FY 2014 AMD Projects: Analyzing Emerging Epidemics

Whole genome sequencing to assess epidemic potential of emerging meningococcal strains and monitor changes in vaccine immunogen and virulence-related genes

A bottle of the meningitis vaccine sits on a table in the foreground. Several African patients wait in the background.

The Meningitis Vaccine Project partners hope to vaccinate some 300 million people throughout the African 'meningitis belt' by 2015, thereby ridding the region of a disease that has caused havoc for more than a century.

Bacterial meningitis (meningococcal disease) kills 1 in 10 patients within 48 hours, even when antibiotics are started early. Patients that survive often have permanent disabilities like paralysis, blindness, hearing loss, or seizures. Meningococcal disease threatens the lives of millions of people across sub-Saharan Africa’s “meningitis belt.”

A vaccine (MenAfriVac) was introduced in 2010 to prevent the most common strain of meningococcal disease in Africa (serogroup A). But even with this vaccine still many questions and challenges remain. For instance, what if other strains in circulation in the region (serogroups X and W) start causing more disease? Evidence already suggests that this may be happening. How dangerous are those strains? Are they genetically linked to other strains? And most important, are currently available vaccines effective against these other strains?

To answer these questions, CDC is using whole genome sequencing analysis on hundreds of African meningococci specimens. CDC will compare these specimens to strains causing sporadic disease and other outbreaks worldwide. Using new tools, CDC’s laboratory scientists will compare how closely related the strains are and find markers for how likely they are to cause epidemics.

Using whole genome sequencing analysis, meningitis experts will be more effective in predicting meningococcal disease epidemics at an early stage and know if available vaccines are effective against these strains.

This vital information will help ministries of health and policy makers in structuring vaccination decisions and maximize public health response.

PRINCIPAL INVESTIGATOR PROFILE

Xin Wang, PhD

Acting Chief, Meningitis Laboratory
Meningitis and Vaccine Preventable Diseases Branch
Division of Bacterial Diseases
National Center for Immunization and Respiratory Diseases

Xin Wang, PhD is the acting chief of the Meningitis Laboratory within the Division of Bacterial Diseases’ Meningitis and Vaccine Preventable Diseases Branch in CDC’s National Center for Immunization and Respiratory Diseases.

In this role, Wang serves as an expert on multiple subjects, including molecular diagnostics, molecular epidemiology, and genetic diversity of vaccine immunogens. She led the development of a breakthrough method for rapidly detecting bacterial pathogens that cause meningitis and threaten the lives of millions of people across Africa’s meningitis belt.

Wang is directing a whole genome sequencing study to identify genetic markers for strains of serogroup W Neisseria meningitidis that have caused epidemics in different parts of the world. By genetically comparing the serogroup W strains currently circulating in Africa to those known to cause outbreaks, scientists will be able to see if the African strains are a serious public health concern. She is also conducting a similar research study to see how different strains of these bacteria are genetically changing now that a serogroup A vaccine was successfully introduced in multiple African countries since 2010.

Wang is a graduate of Shandong University Department of Microbiology and earned her PhD from the Emory University Department of Microbiology and Immunology. In 2014, her contributions were recognized by receipt of the Excellence in Public Health Protection Award and a Special Act or Service Award for laboratory outbreak investigations from CDC’s National Center for Immunization and Respiratory Diseases. She has co-authored more than 40 scientific articles.

PRINCIPAL INVESTIGATOR PROFILE

Conrad P. Quinn, PhD

Chief, Meningitis and Vaccine Preventable Diseases Branch
Division of Bacterial Diseases
National Center for Immunization and Respiratory Diseases

Conrad Quinn, PhD is the chief of the Division of Bacterial Diseases’ Meningitis and Vaccine Preventable Diseases Branch in CDC’s National Center for Immunization and Respiratory Diseases.

With more than 22 years of experience in bacterial infectious disease research, Quinn’s expertise focuses on how the immune system responds to pertussis, meningococcal disease, and anthrax. One of Quinn’s current projects includes searching for pathogen-associated molecular patterns, structures at the cellular level that allow the body to recognize and fight bacterial infections.

Quinn has a proven record in developing clinical, nonclinical, and biomarker discovery programs. He is working to develop ways to quickly test for and identify bacterial infections, as well as finding measurable signs (immune correlates of protection) that a person is protected against disease.

With extensive experience in anthrax vaccine development and evaluation, Quinn now oversees efforts to understand how current pertussis vaccines work against strains of Bordetella pertussis lacking pertactin. Acellular pertussis vaccines are made of inactivated parts of the bacteria and pertactin is one part found in all of today’s vaccines. The findings will inform the development of new pertussis vaccines and help CDC control pertussis in the United States.

Quinn completed his Bachelor of Science in Applied Biology at the University of Wales, Institute of Science and Technology, and earned his PhD in microbiology from the University of Wales, College of Cardiff. He has co-authored 90 scientific publications. Quinn is a member of the Elsevier ‘Council of 100’ and the ATCC Standards Development Organization.