Impact of the COVID-19 pandemic and TCV introduction on typhoid fever in Nepal

While typhoid conjugate vaccines (TCV) offer promise for reducing risk in endemic settings, their population-level impact remains unclear. In 2022, Nepal introduced TCV nationally on the heels of the COVID-19 pandemic, which disrupted healthcare services, surveillance, and potentially typhoid transmission dynamics, complicating vaccine impact evaluation. We investigated the impact of TCV introduction amid shifting typhoid burden during the pandemic by analyzing blood culture data from four Kathmandu Valley health facilities, comparing culture positivity for Salmonella Typhi across three periods: pre-pandemic (January 2018-March 2020); pandemic, pre-vaccine introduction (April 2020-April 2022); post-vaccine introduction (May 2022-April 2024). S. Typhi blood culture positivity declined sharply during the pandemic before TCV introduction. The subsequent rollout of TCV substantially reduced typhoid burden in vaccine-eligible children; howeve..., , # Data from: Impact of the COVID-19 pandemic and TCV introduction on typhoid fever in Nepal

Dataset DOI: [10.5061/dryad.kprr4xhhj](10.5061/dryad.kprr4xhhj)

## Description of the data and file structure

Blood culture data were collected from four Kathmandu Valley health facilities, which were used to compare culture positivity for *Salmonella* Typhi across three periods: pre-pandemic (January 2018-March 2020); pandemic, pre-vaccine introduction (April 2020-March 2022); post-vaccine introduction (April 2022-April 2024).

## Files and variables

### **File directory**

**\"AggregateCountsbyTime.csv\":** Aggregate counts of total blood cultures (TBC) and total *Salmonella* Typhi and Paratyphi positive results per site by month and year

**\"Deidentified_Individual_Data.csv\":** Individual de-identified data of culture findings

**\"owid-covid-data.xlsx\":** National COVID-19 case data sourced from Our World in Data ([https://ourworldindata.org/covid-cases](https://ourworldindata.org/covid-case..., , **Changes after Jan 13, 2026:** Adding de-identified individual data for reproducibility.