Mussaret Bano Zaidi

• MD, MSc
• Georgetown University

Cytolethal distending toxins (CDTs), encoded by cdtABC genes, have DNase activity leading to cellular and nuclear distention, resulting in actin remodeling, irreversible cell cycle arrest and apoptosis of target cells. PCR cdt-positive Escherichia coli strains have been isolated from children with diarrhea worldwide. However, toxin production and b...

Objetivo. En respuesta a la creciente amenaza de riesgos pandémicos y la reciente experiencia de la pandemia de Covid-19, la UNAM a través del PUIREE convocó a un análisis multidisciplinario para identificar y priorizar acciones esenciales para la respuesta ante pandemias en México. Material y métodos. Se utilizó el método estructurado de comunicac...

Objective: Influenza is a costly disease for the population. It is a cause of seasonal morbidity and mortality, epidemics and pandemics or syndemics. Given the variability of the virus, surveillance systems are implemented in order to update the strains and include them in the annual influenza vaccine. This vaccine is currently recommended in some...

La influenza es una enfermedad costosa para la población. Es causa de morbimortalidad estacional, epidemias y pandemias o sindemias. Debido a la variabilidad del virus, se implementan sistemas de vigilancia para actualizar las cepas e incluirlas en la vacuna antiinfluenza anual. Actualmente se recomienda esta vacuna en algunos grupos de alto riesgo...

Background Recently, hoarseness affecting the supraglottic structure has been reported in Kawasaki Disease. The objective of this study was to characterize the frequency of hoarseness in acute KD patients in Latin America. Methods We used prospective data from the multinational REKAMLATINA Network (Red de Enfermedad de Kawasaki en America Latina)...

Diarrheagenic E. coli can be separated into six distinct pathotypes, with enteroaggregative (EAEC) and diffusely-adherent E. coli (DAEC) among the least characterized. To gain additional insights into these two pathotypes we performed whole genome sequencing of ten DAEC, nine EAEC strains, isolated from Mexican children with diarrhea, and one EAEC...

Diarrheagenic E. coli can be separated into six distinct pathotypes, with enteroaggregative (EAEC) and diffusely-adherent E. coli (DAEC) among the least characterized. To gain additional insights into these two pathotypes we performed whole genome sequencing of ten DAEC, nine EAEC strains, isolated from Mexican children with diarrhea, and one EAEC...

Purpose of review Vaccine hesitancy was identified as one of the top ten global health threats of 2019. Despite the spectacular reductions in morbidity and mortality achieved by vaccination programs, a growing anti-vaccine movement has led to the resurgence of previously controlled infectious diseases. This article discusses the causes and conseque...

Zika virus (ZIKV) is a mosquito-borne flavivirus that has caused recent large outbreaks in the Americas. Given its association with severe congenital defects including microcephaly, distinguishing infections caused by ZIKV from those caused by dengue virus (DENV) is of primordial importance. The objectives of this study were to evaluate the recombi...

Escherichia albertii is an emerging human enteropathogen. We report the draft genome sequence of E. albertii strain Mex-12/320a, isolated from an infant with diarrhea. The presence of the pathogenic island O122/IE6 and the nleA gene, previously found in diarrheagenic enteropathogenic Escherichia coli strains, suggests that E. albertii may cause acu...

The emergence of typhoid fever outbreaks in southeast Mexico and Central America are a regional public health threat. This paper describes a typhoid fever outbreak in Yucatan, Mexico, with a high rate of severe complications and therapeutic failures after the near-elimination of the disease for almost 40 years.

[This corrects the article DOI: 10.1099/jmmcr.0.005145.].

Background: Co-circulation of dengue virus (DENV) and chikungunya virus (CHIKV) is increasing worldwide but information on the viral dynamics and immune response to DENV-CHIKV co-infection, particularly in young infants, is scant. Methods: Blood samples were collected from 24 patients, aged 2 months to 82 years, during a CHIKV outbreak in Mexico...

BCG scar acute skin changes can be helpful in the clinical suspicion and diagnosis of Kawasaki Disease (KD) in countries where BCG vaccine is administered. Most publications come from Asia, where BCG scar changes occur in 10-50% of patients. These changes can vary from erythema+-edema, crust formation, up to ulcers. We describe the firstprospective...

Introduction Although the current Zika virus (ZIKV) epidemic is a major public health concern, most reports have focused on congenital ZIKV syndrome, its most devastating manifestation. Severe ocular complications associated with ZIKV infections and possible pathogenetic factors are rarely described. Here, we describe three Venezuelan patients who...

Infectious acute diarrhea is a frequent cause of morbidity and mortality in many countries of the world. Shigella sp., Salmonella sp. and diarreogenic Escherichia coli are the most common bacterial agents. Objective: To evaluate in vitro activity of Rifaximin and other seven antimicrobials prescribed against intestinal pathogens bacteria, isolated...

Justificación: La EK se confunde con ciertas enfermedades frecuentes de la niñez, y los ATBs no forman parte del tratamiento. Su uso retrasa el diagnóstico y tratamiento temprano. Objetivo: Reportar el primer estudio prospectivo multicéntrico de EK en México evaluando el uso de ATBs previo al diagnóstico de EK. Tipo y Diseño: Estudio prospectivo d...

Globally, diarrheal diseases are a leading cause of death in children under five and disproportionately affect children in developing countries. Children who contract diarrheal diseases are rarely screened to identify the etiologic agent due to time and cost considerations associated with pathogen-specific screening and hence pathogen-directed ther...

Clinical information and complete blood count data. (XLSX)

Relationship between PC1 and days past disease onset. (A) Principal component analysis, colored by days past disease onset. (B) PC1 values according to days past disease onset. (TIF)

Monocyte proportions and complement expression. Median complement gene expression as a function of the proportion of monocytes. (TIF)

Differentially expressed gene lists. (XLSX)

Background Although paediatricians are more familiar with thrombocytosis and its importance in KD, early thrombocytopenia can occur and is considered a risk factor for coronary artery lesions (CALs) and acute myocardial infarction (AMI). We describe the epidemiology, clinical aspects, CALs, and outcome of the largest prospective multinational study...

BACKGROUND: Delayed diagnosis of KD (>10 days of fever) is associated with higher rates of coronary artery lesions (CALs), other complications, IVIG-resistance, and need of steroids and other drugs. We describe the only prospective multinational multicenter study from Latin America (LA) analyzing children with KD in whom the diagnosis was made >10...

The envelope (E) protein from DENV, contain three functional and structural domains (DI, DII and DIII). Some studies suggest that neutralizing antibodies during natural DENV infection are predominantly against DI and DII, in contrast, low proportion of the antibodies were against DIII. Thus it is necessary to establish the proportion of human antib...

Introduction. Cytolethal distending toxins (CDTs), encoded by cdt genes, have DNase activity leading to cellular and nuclear distension, resulting in irreversible cell cycle arrest and apoptosis of target cells. cdt-positive Escherichia coli strains have been isolated from children with diarrhoea. There is, however, scant information on the prevale...

ackground: KD diagnosis at extreme age groups is difficult. Worldwide, approximately 20% of KD cases occur in ch >5 years; however, publications focusing on this age group are scarce. We describe the epidemiology, clinical aspects and treatment of the first prospective LA multinational study of KD in this age group. Methods: Ongoing prospective stu...

Background and aims: KD is associated with delayed diagnosis, and increased rates of atypical presentations, complications and worse outcomes in infants <6 months. We describe the epidemiology, clinical aspects and treatment of the first prospective LA multinational study of KD in infants <6 months of age. Methods: Ongoing prospective study of pati...

Background and aims: Mexico is one of Latin American (LA) countries in which there has been more research about KD epidemiology; however, most publications have been case reports and retrospective studies. We describe the epidemiology, clinical aspects and treatment of the largest prospective multicenter study of KD in Mexican children (ch) as part...

Background and aims: Prior to 2013, the regional epidemiology of KD in LA children was unknown and only individual reports from some countries were available. Our main objective is to describe the main success and challenges of prospective surveillance of KD by REKAMLATINA, the largest non-funded multinational network studying the epidemiology, cli...

Globally, diarrheal diseases are a leading cause of death in children under five and disproportionately affect children in developing countries. To identify changes in gene expression associated with diarrheal disease, we performed RNA sequencing on whole blood of 192 children less than 10 years of age with acute diarrhea at the Hospital General O’...

The complete genome of Salmonella enterica serovar Typhimurium strain SO3 (sequence type 302), isolated from a fatal meningitis infection in Mexico, was determined using PacBio technology. The chromosome hosts six complete prophages and is predicted to harbor 51 genomic islands, including 13 pathogenicity islands (SPIs). It carries the Salmonella v...

The complete genome sequence of Salmonella enterica serovar Typhimurium strain SO2, isolated from an asymptomatic child in Mexico, was determined using PacBio single-molecule real-time technology. Strain SO2 has six complete chromosomal prophages, namely, ST104, Gifsy-2, ST64B, Gifsy-1, ELPhiS, and FSL SP-004, and carries a Salmonella virulence pla...

The complete genome of Salmonella enterica subsp. enterica serovar Typhimurium sequence type 19 (ST19) strain YU15, isolated in Yucatán, Mexico, from a human baby stool culture, was determined using PacBio technology. The chromosome contains five intact prophages and the Salmonella genomic island 1 (SGI1). This strain carries the Salmonella virulen...

Unlabelled: Salmonella enterica serovar Typhimurium is one of the most common S. enterica serovars associated with U.S. foodborne outbreaks. S. Typhimurium bacteria isolated from humans exhibit wide-ranging virulence phenotypes in inbred mice, leading to speculation that some strains are more virulent in nature. However, it is unclear whether incr...

Single-copy core genes used in phylogenetic reconstruction. The locus tags in S. Typhimurium strain LT2, gene name, gene description, and coding strand for the 2,968 core genes included in sequence alignments for phylogenetic reconstruction are given. Download

Growth rate of S. Typhimurium strains 14028S and D23580 in tetrathionate-containing medium under anaerobic conditions. Strains 14028S (TtrC R187H) and D23580 (TtrC R187H, TtrS V421G, TtrA F301L) show similar growth rates when grown anaerobically in BBL tetrathionate broth. The number of CFU were determined at 0 and 24 h. The values are the means an...

The 14028S katE null mutant is deficient in catalase activity similar to the subclade 1a strains BC_2558 and SOHS02-20. Stationary-phase cultures of four strains were mixed with equal volumes of Triton X-100 and 30% hydrogen peroxide to assay global catalase activity. The formation of oxygen bubbles is apparent in wild-type strain 14028S; however,...

The set of genes uniquely interrupted (pseudogenes) or missing, and genes uniquely present, in each of the basal clades and subclades. The locus tag and gene name and description for 23 uniquely present and 35 uniquely interrupted or missing genes are given. The locus tags for genes unique to strains sequenced in this study are from PGAT (http://to...

ClonalFrameML analysis of recombination in the core gene data set. White vertical bars indicate reconstructed substitutions, and dark blue dots indicate putative recombination events for each branch of the ClonalFrameML tree. Position refers to the position in the final alignment of 2,968 core genes totaling 2,687,981 nucleotide positions. Clades a...

Details of Salmonella complete genomes or draft assemblies included in the present study. The genome size and number of contigs, coding genes, and pseudogenes for 56 S. Typhimurium strains and 1 S. Saintpaul strain are given. Download

The 573 nonsynonymous SNPs and 422 synonymous SNPs significantly associated with a basal clade or subclade. Annotation for each SNP, in addition to clade association and SIFT prediction, is shown. Download

Maximum likelihood phylogeny of 114 S. Typhimurium strains based on k-mers. Animal strains are colored blue. Collection location and year in bold type follow strain names and are abbreviated as follows: DC, Democratic Republic of the Congo; JP, Japan; MW, Malawi; MX, Mexico; MZ, Mozambique; UK, United Kingdom; US, United States. Strains with unknow...

Details of the Salmonella strains investigated

Background: Chronic granulomatous disease (CGD) is a rare primary immunodeficiency caused by inborn errors of the phagocyte nicotinamide adenine dinucleotide phosphate oxidase complex. From the first year of life onward, most affected patients display multiple, severe, and recurrent infections caused by bacteria and fungi. Mycobacterial infections...

Salmonella enterica subsp. enterica serovar Typhimurium strain YU39 was isolated in 2005 in the state of Yucatán, Mexico, from a human systemic infection. The YU39 strain is representative of the multidrug-resistant emergent sequence type 213 (ST213) genotype. The YU39 complete genome is composed of a chromosome and seven plasmids.

Diarrheagenic Escherichia coli (DEC) cause acute and persistent diarrhoea worldwide, but little is known about their epidemiology in Mexico. We determined the prevalence of bacterial entero-pathogens in 831 children with acute diarrhoea over a four-year period in Yucatan, Mexico. Six DEC supplementary virulence genes (SVG), mainly associated with e...

Antimicrobial resistance exacts worldwide an increasingly significant clinical and economic toll. Despite the international calls for urgent action, antimicrobial use and resistance have been low on the Mexican government's policy agenda. In early 2010, a multidisciplinary group of experts launched a national initiative for containment of antimicro...

Enteroaggregative Escherichia coli (EAEC) is a heterogeneous emerging enteric pathogen identified during the 1980s when EAEC strains were isolated from cases of acute and persistent diarrhea among infants in developing countries as well as traveler’s diarrhea. Subsequently, EAEC strains were linked with foodborne outbreaks and diarrhea illness in a...

Abstract Despite a significant decrease in Shigella-related mortality, shigellosis continues to carry a significant burden of disease worldwide, particularly in Asia and Africa. Shigella is a highly virulent pathogen comprised of four major species with numerous subtypes. Shigella dysenteriae and Shigella flexneri infections are predominant in reso...

Our observation that in the Mexican Salmonella Typhimurium population none of the ST19 and ST213 strains harbored both the Salmonella virulence plasmid (pSTV) and the prevalent IncA/C plasmid (pA/C) led us to hypothesize that restriction to horizontal transfer of these plasmids existed. We designed a conjugation scheme using ST213 strain YU39 as do...

Background: Salmonella and Shigella cause significant morbidity and mortality among children worldwide. Increased antimicrobial resistance results in greater burden of disease. Materials and Methods: From 2005 to 2011, Salmonella and Shigella isolates collected from ill children at a major hospital in Yucatan, Mexico, were subjected to serotyping a...

Diffusely adherent Escherichia coli (DAEC) is considered a causative organism of diarrhoea in children, but conclusive studies are lacking, as is also the case for other diarrheagenic E. coli (DEC). DEC pathotypes are differentiated on the basis of their pathogenic features, and thus cannot be quickly identified on selective culture media. Molecula...

Abstract We describe prevalence and antimicrobial susceptibility results for thermophilic Campylobacter isolates collected from humans, food, and food-animals in an integrated food chain surveillance network in Mexico. From 2003 to 2006, stool samples were collected from children with diarrhea at state sentinel hospitals. Concurrently, fecal sample...

The foodborne transmission and human health impact of Salmonella and Campylobacter infections have rarely been evaluated at the population level in highly endemic settings. A prospective 15-month cohort study of 127 infants and 119 elderly people was combined with animal and food surveillance to determine the incidence and severity of Salmonella an...

Table S2. Isolates sequenced and GenBank accession numbers.

Figure S1 – Clonal complex for the four multilocus genotypes found in the Mexican Typhimurium population. Representation of the clonal relatedness of STs. Figure S1 – Clonal complex for the four multilocus genotypes found in the Mexican Typhimurium population. The eBURST diagram show the genetic relationships for 66 Typhimurium strains based on the...

Salmonella Typhimurium ST213 was first detected in the Mexican Typhimurium population in 2001. It is associated with a multi-drug resistance phenotype and a plasmid-borne blaCMY-2 gene conferring resistance to extended-spectrum cephalosporins. The objective of the current study was to examine the association between the ST213 genotype and blaCMY-2...

Methods: Using a semi-structured questionnaire, we conducted a case-control study of risk factors for primary MDR-TB in San Juan de Lurigancho (SJL), a Lima district with the highest TB rates in Peru. Consecutive, consenting TB cases (drug sensitive (DS) and primary MDR-TB cases) followed in SJL clinics and randomly selected healthy community contr...

Geographic differences in frequency and azole resistance among Candida glabrata may impact empiric antifungal therapy choice. We examined geographic variation in isolation and azole susceptibility of C. glabrata. We examined 23 305 clinical isolates of C. glabrata during ARTEMIS DISK global surveillance. Susceptibility testing to fluconazole and vo...

Bacterial genomes are mosaic structures composed of genes present in every strain of the same species (core genome), and genes present in some but not all strains of a species (accessory genome). The aim of this study was to compare the genetic diversity of core and accessory genes of a Salmonella enterica subspecies enterica serovar Typhimurium (T...

Table S2 – Primers used in this study. The primer sequences, amplification sizes, annealing temperatures and references are listed. Table S2 – Primers used in this study. The primer sequences, amplification sizes, annealing temperatures and references are listed.

Fluconazole in vitro susceptibility test results determined by the CLSI M44-A disk diffusion method for 11,240 isolates of noncandidal yeasts were collected from 134 study sites in 40 countries from June 1997 through December 2007. Data were collected for 8,717 yeast isolates tested with voriconazole from 2001 through 2007. A total of 22 different...

Few developing countries have foodborne pathogen surveillance systems, and none of these integrates data from humans, food, and animals. We describe the implementation of a 4-state, integrated food chain surveillance system (IFCS) for Salmonella spp. in Mexico. Significant findings were 1) high rates of meat contamination (21.3%-36.4%), 2) high rat...

We describe the emergence and dissemination of multidrug-resistant (MDR) Salmonella Typhimurium in humans, retail meat and food animals from Yucatan, Mexico. Salmonella Typhimurium isolates were collected through an active surveillance system and tested for susceptibility to 12 antimicrobial agents. Isolates that were non-susceptible to ceftriaxone...

This review presents the studies on Salmonella conducted by three research groups in Mexico. Each of these groups belongs to different but complementary disciplines. The need for continuous epidemiological surveillance of Salmonella throughout the food chain, in conjunction with molecular typing of the isolates is discussed. The epidemiological and...

We report the results of a 3-year Salmonella surveillance study of persons with diarrhea; asymptomatic children; and retail pork, poultry, and beef in Yucatan, Mexico. Isolates were characterized according to serotype, antimicrobial susceptibility, and genetic relatedness with pulsed-field gel electrophoresis. Salmonella Typhimurium was the most co...

RESUMEN. En esta revisión se presenta el trabajo en Salmonella de tres grupos de investigación en México, cada uno en diferentes disci-plinas que son, sin embargo, complementarias. Se plantea, por un lado, la necesidad de una vigilancia epidemiológica continua de Sal-monella a lo largo de la cadena alimenticia, aunada a una tipificación molecular d...

We determined the prevalence of, and risk factors for, fecal quinolone-resistant Escherichia coli (QREC) in 324 children from Yucatan, Mexico. QREC was higher in children with recent Salmonella infection (100%) than in children with diarrhea (61%) or healthy children (54%) (P = 0.007). Multivariate analysis identified recent hospitalization of a fa...

Objetivo. Determinar la prevalencia de urolitiasis en el estado de Yucatán, México, y una posible asociación de ésta con antecedentes familiares de la enfermedad y la dureza del agua. Material y métodos. Durante 1996 se efectuó una encuesta transversal en población abierta mayor de un año de edad, del estado de Yucatán. Los sujetos se clasificaron...

To measure the prevalence of urolithiasis in Yucatan, and to establish a possible association of the disease with family history and water hardness. During 1996, a survey was conducted on the population over one year of age in the State of Yucatan. Subjects were classified as having definite lithiasis (DL), probable lithiasis (PL), or no lithiasis...

The impact of nosocomial infections and multidrug resistance on mortality is a topic of considerable controversy. A prospective, nested case control study was conducted in four intensive care units (ICUs) in Mexico to measure the impact of antibiotic resistance on and identify the main risk factors for mortality in critically ill patients with noso...

The in-vitro activity of fluconazole against 46,831 yeast isolates collected over a two-year period from 57 laboratories in 33 countries worldwide was assessed using a disc diffusion method. Candida albicans was the organism isolated most frequently, accounting for 68.6% of the total number of isolates. C. glabrata, C. tropicalis, C parapsilosis an...

Objective. To determine the main epidemiological, clinical, and microbiologic characteristics of an outbreak of ventilator-associated pneumonia at an intensive care unit in Yucatan. Material and methods. An 11 - month prospective and observational study was designed to determine incidence, mortality, potential reservoirs, etiologic agents and antib...

OBJETIVO. Determinar las principales características epidemiológicas, clínicas y microbiológicas de una epidemia de neumonía asociada a ventilación mecánica en una unidad de cuidados intensivos en Mérida, Yucatán. MATERIAL Y MÉTODOS. Se diseñó un estudio prospectivo y observacional de 11 meses para determinar incidencia, mortalidad, reservorios pot...

To determine the main epidemiological, clinical, and microbiologic characteristics of an outbreak of ventilator-associated pneumonia at an intensive care unit in Yucatan. An 11-month prospective and observational study was designed to determine incidence, mortality, potential reservoirs, etiologic agents and antibiotic susceptibility patterns. The...

We evaluated antisepsis, disinfection, and sterilization procedures at 22 hospitals in the state of Yucatan, Mexico, which provide services for approximately 80% of the population. The percentage of hospitals that followed standard recommendations for diverse antisepsis procedures were as follows: surgical scrub, 41%; surgical site preparation, 68%...

A one-year prospective study was conducted in a Pediatric Emergency Room at a hospital en Merida, Yucatan, Mexico, in order to evaluate the treatment of acute diarrhea and compare it to treatment previously administered by community doctors. Overall, 92% of the patients treated by community doctors were inappropriately treated compared to 32% of th...

Forty-six patients with neonatal tetanus (NT) were studied to identify factors for poor prognosis which could be used to select a therapeutic regimen with intravenous diazepam or neuromuscular blockade (NB) with pancuronium. Nine patients with NT grades II and III were successfully treated with diazepam; none of them died. Of the patients with NT g...

During a 10-month period a surveillance program was conducted to detect nosocomial infections (NIs) in the Pediatric Unit at the Hospital General O'Horan in Mérida, Yucatán. Five hundred and five infections were detected among 359 patients from a total of 2823 discharges, yielding a 17.9% rate. The NI rate among newborns delivered in the hospital w...

To know the incidence, etiology, risk factors, morbidity, and mortality of nosocomial diarrhea in adults. Nested case-control study, matched by service, length of stay, date of admission, and presence of leukopenia and/or the acquired immunodeficiency syndrome (AIDS). Cases were those who developed nosocomial diarrhea. Controls were those who did n...

Objective: To know the incidence, etiology, risk factors, morbidity, and mortality of nosocomial diarrhea in adults. Design: Nested case-control study, matched by service, length of stay, date of admission, and presence of leukopenia and/or the acquired immunodeficiency syndrome (AIDS). Cases were those who developed nosocomial diarrhea. Controls w...

An outbreak of hepatitis B virus infection in a hemodialysis unit which occurred after the arrival of an antigen carrier is described. During a period of five months, four cases were registered for an incidence of 14.8 percent, compared to 3.2 and 0 percent during preepidemic and postepidemic periods, respectively. There is no national surveillance...

A case-control study was conducted on an epidemic of bacteremia and meningitis caused by Serratia marcescens in the neonatal intensive care unit and special care nursery of a general hospital in Mexico City, Mexico. A 19.9% incidence of bacteremia and meningitis was recorded in contrast to 1.4% and 3.7% during preepidemic and post-epidemic periods;...