Lessons learned from detecting and responding to recurrent measles outbreak in Liberia post Ebola-Epidemic 2016-2017

Introduction: measles is an acute viral disease that remains endemic in much of sub-Sahara Africa, including Liberia. The 2014 Ebola epidemic disrupted an already fragile health system contributing to low uptake of immunization services, population immunity remained low thus facilitating recurrent outbreaks of measles in Liberia. We describe lessons learnt from detecting and responding to recurrent outbreaks of measles two years post the 2014 Ebola epidemic in Liberia.Methods: we conducted a descriptive study using the findings from Integrated Diseases Surveillance and Response (IDSR) 15 counties, National Public Health Institute of Liberia (NPHIL), National Public Health Reference Laboratory (NPHRL) and District Health Information Software (DIHS2) data conducted from October to December, 2017. We perused the outbreaks line lists and other key documents submitted by the counties to the national level from January 2016 to December 2017.Results: from January 2016 to December 2017, 2,954 suspected cases of measles were reported through IDSR. Four hundred sixty-seven (467) were laboratory confirmed (IgM-positive), 776 epidemiologically linked, 574 clinically confirmed, and 1,137 discarded (IgM-negative). Nine deaths out of 1817 cases were reported, a case fatality rate of 0.5%; 49% were children below the age of 5 years. Twenty-two percent (405/1817) of the confirmed cases were vaccinated while the vaccination status of 55% (994/1817) was unknown.Conclusion: revitalization of IDSR contributed to increased detection and reporting of suspected cases of measles thus facilitating early identification and response to outbreaks. Priority needs to be given to increasing the uptake of routine immunization services, introducing a second dose of measles vaccine in the routine immunization program and conducting a high-quality supplementary measles immunization campaign for age group 1 to 10 years to provide protection for a huge cohort of susceptible

Progress towards elimination of measles in Kenya, 2003-2016

Introduction: measles is targeted for elimination in the World Health Organization African Region by the year 2020. In 2011, Kenya was off track in attaining the 2012 pre-elimination goal. We describe the epidemiology of measles in Kenya and assess progress made towards elimination.Methods: we reviewed national case-based measles surveillance and immunization data from January 2003 to December 2016. A case was confirmed if serum was positive for anti-measles IgM antibody, was epidemiologically linked to a laboratory-confirmed case or clinically compatible. Data on case-patient demographics, vaccination status, and clinical outcome and measles containing vaccine (MCV) coverage were analyzed. We calculated measles surveillance indicators and incidence, using population estimates for the respective years.Results: the coverage of first dose MCV (MCV1) increased from 65% to 86% from 2003-2012, then declined to 75% in 2016. Coverage of second dose MCV (MCV2) remained < 50% since introduction in 2013. During 2003-2016, there were 26,188 suspected measles cases were reported, with 9043(35%) confirmed cases, and 165 deaths (case fatality rate, 1.8%). The non-measles febrile rash illness rate was consistently > 2/100,000 population, and "80% of the sub-national level investigated a case in 11 of the 14 years. National incidence ranged from 4 to 62/million in 2003-2006 and decreased to 3/million in 2016. The age specific incidence ranged from 1 to 364/million population and was highest among children aged < 1 year.Conclusion: Kenya has made progress towards measles elimination. However, this progress remains at risk and the recent declines in MCV1 coverage and the low uptake in MCV2 could reverse these gains

Trends in Performance of the National Measles Case-Based Surveillance System; Ministry of Health and Child Welfare; Zimbabwe (1999 - 2008)

Introduction: Since adoption of the measles case-based surveillance system in Zimbabwe in 1998; data has been routinely collected at all levels of the health delivery system and sent to national level with little or no documented evidence of use to identify risky populations; monitor impact of interventions and measure progress towards achieving measles elimination. We analysed this data to determine trends in the national measles case-based surveillance system (NMCBSS). Methods: A retrospective record review of the NMCBSS dataset for period 1999 -2008 was conducted; assessing trends in proportions of investigated cases; timeliness and nature of specimens received at laboratory; timeliness of feedback of serology results; proportion of cases confirmed as measles and national annualized rates of investigation. Comparisons with WHO performance indicators were done. The secondary data analysis was done in Excel and Epi-Info statistical software. Results: Cumulatively 4994 suspected cases were reported and investigated between 1999 and 2008. Reported suspected and confirmed measles cases declined from 24; 5 and 5.9 respectively in 2000 to 3.9and 1.0 respectively in 2008. Proportion of cases with blood specimens collected and proportion reaching laboratory timely increased from 83 and 65 respectively in 1999; to 100 and 82 respectively in 2008. Proportion of specimens arriving at laboratory in good condition improved from 65 in 2004 to 94 in 2008 while timeliness of feedback of serology results improved from 4 in 2004 to 65in 2008. Sensitivity of the NMCBSS however has been weakening; declining from 9.04 cases investigated per 100 000 population per year in 2000 to 1.58 cases/100 000/year in 2008. Conclusion: The NMCBSS improved in quality; timeliness and feedback of laboratory results of specimens sent for investigation; but its sensitivity declined mainly due to reduced capacity to detect and confirm measles cases. We recommend training staff on active surveillance of cases and more support and supervisory visits to strengthen EPI surveillance

Description et analyse d'une epidemie de rougeole a Bobo-Dioulasso; octobre 1995-mai 1996

De decembre 1995 a mai 1996; une epidemie de rougeole est survenue dans la ville de Bobo-Dioulasso; Burkina Faso. Des investigations ont ete realisees dans le but de mieux comprendre les caracteristiques et les determinants de cette epidemie. Une enquete exhaustive a ete realisee dans les formations sanitaires urbaines pour documenter tous les cas de rougeole mentionnes sur les registres de consultations. Tous les centres de vaccination ont ete visites pour evaluer leur plateau technique et la qualite de leurs prestations. Enfin; une enquete cas-temoins appariee sur l'age et le domicile (386 paires cas-temoins) ainsi qu'un sondage de couverture vaccinale selon le protocole OMS classique de 30 grappes ont complete les investigations par echantillonnage dans la population generale. Entre le 1er octobre 1995 et mi-mai 1996; 3768 cas de rougeole ont ete diagnostiques; soit un taux d'incidence cumule de 9;7 pour mille (34;6 pour mille avant 1 an; 28;9 pour mille de 1 a 4 ans; 10;7 pour mille de 5 a 14 ans et 4;8 pour mille a partir de 15 ans). L'epidemie a demarre fin novembre; debut decembre 1995; par des petits foyers dans un secteur central et dans deux secteurs peripheriques. A partir de mi-janvier 1996; elle s'est brutalement propagee et amplifiee dans le reste de la ville; pour culminer en mars et s'eteindre en mai

Au sujet d'un paradoxe; ou comment repondre aux rumeurs parfois desagreables a propos des cas de rougeole survenant chez des sujets vaccines

En situation d'epidemie; il est frequent d'entendre que beaucoup de malades rougeoleux avaient pourtant ete vaccines; que le vaccin est inefficace; que les gens de la sante ne font pas du travail serieux. Ce genre de plainte; bien comprehensible lorsqu'elle est formulee par des parents confrontes a cette situation facheuse; est malheureusement amplifiee par des professionnels de la sante; devient rumeur; est reprise par les medias. Le directeur national du programme elargi de vaccination est convoque chez le ministre; le responsable regional chez le haut-commissaire ou le prefet; etc

Measles in a West African nomadic community

A serological survey was conducted among Tuareg nomads to determine their level of immunity to measles. More than half (57.9%) of the children under 10 years of age did not have detectable antibodies to measles, suggesting that transmission of the disease is low in this mobile population. Mothers' reports of their children's history of measles were accurate (positive predictive value 93.9% for under-5-year-olds). Nomads are a reservoir of susceptible individuals who require immunization strategies adapted to their particular life-styles. These can be implemented at relatively low cost

Flambee des cas de rougeole dans la Province du Haut-Ogooue en janvier 1990/septembre 1991

Une flambee epidemiologique de cas de rougeole a ete signalee dans la Province du Haut-Ogooue entre janvier 1990 et septembre 1991. En effet; pres de 1208 cas ont ete declares au secteur des Grandes Endemies de Franceville par les formations sanitaires de la province. Le niveau de vaccination devrait alors etre maintenu par le programme elargi de vaccination afin d'eviter de telles poussees epidemiques

Measles epidemic in Harare, Zimbabwe, despite high measles immunization coverage rates

Despite rapidly increasing measles immunization coverage in Harare city, measles remains endemic, and regular outbreaks occur. The most recent occurred in 1988, when the measles immunization coverage was 83%. We have carried out a retrospective study of the clinical and epidemiological features of this outbreak to assess whether the present immunization policy needs to be changed. Of 4357 cases of measles seen at primary health care centres and hospitals in Harare during the outbreak, 1399 (32%) were severe or involved complications that required hospital admission. The peak incidence occurred among under-2-year-olds, followed by that among 5-7-year-olds. Poor nutritional status was significantly more frequent among children who were hospitalized and among those who died. A total of 59% of all cases aged 9-59 months had documented evidence of measles immunization. The most frequent complications, which occurred most often among under-5-year-olds, were diarrhoea with dehydration, pneumonia, laryngotracheobronchitis, and convulsions, which together affected 56% of hospitalized cases. The hospital case fatality rate was low (1.43%). In Harare, measles transmission remains a problem, despite high measles immunization coverage rates; the failure rate for the standard Schwarz measles vaccine also appears to be high. There is a need to reduce the number of measles cases among under-9-month-olds and young children. Further studies into alternative measles vaccines and schedules are required

Lack of efficacy of the standard potency Edmonston-Zagreb live, attenuated measles vaccine in African infants

The efficacy of standard potency Edmonston-Zagreb (E-Z) measles vaccine was tested in a randomized trial of Black infants in a rural area of South Africa where a measles epidemic was occurring. The following immunization schedules were used: 48 infants aged 4-8.5 months who received 3.9 log 50 infectious units of E-Z vaccine (group A); 48 infants aged 4-8.5 months who received 3.28 log 50 infectious units of Schwarz vaccine (group B); and 28 infants aged greater than 9 months who received 3.28 log 50 infectious units of Schwarz vaccine and served as controls (group C). For infants aged less than 23 weeks who were given either the E-Z or Schwarz vaccine, the number of seropositives was low (28%), irrespective of the pre-vaccination level of measles antibody. There was a higher number of seropositives (68%) among those in the age range greater than 23 weeks to less than 36 weeks who received the E-Z vaccine rather than the Schwarz vaccine (36%). When administered to children aged greater than 36 weeks, the Schwarz vaccine produced a satisfactory, though suboptimal response rate (61%). There was no correlation between seropositivity and pre-vaccination measles antibody status. Use of the standard dose of E-Z vaccine may have been one of the factors for this poor response, and this supports the WHO recommendation that titres higher than the standard potency vaccine are needed if 6-month-old infants are to be successfully immunized against measles

A study on measles in Kasungu

Findings from a December 1989 study indicate that a 28 percent of measles cases were in children under 9 months. Edmonston-Zagreb [EZ] vaccine which is administered at 6 months may seemingly reduce the worrying morbidity rate children below 9 months when introduced in the country