Typhoid is endemic across much of Africa, causing a high burden of illness and loss of life, and until now there has not been a suitable vaccine for children under two years of age. Typhoid conjugate vaccines (TCV) are a new generation of typhoid vaccines that have not been previously studied on the African continent. Malawi has made history by becoming the first site in Africa to study the efficacy of TCV.

In this study, 28,130 healthy children aged 9 months to 12 years were randomized and vaccinated, making it the biggest of its kind to ever be conducted in Blantyre. The results from the typhoid vaccine study in Malawi demonstrated a TCV vaccine efficacy of 81-84% after 18-24months. This study has shown that the TCV works to prevent typhoid fever in African children from 9 months to 12 years old. It also showed that the vaccine is highly immunogenic, making high levels of antibodies in all age groups and that it has an excellent safety profile.

Director of Health Services for Blantyre, Dr. Gift Kawalazira has described TVC as “truly a game-changer in principal and practice”. “TCV will minimize chances of under diagnosing typhoid at the Primary Health care level and avoid unnecessary complications and death as it (typhoid) can easily be mistaken for Malaria, which is the top cause of morbidity in patients over 5 years of age”, he explained.

He also said that another important advantage of TVC is that it can protect the community from drug-resistant S. typhi strains. “The Health system at the Primary Health care level has weak control measures on the use of antibiotics; as a result, chances of communities harboring drug-resistant S. typhi strains are high”.

 

 

The lead researcher in the trial, Prof. Melita Gordon of the Malawi Liverpool Wellcome Programme and the University of Liverpool echoes Dr. Kawalazira’s sentiments.

“Our only real option to controlling these new resistant strains of typhoid in a timely way is through the vaccine. The TCV efficacy data are the first from Africa and offer great promise for the control of this deadly disease across the continent. Significantly, this vaccine is a great tool not only to control typhoid disease itself but also to combat the international spread of antimicrobial resistance.”

The study is ongoing until September 2021 to see if TCV has equal efficacy in all age groups, including the youngest children, and whether it provides long-term protection. Malawi is in a very unique position as it is the only country currently conducting this trial globally making it the only country that can provide this important information.

This study is part of the Typhoid Vaccine Acceleration Consortium (TyVAC), funded by the Bill and Melinda Gates Foundation. A dollar spent on a childhood vaccination not only helps save a life, but greatly reduces spending on the cost of the illness, reduces the wider societal impacts of disease such as loss of schooling for children, and reduces stress on future health care services. 

Malawi Liverpool Wellcome Programme (MLW), the host of the study, is a proud partner of the Ministry of Health. This has been part of an important journey in making an application to GAVI, the Vaccine Alliance to support the national roll-out of TCV and prevent the high incidence of typhoid in Malawi. Malawi now plans the national introduction of TCV in 2022 – this will include a mass vaccination campaign for all children from 9 months to 15 years, followed by a national introduction into routine Expanded Programme for Immunisation (EPI), co-administered with measles vaccine at the age of 9 months.

“We look forward to the national roll-out in Malawi in 2022, with a mass campaign and introduction into the EPI. Malawi and the rest of Africa needed this vaccine yesterday, and we are thrilled to have a safe effective vaccine now,” said Dr. Queen Dube, Chief of Health Services in Malawi Ministry of Health.

A link to the paper detailing the study is published in the New England Journal of Medicine here.