Comparison of Strategies for Typhoid Conjugate Vaccine Introduction in India: A Cost-Effectiveness Modeling Study

Abstract

Background Typhoid fever causes substantial global mortality, with almost half occurring in India. New typhoid vaccines are highly effective and recommended by the World Health Organization for high-burden settings. There is a need to determine whether and which typhoid vaccine strategies should be implemented in India. Methods We assessed typhoid vaccination using a dynamic compartmental model, parameterized by and calibrated to disease and costing data from a recent multisite surveillance study in India. We modeled routine and 1-time campaign strategies that target different ages and settings. The primary outcome was cost-effectiveness, measured by incremental cost-effectiveness ratios (ICERs) benchmarked against India’s gross national income per capita (US$2130). Results Both routine and campaign vaccination strategies were cost-saving compared to the status quo, due to averted costs of illness. The preferred strategy was a nationwide community-based catchup campaign targeting children aged 1–15 years alongside routine vaccination, with an ICER of $929 per disability-adjusted life-year averted. Over the first 10 years of implementation, vaccination could avert 21–39 million cases and save $1.6–$2.2 billion. These findings were broadly consistent across willingness-to-pay thresholds, epidemiologic settings, and model input distributions. Conclusions Despite high initial costs, routine and campaign typhoid vaccination in India could substantially reduce mortality and was highly cost-effective.

Comparison of model predictions of typhoid conjugate vaccine public health impact and cost-effectiveness

“…Our results support other analyses predicting the cost-effectiveness of TCV introduction in India. Using a dynamic compartmental model, Ryckman et al (2021) assessed the cost-effectiveness of different TCV vaccination strategies in India across a 10-year time horizon [48] . Similar to our study, they predicted that, from a healthcare perspective, a routine vaccination plus catch-up campaign strategy would be cost-effective or cost-saving.…”

Programmatic Effectiveness of a Pediatric Typhoid Conjugate Vaccine Campaign in Navi Mumbai, India

“…Our findings support the use of TCV mass vaccination campaigns as an effective population-based tool to reduce the pediatric public health burden of typhoid fever, as part of the introduction of TCV into routine immunization programs. This evaluation adds to the body of research supporting TCV campaigns by demonstrating these campaigns can be effective at the population level, while prior modeling suggests they may be highly cost-effective [40]. Additionally, our experience is in the setting of atypical population healthcare utilization or low reported typhoid incidence, the test-negative design is useful in estimating programmatic campaign effectiveness.…”

Spatial heterogeneity of socio-economic determinants of typhoid/paratyphoid fever in one province in central China from 2015 to 2019

“…Additionally, since most travelers do not receive disease prevention education and vaccination before and after departure [ 30 ], the risk of disease exposure is increased. Typhoid and paratyphoid fever are common in Southeast Asia, among which the burden of typhoid and paratyphoid fever in India is weighty and about half of the global deaths are from India [ 31 ]. As a part of Asia, China should pay attention to the situation of the disease entering from Southeast Asia and do entry-exit quarantine work.…”