Take on Typhoid Newsletter June 2022

See past issues in our Newsletter Archives

In this issue:

Nepal introduces typhoid conjugate vaccine

A young child sits with friends after receiving TCV as
part of Nepal’s vaccination campaign. Photo: PATH/Rocky Prajapati

Nepal introduced typhoid conjugate vaccine (TCV) in April, beginning with a 3-week campaign to reach 7 million children aged 15 months to 15 years old at 50,000 vaccination sites across the country. Nepal has one of the highest typhoid burdens in the world, with increasing rates of drug-resistant typhoid. The introduction of this vaccine is a key step in reducing Nepal’s typhoid burden and a major milestone toward protecting children from this disease.

Following the campaign, Nepal is transitioning to routine immunization where TCV will be given to all children at 15 months of age. To support this transition to routine immunization, Ashata Dahal from The Oxford University Clinical Research Unit in Nepal developed an animated video on typhoid disease, prevention, diagnosis, and appropriate treatment. This video will help raise awareness about typhoid disease and the vaccine in Nepali communities and provides local, contextual information to support the acceptance of this health intervention.

New data on typhoid burden in Asia

The Lancet Microbe recently published Phase II results of the Surveillance for Enteric Fever in Asia Project (SEAP). Beginning in 2015, the Sabin Vaccine Institute established a hybrid typhoid surveillance study conducted in Bangladesh, Nepal, and Pakistan.

Phase I of SEAP helped establish baseline data on the burden of enteric fever in South Asia and informed the World Health Organization’s (WHO) 2018 revised position paper on typhoid vaccination. Phase II initial results found that while typhoid incidence decreased slightly from 2016-2019, drug resistance is on the rise. Also, most typhoid cases are still not being detected by local health care systems—reflecting the need for lower-cost diagnostics.

The Phase II study measured clinical and community typhoid burden and found high incidence among children, emphasizing the need for TCV immunization as early as 6 months old. The results reiterate the benefits of TCV introduction, along with other typhoid prevention and control measures such as improvements in water and sanitation infrastructure, in these high burden countries, two of which have already introduced TCV.

New TCVs make advancements in the pipeline

Two new TCVs have made significant recent advances. In May, a Phase 3 study of a TCV candidate called EuTCV launched in Sandiara, Senegal. Investigators at theInstitut de Recherche en Santé de Surveillance Epidemiologique et de Formation, Senegal, PATH and EuBiologics are conducting the study to assess the safety and immune response of EuTCV in adults and young children 6 months of age and older. A second site in Kericho, Kenya—in partnership with the Kenya Medical Research Institute-Kericho and Walter Reed Army Institute for Research—is expected to begin in the coming months. The multicenter trial will last two years. EuBiologics will seek WHO prequalification concurrently with the trial, with the results helping to meet post-prequalification data requirements.

Additionally in May, SKYTyphoid, a TCV developed jointly by the International Vaccine Institute and SK bioscience, was licensed by the Korean Ministry of Food and Drug Safety. SKYTyphoid has demonstrated non-inferiority to a prequalified TCV, with a single dose providing protection. The vaccine will be available to infants in Korea younger than age two, and SK bioscience is also seeking WHO prequalification for SKYTyphoid.

With Typbar TCV® and TYPHIBEV® already WHO-prequalified, SKYTyphoid and EuTCV nearing prequalification, and several other TCVs in the pipeline, the TCV market is growing. This growth brings the potential to increase supply, reduce costs, and improve availability of these lifesaving vaccines.

Presentations from the 12th International Conference on Typhoid and Other Invasive Salmonelloses available

Presentations from the 12th International Conference on Typhoid and Other Invasive Salmonelloses are now available to stream. With more than 25 sessions, workshops, and roundtables, 2021’s virtual conference brought together more than 400 researchers and experts for discussion of the latest scientific updates and lively networking and partnership-building. The conference featured panels and presentations from 6 continents and focused on typhoid surveillance and research; prevention (including TCV and WASH); diagnosis; and enteric fever more broadly (including iNTS).

Merryn Voysey, UK Australian of the Year

“Statisticians don’t normally win awards like this; we typically sit in a back office—unobserved,” says Merryn Voysey, University of Oxford Associate Professor of Statistics and lead statistician for the Oxford Vaccine Group, recipient of the 2022 Australian of the Year in the UK award.


Dr. Voysey receives the UK Australian of the Year award.
Photo: Albert Palen

Professor Voysey was honored for her stellar career in vaccinology and work on the Oxford/AstraZeneca vaccine studies, but the story doesn’t stop there. She is also the lead statistician for the TCV study in Nepal. Clinical studies involve collecting mountains of data. We are grateful to Merryn for her guidance and insight designing and analyzing the data. TyVAC is immensely proud to have her on our team!

Scientific publications

Incidence of typhoid and paratyphoid fever in Bangladesh, Nepal, and Pakistan: Results of the Surveillance for Enteric Fever in Asia Project

Effectiveness of typhoid conjugate vaccine in Zimbabwe used in response to an outbreak among children and young adults: A matched case control study

Water sanitation in Karachi and its impact on health

Spatial-temporal and phylogenetic analyses of epidemiologic data to help understand the modes of transmission of endemic typhoid fever in Samoa

Community-level interventions for mitigating the risk of waterborne diarrheal diseases: A systematic review

Prevention of typhoid fever by existing improvements in household water, sanitation, and hygiene, and the use of the Vi polysaccharide typhoid vaccine in poor urban slums: Results from a cluster-randomized trial

Risk factors associated with extensively drug-resistant typhoid in an outbreak setting of Lyari Town Karachi, Pakistan

Visit our publications page for more recent research

Protecting Rohingya refugees through WASH and vaccines

Pediatricians are key advocates in the fight against typhoid

EuTCV trial begins in Senegal

Community engagement to increase trust in vaccines: Lessons from a TCV study in Nepal

Improved WASH plus TCV shown to further reduce typhoid in Bangladesh

A typhoid-free life: Portraits of TCVs

Vaccine reaches Nepal’s provinces just in time for typhoid season

Celebrating Nepal’s typhoid conjugate vaccine introduction

Tracking the health impact of Tropical Storm Ana

Previous posts available on the blog