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Senior Scientist
Maria Knoll

Departmental Affiliations

Global Disease Epidemiology and Control

Center & Institute Affiliations

Maria Deloria Knoll, PhD ’00, designs, conducts, and analyzes policy-driven epidemiological studies and clinical trials evaluating vaccines and vaccine-preventable diseases.

Contact Info

415 N. Washington Street, Room 549

Research Interests

vaccines; international health; COVID-19; SARS-CoV-2; S. Pneumoniae; H. influenzae; RSV; meningococcus; HPV; pertussis; pneumonia; meningitis; vaccine preventable diseases; epidemiology; clinical trials; meta-analysis; pneumonia etiology; disease burden; vaccine impact; pneumococcal conjugate vaccine
Experiences & Accomplishments
Johns Hopkins University
University of North Carolina, Chapel Hill
As the Director of Epidemiology at the International Vaccine Access Center (IVAC), I focus on policy-driven research evaluating vaccines and vaccine-preventable diseases. I often work closely with colleagues at other organizations, particularly at WHO, CEPI and Gavi, the Vaccine Alliance.

Projects include: global tracking and review of COVID-19 vaccine effectiveness to support WHO and CEPI policy decisions; assessing factors associated with COVID-19 disease and transmission in Maryland households; evaluating the impact of introducing pneumococcal conjugate vaccine (PCV) into childhood national immunization programs on pneumococcal disease, including indirect effects on adults; synthesizing evidence through meta-analytical and modeling approaches to estimate global disease burden, serotype distribution and vaccine impact globally for vaccine-preventable diseases (e.g., pneumococcal, Hib, meningococcal and pertussis) among children and adults; evaluating impact of vaccine dosing schedule, age at immunization and product choice to inform WHO policy recommendations and country decision-making; determining the causes of pneumonia in low- and middle-income settings in Africa and Asia to guide development of new pneumonia vaccines and treatment algorithms: the PERCH 7-country case-control study; evaluating new diagnostic tools such as antigen-based blood tests and pneumococcal serotype-specific urine antigen tests to determine their sensitivity and specificity for identifying pneumococcal disease in pneumonia patients; developing and assessing digital tools to assist in the standardization of clinical findings of pneumonia, such as digital auscultation and computer automated chest x-ray interpretation; direct VIEW-hub, a publicly available and interactive data visualization platform displaying vaccine introduction, coverage, access, impact, disease burden data and impact studies globally.
Honors & Awards
Food and Drug Administration Commissioner’s Special Citation Group Award (1997)
U.S. DHHS Secretary’s Group Award for Distinguished Service (1996)
U.S. DHHS Special Achievement Award (1995,1991)
National Institutes of Health Merit Award (1999,1991)
Select Publications
Selected representative publications:
  • Deloria Knoll M, Bennett JC, Garcia Quesada M, Kagucia EW, Peterson ME, Feikin DR, Cohen AL, Hetrich MK, Yang Y, Sinkevitch JN, Ampofo K, Aukes L, Bacci S, Bigogo G, Brandileone M-CC, Bruce MG, Camilli R, Castilla J, Chan G, Chanto Chacón G, Ciruela P, Cook H, Corcoran M, Dagan R, Danis K, de Miguel S, De Wals P, Desmet S, Galloway Y, Georgakopoulou T, Hammitt LL, Hilty M, Ho P-L, Jayasinghe S, Kellner JD, Kleynhans J, Knol MJ, Kozakova J, Kristinsson KG, Ladhani SN, Lara CS, León ME, Lepp T, Mackenzie GA, Mad’arová L, McGeer A, Mungun T, Mwenda JM, Nuorti JP, Nzoyikorera N, Oishi K, De Oliveira LH, Paragi M, Pilishvili T, Puentes R, Rafai E, Saha SK, Savrasova L, Savulescu C, Scott JA, Scott KJ, Serhan F, Setchanova LP, Sinkovec Zorko N, Skoczy?ska A, Swarthout TD, Valentiner-Branth P, van der Linden M, Vestrheim DF, von Gottberg A, Yildirim I, Hayford K, the PSERENADE Team. Global Landscape Review of Serotype-Specific Invasive Pneumococcal Disease Surveillance among Countries Using PCV10/13: The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) Project. Microorganisms. 2021; 9(4):742.
  • Deloria Knoll M, Prosperi C, Baggett HC, Brooks WA, Feikin DR, Hammitt LL, Howie SRC, Kotloff KL, Madhi SA, Murdoch DR, Scott JAG, Thea DM, O'Brien KL. Introduction to the Site-specific Etiologic Results From the Pneumonia Etiology Research for Child Health (PERCH) Study. Pediatr Infect Dis J. 2021 Sep 1;40(9S):S1-S6. doi: 10.1097/INF.0000000000002778. PubMed PMID: 34448739.
  • Wahl B, O’Brien KL, Greenbaum A, Liu L, Chu Y, Majumder A, Lukši? I, Nair H, McAllister DA, Campbell H, Rudan I, Black R, Knoll MD. Global, regional, and national burden of Streptococcus pneumoniae and Haemophilus influenzae type b in children in the era of conjugate vaccines: updated estimates from 2000-2015. Lancet Global Health 2018; 6: e744–e757.
  • Deloria Knoll M, Fu W, Shi Q, Prosperi C, Wu Z, Hammitt LL, Feikin DR, Baggett HC, Howie SRC, Scott JAG, Murdoch DR, Madhi SA, Thea DM, Brooks WA, Kotloff KL, Li M, Park DE, Lin W, Levine OS, O’Brien KL, Zeger SL. Bayesian estimation of pneumonia etiology: epidemiologic considerations and applications to pneumonia etiology research for child health study. Clin Infect Dis 2017; 64(suppl 3):S213–27.
  • Higdon M, Baidya A, Walter KK, Patel MK, Issa H, Espié E, Feikin DR, Deloria Knoll M. Duration of effectiveness of vaccination against COVID-19 disease and infection caused by omicron variant of concern. The Lancet Infectious Diseases. 2022; 22: 1114–1116. doi: 10.1016/S1473-3099(22)00409-1
Developing Bayesian analytical approaches to estimation of pneumonia etiology
PREVAIL: Pneumonia Research and Vaccine Impact League
PCV Technical Coordination with WHO
Hib and pneumococcal disease burden estimation in China
Maternal and Child Epidemiology Estimation (MCEE) collaboration: Global and national pneumococcal, Hib and pertussis etiology estimates
Sustaining Access for Vaccines in India (SAVI)
Baltimore City Influenza Vaccine Initiative Evaluation
PCV Impact in Nepal
SEARCh: SARS-CoV-2 household transmission in Maryland
VIEW-Hub: website tracking globally vaccine introduction, coverage and impact studies
PERCH: etiology of pneumonia in 7 African and Asian countries
COVID-19 Vaccine Effectiveness: global review
Global Impact of PCV on invasive pneumococcal disease in all ages (PSERENADE)