News & Events

Translational Science: Efficacy of Typhoid Conjugate Vaccine in Malawi

MLW has several translational projects in addition to those that have been funded by the institutional translational partnership Award (iTPA). One such project is the TyVAC trial. This month we talked to Priyanka Patel from the Salmonella and Enterics group to get some updates on the success of the TyVAC trial.

What is the background of the trial?

Typhoid Fever has been an important public health issue across the African continent for approximately a decade. Typhoid is a vaccine preventable disease; however, the previous typhoid vaccine candidates were not widely used, largely due to age restrictions and the need for repeated doses. Vaccines are one of the most cost-effective health care interventions. A dollar spent on childhood vaccination not only helps save a life, but greatly reduces spending on the cost of the illness, the wider societal impacts of disease, and future health care. 

Typhoid conjugate vaccines (TCV) have not been previously tested on the African continent. Malawi has made history by becoming the first site in Africa to study the efficacy of the typhoid conjugate vaccine. The TyVAC trial is part of the Typhoid Vaccine Acceleration Consortium, funded by the Bill and Melinda Gates Foundation.

What is the progress so far?

The vaccine works!!

In this trial, 28,130 healthy children aged 9 months to 12 years were vaccinated, making it the biggest of its kind to ever be conducted in Blantyre. The results from the typhoid vaccine trial in Malawi demonstrated a vaccine efficacy of 81-84% after 18-24 months. This trial has showed that the TCV works to prevent typhoid fever in African children. It also showed that the vaccine is highly immunogenic in all the age groups, and that it has an excellent safety profile. These results are extremely helpful not only for Malawi but for Africa as well. This is a major step in the fight against typhoid!

Informed policy decisions

Malawi Liverpool Wellcome Trust (MLW) has always been a proud partnerof the Ministry of Health and this has been part of an important journey in making an application to GAVI for the National introduction of TCV in Malawi. Exciting news for Malawi is that GAVI has now funded National Introduction of TCV from 2022 – this will include a mass vaccination campaign for all children from 9 months to 15 years, followed by national introduction into routine EPI, co-administered with measles vaccine at the age of 9 months.

What next?

MLW aspires to partner with the Ministry of Health and Ministry of Education to measure the future national impact of TCV vaccination on the burden of typhoid incidence and morbidity in Malawi.

The trial itself is ongoing until Sept 2021 to study if the TCV has equal efficacy in all age groups, including the youngest children, and whether it provides longer term protection. Malawi is currently in a unique position, as it is the only country globally that can provide this important data.