An Upsurge of Measles Cases in Mali-a Consequence of Pandemic-associated Disruption in Routine Immunization.

Measles deaths highlight immunization program gaps. In the Child Health and Mortality Prevention Surveillance study in Mali, we observed a rise in under-5 measles-related deaths in 2022 that corresponded with increased measles cases at the same time and a decline in measles vaccine coverage in Mali in 2020.

The Etiology of Childhood Pneumonia in Mali: Findings From the Pneumonia Etiology Research for Child Health (PERCH) Study.

BACKGROUND: We present findings from the Pneumonia Etiology Research for Child Health (PERCH) site in Bamako, Mali. METHODS: Cases were patients 28 days to 59 months of age, admitted to hospital with severe or very severe pneumonia (2005 World Health Organization definition). Community controls were frequency matched by age. Both provided nasopharyngeal and oropharyngeal swabs for multiplex polymerase chain reaction and Streptococcus pneumoniae culture. Cases underwent blood culture and induced sputum culture for Mycobacterium tuberculosis. A subset had pleural fluid and lung aspirates collected for culture and polymerase chain reaction. Primary analyses included participants with negative or unknown HIV status (HIV-) and cases with abnormal chest radiographs (CXR+). Cases and controls were compared using logistic regression adjusting for age. Etiologic fractions were calculated by a Bayesian nested partially latent class analysis, the PERCH integrated analysis. RESULTS: Between January 1, 2012, and January 14, 2014, we enrolled 241 CXR+/HIV- cases and 725 HIV- controls. Compared with controls, cases were more likely to have moderate-to-severe wasting (43.1% vs. 14.1%, P < 0.001) and stunting (26.6% vs. 9.4%, P < 0.001). Predominant etiologies were respiratory syncytial virus [24.0%; 95% credible interval (CrI): 18.3%-31.1%], S. pneumoniae (15.2%; 95% CrI: 9.5-21.6), human metapneumovirus (11.8%; 95% CrI: 8.3%-16.2%) and parainfluenza virus type 3 (9.0%; 95% CrI: 5.8%-13.3%). Case fatality was 13.3%, with Staphylococcus aureus, Pneumocystis jirovecii and Haemophilus influenzae type b predominating (40% of fatal cases). CONCLUSIONS: PERCH uncovered high case fatality among children with severe pneumonia in Mali, highlighting a role for new interventions (eg, respiratory syncytial virus vaccines) and a need to improve vaccine coverage and strengthen healthcare delivery.

Standardization of Clinical Assessment and Sample Collection Across All PERCH Study Sites.

BACKGROUND.: Variable adherence to standardized case definitions, clinical procedures, specimen collection techniques, and laboratory methods has complicated the interpretation of previous multicenter pneumonia etiology studies. To circumvent these problems, a program of clinical standardization was embedded in the Pneumonia Etiology Research for Child Health (PERCH) study. METHODS.: Between March 2011 and August 2013, standardized training on the PERCH case definition, clinical procedures, and collection of laboratory specimens was delivered to 331 clinical staff at 9 study sites in 7 countries (The Gambia, Kenya, Mali, South Africa, Zambia, Thailand, and Bangladesh), through 32 on-site courses and a training website. Staff competency was assessed throughout 24 months of enrollment with multiple-choice question (MCQ) examinations, a video quiz, and checklist evaluations of practical skills. RESULTS.: MCQ evaluation was confined to 158 clinical staff members who enrolled PERCH cases and controls, with scores obtained for >86% of eligible staff at each time-point. Median scores after baseline training were ≥80%, and improved by 10 percentage points with refresher training, with no significant intersite differences. Percentage agreement with the clinical trainer on the presence or absence of clinical signs on video clips was high (≥89%), with interobserver concordance being substantial to high (AC1 statistic, 0.62-0.82) for 5 of 6 signs assessed. Staff attained median scores of >90% in checklist evaluations of practical skills. CONCLUSIONS.: Satisfactory clinical standardization was achieved within and across all PERCH sites, providing reassurance that any etiological or clinical differences observed across the study sites are true differences, and not attributable to differences in application of the clinical case definition, interpretation of clinical signs, or in techniques used for clinical measurements or specimen collection.

Invasive Nontyphoidal Salmonella Infections Among Children in Mali, 2002-2014: Microbiological and Epidemiologic Features Guide Vaccine Development.

BACKGROUND: In 2002, following establishment of a clinical microbiology laboratory in the government hospital that admits children with severe illnesses in Bamako, Mali, surveillance to identify pathogens causing invasive bacterial infections (septicemia, bacteremia, meningitis, etc) was initiated. METHODS: Parents/guardians of children aged <16 years admitted to l'Hôpital Gabriel Touré with high fever or clinical syndromes compatible with focal invasive bacterial disease were asked for consent to culture their child's blood/body fluid. Standard bacteriologic techniques speciated isolates; Salmonella serovars were determined. RESULTS: From July 2002 through June 2014, 687 nontyphoidal Salmonella (NTS) isolates were obtained from 667 children; 667 yielded a single serovar and 20 grew 2 Salmonella serovars, 1 being NTS. Four serovars accounted for 87% of the 687 NTS isolates, including Salmonella Enteritidis (n = 244 [35.5%]), Salmonella Typhimurium (n = 221 [32.2%]), I:4,[5],12:i:- (n = 42 [6.1%]), and Salmonella Dublin (n = 89 [13.0%]). Of 553 patients with invasive NTS from whom 1 of the 4 predominant serovars was isolated in pure culture, 448 (81.0%) were aged <5 years and case fatality was 20.3%; Salmonella Enteritidis case fatality (27.8%) was higher than for other serovars (P = .0009). NTS disease showed a seasonal peak following the rainy season and into the cool, dry season. Since 2010, Salmonella Enteritidis cases have risen and Salmonella Typhimurium fallen. CONCLUSIONS: NTS has become the predominant invasive pathogen as Haemophilus influenzae type b and pneumococcal vaccine use in Mali has diminished invasive disease due to those pathogens. The age distribution and limited serovars involved make control of NTS disease by vaccines epidemiologically feasible, if products under development prove safe and efficacious.