developed nine syndromic surveillance performance indicators based on international surveillance guidelines and calculated scores using supervisory visit reports, annual reports, and case-based surveillance data. RESULTS: Scores, variable by country and targeted disease, were highest for the presence of national guidelines, sustainability, training, availability of JE laboratory resources, and effectiveness of using polio-measles networks for JE surveillance. Scores for effectiveness of building on polio-measles networks for bacterial meningitis surveillance and specimen referral were the lowest, because of differences in specimens and techniques. CONCLUSIONS: Polio-measles surveillance and laboratory networks provided useful infrastructure for establishing syndromic surveillance and building capacity for JE diagnosis, but were less applicable for bacterial meningitis. Laboratory-supported surveillance for vaccine-preventable bacterial diseases will require substantial technical and financial support to enhance local diagnostic capacity. |
Molecular surveillance of rotavirus strains circulating in Yaoundé, Cameroon, September 2007-December 2012.
Boula A , Waku-Kouomou D , Kinkela MN , Esona MD , Kemajou G , Mekontso D , Seheri M , Ndze VN , Emah I , Ela S , Dahl BA , Kobela M , Cavallaro KF , Mballa GA , Genstch JR , Bowen MD , Ndombo PK . Infect Genet Evol 2014 28 470-5 Rotavirus is the most common cause of severe diarrheal disease in children under 5 years of age worldwide. The World Health Organization (WHO) estimated that 453,000 rotavirus-attributable deaths occur annually. Through the WHO, the Rotavirus Sentinel Surveillance Program was established in Cameroon in September 2007 with the Mother and Child Center (MCC) in Yaounde playing the role of sentinel site and national laboratory for this program. The objectives of this surveillance were to assess the rotavirus disease burden and collect baseline information on rotavirus strains circulating in Cameroon. Diarrheal stool samples were collected in a pediatric hospital from children under 5, using the WHO case definition for rotavirus diarrhea. Antigen detection of rotavirus was performed by using an enzyme immunoassay (EIA). The genotypic characterization was performed using multiplexed semi-nested reverse transcription-polymerase chain reaction (RT-PCR) assays. Between September 2007 and December 2012, 2444 stool samples were received at the MCC laboratory for rotavirus antigen detection, of which 999 (41%) were EIA positive. Among EIA positive samples 898 were genotyped. Genotype prevalence varied each year. Genotype G9P[8] was the dominant type during 2007 (32%) and 2008 (24%), genotype G3P[6] predominated in 2010 (36%) and 2011 (25%), and G1P[8] was predominant in 2012 (44%). The findings showed that the rotavirus disease burden is high and there is a broad range of rotavirus strains circulating in Yaounde. These data will help measure the impact of vaccination in the future. |
Molecular surveillance of rotavirus infection in Bangui, Central African Republic, October 2011-September 2013.
Banga-Mingo V , Waku-Kouomou D , Gody JC , Esona MD , Yetimbi JF , Mbary-Daba R , Dahl BA , Dimanche L , Koyazegbe TD , Tricou V , Cavallaro KF , Guifara G , Bowen MD , Gouandjika-Vasilache I . Infect Genet Evol 2014 28 476-9 BACKGROUND: The World Health Organization (WHO) recommends the introduction of rotavirus vaccine in the immunization program of all countries. In the Central African Republic (CAR), sentinel surveillance for rotavirus gastroenteritis was established in 2011 by the Ministry of Health, with the support of the Surveillance en Afrique Centrale Project (SURVAC). The purpose of this study was to assess the burden of rotavirus gastroenteritis and to identify rotavirus strains circulating in CAR before the introduction of rotavirus vaccine planned for this year, 2014. METHODS: One sentinel site and one laboratory at the national level were designated by the CAR Ministry of Health to participate in this surveillance system. Stool samples were collected from children who met the WHO rotavirus gastroenteritis case definition (WHO, 2006). The samples were first screened for group A rotavirus antigen by enzyme immunoassay (EIA), and genotyping assays performed using a multiplex reverse transcriptase PCR (RT-PCR) technique. RESULTS: Between October 2011 and September 2013, 438 stool samples were collected and analyzed for detection of rotavirus antigen; 206 (47%) were positive. Among the 160 (78%) that could be genotyped, G2P[6] was the predominant strain (47%) followed by G1P[8] (25%) and G2P[4] (13%). CONCLUSIONS: Almost half of stool samples obtained from children hospitalized with gastroenteritis were positive for rotavirus. These baseline rotavirus surveillance data will be useful to health authorities considering rotavirus vaccine introduction and for evaluating the efficacy of rotavirus vaccine once it is introduced into the routine immunization system. |
Measles and rubella vaccination coverage in Haiti, 2012: progress towards verifying and challenges to maintaining measles and rubella elimination
Tohme RA , Francois J , Wannemuehler K , Magloire R , Carolina Danovaro-Holliday M , Flannery B , Cavallaro KF , Fitter DL , Purcell N , Dismer A , Tappero JW , Vertefeuille JF , Hyde TB . Trop Med Int Health 2014 19 (9) 1105-15 OBJECTIVES: We conducted a nationwide survey to assess measles containing vaccine (MCV) coverage among children aged 1-9 years in Haiti and identify factors associated with vaccination before and during the 2012 nationwide supplementary immunisation activities (SIA). METHODS: Haiti was stratified into five geographic regions (Metropolitan Port-au-Prince, North, Centre, South and West), 40 clusters were randomly selected in each region, and 35 households were selected per cluster. RESULTS: Among the 7000 visited households, 75.8% had at least one child aged 1-9 years; of these, 5279 (99.5%) households consented to participate in the survey. Of 9883 children enrolled, 91% received MCV before and/or during the SIA; 31% received MR for the first time during the SIA, and 50.7% received two doses of MCV (one before and one during the 2012 SIA). Among the 1685 unvaccinated children during the SIA, the primary reason of non-vaccination was caregivers not being aware of the SIA (31.0%). Children aged 1-4 years had significantly lower MR SIA coverage than those aged 5-9 years (79.5% vs. 84.8%) (P < 0.0001). A higher proportion of children living in the West (12.3%) and Centre (11.2%) regions had never been vaccinated than in other regions (4.8-9.1%). Awareness, educational level of the mother and region were significantly associated with MR vaccination during and before the SIA (P < 0.001). CONCLUSIONS: The 2012 SIA successfully increased MR coverage; however, to maintain measles and rubella elimination, coverage needs to be further increased among children aged 1-4 years and in regions with lower coverage. |
Molecular surveillance of rotavirus infection in the Democratic Republic of the Congo August 2009 to June 2012.
Pukuta ES , Esona MD , Nkongolo A , Seheri M , Makasi M , Nyembwe M , Mondonge V , Dahl BA , Mphahlele MJ , Cavallaro K , Gentsch J , Bowen MD , Waku-Kouomou D , Muyembe JJ . Pediatr Infect Dis J 2014 33 (4) 355-9 BACKGROUND: Rotavirus is a major cause of severe diarrhea worldwide. It causes 453,000 deaths in children annually. In the Democratic Republic of the Congo, sentinel site surveillance of rotavirus gastroenteritis started in 2009 and aimed to document burden of rotavirus diarrhea and identify circulating rotavirus genotypes. METHODS: Between August 2009 to June 2012, stool samples were collected in Kinshasa and Lubumbashi, from children <5 years of age who met the WHO case definition for rotavirus gastroenteritis. Rotavirus antigen detection was performed using an enzyme immunoassay technique and rotavirus strains were characterized using a multiplex reverse transcription polymerase chain reaction assay. RESULTS: During the study period, 1614 stool samples were screened for rotavirus by enzyme immunoassay and 990 (61%) were positive. Of these, the genotype was determined in 330 (33%) samples. The most common genotypes found in the samples analyzed were G1P[8] in 2009 (28%) and 2012 (33%), G2P[4] (33%) in 2010 and G2P[6] (28%) in 2011. Uncommon strains like G8P[6] (5%), G6P[6] (5%), G12P[6] (3%), G12P[8] (3%) and G8P[8] (2%) were also detected. CONCLUSIONS: In Democratic Republic of the Congo, 61% of the diarrhea in children in <5 years of age was caused by rotavirus infection and a variety of rotavirus genotypes were detected. Implementation of rotavirus genotyping at the national level has improved the timely identification of rotavirus strains. These results will help decision makers in Democratic Republic of the Congo plan the implementation of a rotavirus vaccination program. |
Salmonella typhimurium infections associated with peanut products
Cavallaro E , Date K , Medus C , Meyer S , Miller B , Kim C , Nowicki S , Cosgrove S , Sweat D , Phan Q , Flint J , Daly ER , Adams J , Hyytia-Trees E , Gerner-Smidt P , Hoekstra RM , Schwensohn C , Langer A , Sodha SV , Rogers MC , Angulo FJ , Tauxe RV , Williams IT , Behravesh CB . N Engl J Med 2011 365 (7) 601-10 BACKGROUND: Contaminated food ingredients can affect multiple products, each distributed through various channels and consumed in multiple settings. Beginning in November 2008, we investigated a nationwide outbreak of salmonella infections. METHODS: A case was defined as laboratory-confirmed infection with the outbreak strain of Salmonella Typhimurium occurring between September 1, 2008, and April 20, 2009. We conducted two case-control studies, product "trace-back," and environmental investigations. RESULTS: Among 714 case patients identified in 46 states, 166 (23%) were hospitalized and 9 (1%) died. In study 1, illness was associated with eating any peanut butter (matched odds ratio, 2.5; 95% confidence interval [CI], 1.3 to 5.3), peanut butter-containing products (matched odds ratio, 2.2; 95% CI, 1.1 to 4.7), and frozen chicken products (matched odds ratio, 4.6; 95% CI, 1.7 to 14.7). Investigations of focal clusters and single cases associated with nine institutions identified a single institutional brand of peanut butter (here called brand X) distributed to all facilities. In study 2, illness was associated with eating peanut butter outside the home (matched odds ratio, 3.9; 95% CI, 1.6 to 10.0) and two brands of peanut butter crackers (brand A: matched odds ratio, 17.2; 95% CI, 6.9 to 51.5; brand B: matched odds ratio, 3.6; 95% CI, 1.3 to 9.8). Both cracker brands were made from brand X peanut paste. The outbreak strain was isolated from brand X peanut butter, brand A crackers, and 15 other products. A total of 3918 peanut butter-containing products were recalled between January 10 and April 29, 2009. CONCLUSIONS: Contaminated peanut butter and peanut products caused a nationwide salmonellosis outbreak. Ingredient-driven outbreaks are challenging to detect and may lead to widespread contamination of numerous food products. |
Evaluation of pot-chlorination of wells during a cholera outbreak, Bissau, Guinea-Bissau, 2008
Cavallaro EC , Harris JR , Goia MSda , Barrado JCdos S , Nóbrega AAda , Alvarenga Júnior ICde , Silva AP , Sobel J , Mintz E . J Water Health 2011 9 (2) 394-402 We evaluated the ability of UNICEF-designed pot-chlorinators to achieve recommended free residual chlorine (FRC) levels in well water in Bissau, Guinea-Bissau, during a cholera outbreak. Thirty wells were randomly selected from six neighbourhoods. Pot-chlorinators - perforated plastic bottles filled with gravel, sand and calcium hypochlorite granules - were placed in each well. FRC was measured before and 24, 48 and 72 h after placement and compared with World Health Organization (WHO)-recommended levels of ≥1 mg L-1 for well water during cholera outbreaks and 0.2-5 mg L-1 in non-outbreak settings. Presence of well covers, distance from wells to latrines, and rainfall were noted. Complete post-chlorination data were collected from 26 wells. At baseline, no wells had FRC >0.09 mg L-1. At 24, 48 and 72 h post-chlorination, 4 (15%), 1 (4%) and 0 wells had FRC ≥1 mg L-1 and 16 (62%), 4 (15%) and 1 (4%) wells had FRC between 0.2 and 5 mg L-1, respectively. Several families reported discontinuing household water chlorination after wells were treated with pot-chlorinators. Pot-chlorinators failed to achieve WHO-recommended FRC levels in well water during a cholera outbreak, and conveyed a false sense of security to local residents. Pot-chlorination should be discouraged and alternative approaches to well-water disinfection promoted. |
Evaluation of three commercially available Japanese encephalitis virus IgM enzyme-linked immunosorbent assays
Robinson JS , Featherstone D , Vasanthapuram R , Biggerstaff BJ , Desai A , Ramamurty N , Chowdhury AH , Sandhu HS , Cavallaro KF , Johnson BW . Am J Trop Med Hyg 2010 83 (5) 1146-1155 We evaluated performance of three commercial Japanese encephalitis virus (JEV) IgM antibody capture enzyme-linked immunosorbent assay (MAC ELISA) kits with a panel of serological specimens collected during a surveillance project of acute encephalitis syndrome in India and acute meningitis and encephalitis syndrome in Bangladesh. The serum and cerebral spinal fluid specimens had been referred to the Centers for Disease Control and Prevention (CDC) for confirmatory testing. The CDC results and specimen classifications were considered the reference standard. All three commercial kits had high specificity (95-99.5%), but low sensitivities, ranging from 17-57%, with both serum and cerebrospinal fluid samples. Specific factors contributing to low sensitivity compared with the CDC ELISA could not be determined through further analysis of the limits and dilution end points of IgM detection. |
Field evaluation of crystal VC Rapid Dipstick test for cholera during a cholera outbreak in Guinea-Bissau
Harris JR , Cavallaro EC , de Nobrega AA , Dos SBarrado JC , Bopp C , Parsons MB , Djalo D , Fonseca FG , Ba U , Semedo A , Sobel J , Mintz ED . Trop Med Int Health 2009 14 (9) 1117-21 OBJECTIVES: To evaluate performance characteristics and ease of use of the new commercially available Crystal VC Rapid Dipstick (VC) test (Span Diagnostics, India) for Vibrio cholerae O1 and O139. METHODS: Whole stool was collected from patients presenting to a hospital cholera ward during a 2008 epidemic in Guinea-Bissau. The VC test on stool samples was conducted on-site; samples were subsequently stored in Cary-Blair transport media and sent to the Centers for Disease Control and Prevention for diagnostic testing by culture and polymerase chain reaction (PCR). In addition, four local laboratory technicians who were unfamiliar with the test were provided with stool samples, the VC test kit, and simple written instructions and asked to perform the test and interpret results. RESULTS: A total of 101 stool specimens were collected and tested. Compared with PCR, the test was 97% sensitive and 71-76% specific. Laboratory technicians in Bissau performed the test and interpreted results correctly using only simple written instructions. CONCLUSIONS: The VC test may be useful for cholera diagnosis in outbreak situations where laboratory capacity is limited. |
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