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In this issue:
- TCVs protect children in typhoid- and HIV-endemic countries
- Using genomic surveillance to take on typhoid
- What are we learning about typhoid intestinal perforation?
- 2024 Asia Regional Meeting on Typhoid & TCV
- Thank you Mila
- Updated resources to take on typhoid
- Scientific publications
- Blogs
TCVs protect children in typhoid- and HIV-endemic countries
Human immunodeficiency virus (HIV) exposure in utero can cause impaired immune responses to vaccines in infancy, which can lead to increased risk of illness. A recent study in Malawi found typhoid conjugate vaccines
(TCVs) are safe, effective, and well tolerated in children born to people with HIV, which means these children can be protected from typhoid when they receive the vaccine via the routine immunization schedule in their country. The data are especially important in sub-Saharan Africa, where 90% of children born to people with HIV reside.
In typhoid and HIV co-endemic populations, TCVs hold great promise to take on typhoid and protect all children.
Mother and daughter in Malawi. Credit: CVD.
Using genomic surveillance to take on typhoid
To address the growing challenge of global drug resistance, scientists use genomic surveillance to monitor the emergence and spread of drug-resistant typhoid. A recent publication from researchers at IAVI and Monash University defines genomic surveillance and details how analysis of genomic surveillance data can be used to track specific strains of extensively drug-resistant (XDR) typhoid. Another recent study analyzed typhoid samples from Kenya and found connections between isolates from India, Rwanda, Tanzania, and Uganda, enhancing our understanding of regional and global transmission patterns. Results showed close relatedness of drug-resistant typhoid strains across the five countries, suggesting both local and cross-border transmission. Understanding transmission patterns highlights the importance of effective prevention. Ongoing genomic sequencing furthers our understanding of how drug-resistant S. Typhi spreads so policymakers can make informed decisions about typhoid prevention and control.
What are we learning about typhoid intestinal perforation?
A recent systematic review revealed disability and death associated with typhoid intestinal perforation (TIP) remain substantial in Africa and Asia. The authors estimate 16% of TIP patients die, with a higher percentage in Africa (21%) compared to Asia (6%). While the percentage has been declining since 1980 in Asia, it remains unchanged in Africa. Moreover, almost 20% of children who underwent TIP surgery died in settings with high typhoid incidence, and more than half of TIP patients experience postoperative complications.
Data from this review is one indicator of how severe typhoid is circulating in a community. This information can enable policymakers to make informed decisions about TCV introduction to prevent typhoid, which can also prevent the progression that leads to TIP.
2024 Asia Regional Meeting on Typhoid & TCV
Asia Regional Meeting attendees. Credit: ICMR.
At the end of August, more than 75 attendees, including researchers, policymakers, and National Immunization Technical Advisory Group representatives from 13 countries, gathered in Delhi, India, for the 2024 Asia Regional Meeting on Typhoid & TCV. The event featured a robust agenda focused on highlighting the burden of typhoid and urgent need for TCV introduction. Discussions reiterated that while many countries are making strides in typhoid prevention, significant barriers, such as competing health priorities, financial constraints, and synthesizing available data to support TCV decision-making remain. The meeting offered a platform for shared learning and strategic collaboration and attendees left with a strengthened commitment to continue collaboration, emphasizing the importance of sustained partnerships and ongoing dialogue among countries, policymakers, and global health partners.
Thank you Mila
A heartfelt thank you to Dr. Mila Shakya for her amazing contributions to the typhoid field. Mila managed the TyVAC Nepal site and spearheaded day-to-day activities for the Strategic Alliance for Typhoid across Africa and Asia study in Nepal. She is a dedicated physician-scientist with exceptional analytic capability and communication skills. She first authored the interim and final TyVAC Nepal publications and advocated for TCVs. The data she helped generate were instrumental in Nepal’s decision to introduce TCV. We wish her the best as she moves onto her next position as an Epidemic Intelligence Service
(EIS) Officer at the United States Centers for Disease Control and Prevention. Congratulations Mila!
Dr. Mila Shakya. Credit: CDC.
Updated resources to take on typhoid
Take on Typhoid resources and materials have been updated to incorporate the latest typhoid disease burden estimates, new research, available TCV products, and TCV country introductions. Available materials include fact sheets, infographics, and country-specific tools. French and Portuguese translations are coming soon!
