Roma Chilengi

Centre for Infectious Disease Research in Zambia | CIDRZ · Health Systems and Primary Health Care

Cholera remains a significant public health burden in many countries in sub-Saharan Africa, though the exact mechanisms of bacterial emergence and spread remain largely undefined. We generated genomic data from 728 Vibrio cholerae O1 isolates predominantly collected between 2019-2024 to create the largest dataset of V. cholerae genomes sequenced lo...

Accurate cause-of-death statistics are vital for public health policy, but less than one-third of deaths globally are assigned a cause. Verbal autopsy (VA) methods are crucial in low- and middle-income countries lacking complete civil registration and vital statistics (CRVS) systems. We explored VA implementation in Zambia by using a previously dev...

Background Antimicrobial stewardship programmes (ASPs) aim to optimize antibiotic use and prevent antimicrobial resistance. Objective This study assessed the impact of ASPs, initiated using a hub-and-spoke approach, on antibiotic use in Zambian public hospitals. Methods A pre–post study was conducted in 10 ASP-naive hospitals across Zambia using...

Background The inappropriate use of antibiotics in hospitals contributes to the development and spread of antimicrobial resistance (AMR). This study evaluated the prevalence of antibiotic use and adherence to the World Health Organization (WHO) Access, Watch and Reserve (AWaRe) classification of antibiotics across 16 hospitals in Zambia. Methods A...

Background Antimicrobial stewardship (AMS) programs are critical in combating antimicrobial resistance (AMR). In Zambia, there is little information regarding the capacity of hospitals to establish and implement AMS programs. The objective of this study was to conduct a baseline assessment of WHO core elements for an AMS program implementation in e...

Background The number of COVID-19 deaths reported in Zambia (N = 4069) is most likely an underestimate due to limited testing, incomplete death registration and inability to account for indirect deaths due to socioeconomic disruption during the pandemic. We sought to assess excess mortality during the COVID-19 pandemic in Zambia. Methods We conduc...

Background: The World Health Organization declared a global cholera emergency in 2023 due to an increase in cholera outbreaks, with most cholera-associated deaths reported in Africa. Characterizing large-scale burden patterns can help with monitoring progress in cholera control and targeting interventions. Methods: We modeled the mean annual incide...

Antimicrobial resistance (AMR) is a public health problem exacerbated by the overuse and misuse of antibiotics and the inadequate capacity of laboratories to conduct AMR surveillance. This study assessed the capacity of laboratories in seven faith-based hospitals to conduct AMR testing and surveillance in Zambia. This multi-facility, cross-sectiona...

Wastewater-based surveillance has emerged as an important method for monitoring the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). This study investigated the presence of SARS-CoV-2 in wastewater in Zambia. We conducted a longitudinal study in the Copperbelt and Eastern provinces of Zambia from October 2023 to December 2023 during wh...

Background Cholera outbreaks are increasing in frequency and severity, particularly in Sub-Saharan Africa. Zambia, committed to ending cholera by 2025, is coming off its most significant outbreak in 2024. This review examines the perceived regression in elimination efforts by addressing two questions: (1) what is known about cholera in Zambia; and...

There are growing concerns about the comeback of vaccine-preventable diseases. Epidemics exert shocks which affect other health performance indicators such as routine immunizations. Early model forecasts indicate decreased use of immunization services, which puts children at greater risk. Concerns about an increase in morbidity and mortality for il...

Objective To examine the risk of preterm birth (PTB) and small for gestational age (SGA) among women living with HIV compared to women without HIV. Secondary objectives were to explore the role of maternal immune activation (IA) and effect of cART timing on these outcomes. Design Prospective observational cohort. Setting Urban government-run clin...

This study assessed the capacity of selected laboratories to conduct surveillance of antimicrobial resistance in Zambia.

Mutations have driven the evolution and development of new variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with potential implications for increased transmissibility, disease severity and vaccine escape among others. Genome sequencing is a technique that allows scientists to read the genetic code of an organism and has...

Enteric infections due to viral pathogens are a major public health concern. Detecting the risk areas requires a strong surveillance system for pathogenic viruses in sources such as wastewater. Towards building an environmental surveillance system in Zambia, we aimed to identify group A rotavirus (RVA) and human adenovirus (HAdV) in wastewater. Con...

Childhood stunting is associated with impaired cognitive development and increased risk of infections, morbidity, and mortality. The composition of the enteric microbiota may contribute to the pathogenesis of stunting. We systematically reviewed and synthesized data from studies using high-throughput genomic sequencing methods to characterize the g...

Background Antimicrobial resistance (AMR) poses a threat to public health globally. Despite its consequences, there is little information about the knowledge, awareness, and practices towards AMR among healthcare workers (HCWs). Therefore, this study assessed the knowledge, awareness and practices regarding antimicrobial use (AMU), AMR and antimicr...

Introduction There have been few empirical studies for diagnostic test accuracy of syphilis using a sequence of rapid tests in populations with low prevalence of syphilis such as pregnant women. This analysis describes syphilis test positivity frequency among pregnant women at an antenatal clinic in Zambia using a reverse-sequence testing algorithm...

Background The number of COVID-19 deaths reported in Zambia (N=4,069) is most likely an underestimate due to limited testing, incomplete death registration and inability to account for indirect deaths due to socioeconomic disruption during the pandemic. We sought to assess excess mortality during the COVID-19 pandemic in Zambia. Methods We conducte...

Despite ongoing containment and vaccination efforts, cholera remains prevalent in many countries in sub-Saharan Africa. Part of the difficulty in containing cholera comes from our lack of understanding of how it circulates throughout the region. To better characterize regional transmission, we generated and analyzed 118 Vibrio cholerae genomes coll...

Deaths from COVID-19 likely exceeded official statistics in Zambia because of limited testing and incomplete death registration. We describe a sentinel COVID-19 mortality surveillance system in Lusaka, Zambia. We analyzed surveillance data on deceased persons of all ages undergoing verbal autopsy (VA) and COVID-19 testing at the University Teaching...

This study aimed to estimate the incidence and risk factors for Enterotoxigenic Escherichia coli (ETEC) diarrhea. This was a prospective cohort study of children recruited in a household census. Children were enrolled if they were 36 months or below. A total of 6828 children were followed up passively for 12 months to detect episodes of ETEC diarrh...

Oral rotavirus vaccines demonstrate diminished immunogenicity in low-income settings where human cytomegalovirus infection is acquired early in childhood and modulates immunity. We hypothesized that human cytomegalovirus infection around the time of vaccination may influence immunogenicity. We measured plasma human cytomegalovirus-specific immunogl...

Enteric infections are a major public health concern. Detecting risk areas requires a strong surveillance system for pathogenic viruses in possible sources such as wastewater. To build an environmental surveillance system, we aimed to identify group A rotavirus (RVA) and human adenovirus (HAdV) in wastewater. We also focused on three different meth...

Background: Acute diarrhoea is a major cause of morbidity and mortality among children in low-resource settings. Establishing effective surveillance systems is crucial for monitoring and responding to diarrhoeal outbreaks. Objective: This manuscript presents the lessons learned during the setup of a hospital-based diarrhoea surveillance system at A...

Objectives This study assessed antibiotic prescribing patterns in primary healthcare facilities and antimicrobial resistance (AMR) profiles of commensal Escherichia coli and enterococci isolated from pregnant women and children under 5 years of age. Materials and methods This cross-sectional study was conducted in Lusaka and Ndola districts of Zam...

Diarrhoeagenic E. coli (DEC) significantly contributes to the burden of diarrhoea among children. Currently, there is no approved vaccine against DEC, but several vaccines against the enterotoxigenic E. coli (ETEC) pathotype are in advanced clinical trial stages, including the ETVAX® vaccine, undergoing evaluation in Zambia. This study reports on t...

Objectives The study aim was to evaluate vaccine effectiveness (VE) of COVID-19 vaccines in preventing symptomatic COVID-19 among healthcare workers (HCWs) in Zambia. We sought to answer the question, ‘What is the vaccine effectiveness of a complete schedule of the SARS-CoV-2 vaccine in preventing symptomatic COVID-19 among HCWs in Zambia?’ Design...

The occurrence of rotavirus (RV) infection among vaccinated children in high-burden settings poses a threat to further disease burden reduction. Genetically altered viruses have the potential to evade both natural infection and vaccine-induced immune responses, leading to diarrheal diseases among vaccinated children. Studies characterizing RV strai...

Citation: Mwape, K.; Bosomprah, S.; Chibesa, K.; Silwamba, S.; Luchen, C.C.; Sukwa, N.; Mubanga, C.; Phiri, B.; Chibuye, M.; Liswaniso, F.; et al. Prevalence of Diarrhoeagenic Escherichia coli among Children Aged between 0-36 Months in Peri-Urban Areas of Lusaka. Microorganisms 2023, 11, 2790. https://doi. Abstract: Diarrhoea is a major contributor...

Background Rotavirus gastroenteritis remains a leading cause of morbidity and mortality despite the introduction of vaccines. Research shows there are several factors contributing to the reduced efficacy of rotavirus vaccines in low- and middle-income settings. Proposed factors include environmental enteric dysfunction (EED), malnutrition, and immu...

The significance of Epstein-Barr virus (EBV) detection in the cerebrospinal spinal fluid (CSF) in people living with HIV (PLWH) is not entirely understood. The detection of EBV DNA may represent active central nervous system (CNS) infection, reactivation in the setting of another CNS pathogen or due to impaired immunity, or detection of quiescent v...

The circulation of bothWest Nile Virus (WNV) and Chikungunya Virus (CHIKV) in humans and animals, coupled with a favorable tropical climate for mosquito proliferation in Zambia, call for the need for a better understanding of the ecological and epidemiological factors that govern their transmission dynamics in this region. This study aimed to exami...

Introduction While tremendous progress has been made in recent years to improve the health of people living in low- and middle-income countries (LMIC), significant challenges remain. Chief among these are poor health systems, which are often ill-equipped to respond to current challenges. It remains unclear whether intensive intervention at the heal...

Citation: Chauwa, A.; Bosomprah, S.; Laban, N.M.; Phiri, B.; Chibuye, M.; Chilyabanyama, O.N.; Munsaka, S.; Simuyandi, M.; Mwape, I.; Mubanga, C.; et al. Maternal and Infant Histo-Blood Group Antigen Profiles and Their Influence on Oral Rotavirus Vaccine Immunogenicity among Infants in Zambia. Vaccines 2023, 11, 1303. https://doi. Abstract: Live-at...

The emergence of pre-extensively drug-resistant tuberculosis (pre-XDR-TB) is a threat to TB control programs in developing countries such as Zambia. Studies in Zambia have applied molecular techniques to understand drug-resistance-associated mutations, circulating lineages and transmission patterns of multi-drug-resistant (MDR) Mycobacterium tuberc...

Background Inappropriate antimicrobial usage is a key driver of antimicrobial resistance (AMR). Low- and middle-income countries (LMICs) are disproportionately burdened by AMR and young children are especially vulnerable to infections with AMR-bearing pathogens. The impact of antibiotics on the microbiome, selection, persistence, and horizontal spr...

Live-attenuated, oral rotavirus vaccines have significantly reduced rotavirus-associated diarrhoea morbidity and infant mortality. However, vaccine immunogenicity is diminished in low-income countries. We investigated whether maternal and infant intrinsic susceptibility to rotavirus infection via histo-blood group antigen (HBGA) profiles influenced...

Tuberculosis before the COVID-19 pandemic is said to have killed more people globally than any other communicable disease and is ranked the 13th cause of death, according to the WHO. Tuberculosis also still remains highly endemic, especially in LIMCs with a high burden of people living with HIV/AIDS, in which it is the leading cause of mortality. G...

Citation: Mubanga, C.; Simuyandi, M.; Mwape, K.; Chibesa, K.; Chisenga, C.; Chilyabanyama, O.N.; Randall, A.; Liang, X.; Glashoff, R.H.; Chilengi, R. Use of an ETEC Proteome Microarray to Evaluate Cross-Reactivity of ETVAX ® Abstract: Developing a broadly protective vaccine covering most ETEC variants has been elusive. The most clinically advanced...

Background: Diarrhoeal disease is a leading cause of childhood illness and death globally, and Shigella is a major aetiological contributor for which a vaccine might soon be available. The primary objective of this study was to model the spatiotemporal variation in paediatric Shigella infection and map its predicted prevalence across low-income an...

Background Shigella is a leading cause of bacterial diarrhea morbidity and mortality affecting mainly children under five in the developing world. In Zambia, Shigella has a high prevalence of 34.7% in children with diarrhea and an attributable fraction of 6.7% in Zambian children with moderate to severe diarrhea. Zambian diarrhea management guideli...

Introduction: Hepatitis B virus (HBV) is highly infectious and deadly disease that is transmitted through blood and body fluids. Health care workers (HCWs) have a high risk of contracting HBV in health care settings, the Hep-B vaccine one of the recommended prevention intervention/tools. However, uptake of the vaccine among HCWs remains low in Sub...

Citation: Laban, N.M.; Bosomprah, S.; Simuyandi, M.; Chibuye, M.; Chauwa, A.; Chirwa-Chobe, M.; Sukwa, N.; Chipeta, C.; Velu, R.; Njekwa, K.; et al. Evaluation of ROTARIX ® Booster Abstract: Oral rotavirus vaccines show diminished immunogenicity in low-resource settings where rotavirus burden is highest. This study assessed the safety and immune bo...

Background Histo-blood group antigens (HBGAs) which include the ABO and Lewis antigen systems have been known for determining predisposition to infections. For instance, blood group O individuals have a higher risk of severe illness due to V. cholerae compared to those with non-blood group O antigens. We set out to determine the influence that thes...

Introduction Chronic viral replication has been linked to an increased risk of cardiovascular and metabolic diseases in people living with HIV (PLWH), but few studies have evaluated this association in Southern Africa. We explored the determinants of metabolic syndrome (MetS) among treatment-naïve adults living with and without HIV in Southern Afri...

Simply detecting Epstein–Barr virus deoxyribonucleic acid (EBV-DNA) is insufficient to diagnose EBV-associated diseases. The current literature around EBV-DNA detection from cerebrospinal fluid (CSF) in human immunodeficiency virus (HIV)-positive non-lymphoma patients was systematically reviewed and a meta-analysis reporting the estimated pooled pr...

During a COVID-19 outbreak in a prison in Zambia from December 14 to 19, 2021, a case–control study was done to measure vaccine effectiveness (VE) against infection and symptomatic infection, when the Omicron variant was the dominant circulating variant. Among 382 participants, 74.1% were fully vaccinated, and the median time since full vaccination...

Background: Moraxella catarrhalis is one of the bacterial pathogens associated with childhood pneumonia, but its clinical importance is not clearly defined. Objective: This study aimed to investigate the microbiologic and virulence characteristics of M. catarrhalis isolates obtained from children with pneumonia in Lusaka, Zambia. Methods: This...

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) have significantly impacted the global epidemiology of the pandemic. From December 2020 to April 2022, we conducted genomic surveillance of SARS-CoV-2 in the Southern Province of Zambia, a region that shares international borders with Botswana, Namibia, and Zimb...

Background Diarrhoeal disease remains a leading cause of death among children mostly in low and middle-income countries. Factors contributing to disease severity are complex and there is currently no consensus on a scoring tool for use in community-based studies. Methods Data were collected during a passive surveillance system in an outpatient hea...

Background Enterotoxigenic Escherichia coli (ETEC) is one of the top aetiologic agents of diarrhea in children under the age of 5 in low-middle income countries (LMICs). The lack of point of care diagnostic tools for routine ETEC diagnosis results in limited data regarding the actual burden and epidemiology in the endemic areas. We evaluated perfor...

Introduction The growing importance of non-communicable diseases (NCDs) and high HIV prevalence in urban African settings may increase the burden of metabolic dysfunction-associated fatty liver disease (MAFLD). We assessed liver steatosis among HIV-positive and negative adults in urban Zambia. Methods Adults 30 years and older who were newly diagn...

Introduction Antimicrobial resistance (AMR) is a growing public health problem in low-to-middle income countries which have a high burden of infectious diseases. Poor antimicrobial stewardship in these regions has resulted in a rise in reported cases of AMR creating a need for country specific data to inform policy on the strategies of combating AM...

During a COVID-19 outbreak in a prison in Zambia from 14 th to 19 th December 2021, a case control study was done to measure vaccine effectiveness (VE) against infection and symptomatic infection, when the Omicron variant was the dominant circulating variant. Among 382 participants, 74.1% were fully vaccinated and the median time since full vaccina...

Human challenge studies are instrumental for testing cholera vaccines, but these studies use outdated strains and require inpatient facilities. Here, we created next-generation isogenic Ogawa and Inaba O1 V. cholerae challenge strains (ZChol strains) derived from a contemporary Zambian clinical isolate representative of current dominant pandemic V....

Background Enterotoxigenic Escherichia coli (ETEC) is one of the top aetiologic agents of diarrhea in children under the age of 5 in low-middle income countries (LMICs). The lack of point of care diagnostic tools for routine ETEC diagnosis results in limited data regarding the actual burden and epidemiology in the endemic areas. We evaluated perfor...

Cellular immunity against rotavirus in children is incompletely understood. This review describes the current understanding of T-cell immunity to rotavirus in children. A systematic literature search was conducted in Embase, MEDLINE, Web of Science, and Global Health databases using a combination of "t-cell", "rotavirus" and "child" keywords to ext...

Introduction In cholera endemic areas, the periodicity of cholera outbreaks remains unpredictable, making it difficult to organize preventive efforts. Lack of data on duration of protection conferred by oral cholera vaccines further makes it difficult to determine when to deploy preemptive vaccination. We report on the immunogenicity and waning of...

Human challenge studies are instrumental for testing cholera vaccines, but these studies use outdated strains and require inpatient facilities. Here, we created next-generation isogenic Ogawa and Inaba V. cholerae challenge strains (ZChol strains) derived from a contemporary Zambian clinical isolate representative of current dominant pandemic V. ch...