Ritwik Bhaduri

2020 · medRxiv

Reconciling epidemiological models with misclassified case-counts for SARS-CoV-2 with seroprevalence surveys: a case study in Delhi, India

Rupam Bhattacharyya, Ritwik Bhaduri, Ritoban Kundu, Maxwell Salvatore, et al.

medRxiv preprint

Abstract

Underreporting of COVID-19 cases and deaths is a hindrance to correctly modeling and monitoring the pandemic. This is primarily due to limited testing, lack of reporting infrastructure, and a large number of asymptomatic infections. In addition, diagnostic tests (RT-PCR tests for detecting current infection) and serological antibody tests for IgG (to assess past infections) are imperfect—in particular, the diagnostic tests have a high false negative rate. Epidemiologic models with a latent compartment for unascertained infections like the SEIR model can provide predictions for unreported cases and deaths under certain assumptions. In this paper, we develop a method to account for high false negative rates in RT-PCR in an extension to the classic SEIR model. We apply this method to Delhi, the national capital region of India, obtaining estimates of the underreporting factor for cases at 34–53 times and for deaths at 8–13 times. Based on a recently released serological survey for Delhi with an estimated 22.86% seroprevalence, we compute adjusted estimates of the true number of infections, yielding an underreporting factor for cases from 30–42, implying approximately 96–98% of cases in Delhi remained unreported.

BibTeX

@misc{bhattacharyya2020reconciling,
  title={Reconciling epidemiological models with misclassified case-counts for {SARS-CoV-2} with seroprevalence surveys: a case study in Delhi, India},
  author={Rupam Bhattacharyya and Ritwik Bhaduri and Ritoban Kundu and Maxwell Salvatore and others},
  year={2020},
  howpublished={medRxiv},
  doi={10.1101/2020.07.31.20166249},
  abstract={Underreporting of COVID-19 cases and deaths is a hindrance to correctly modeling and monitoring the pandemic. We develop a method to account for high false negative rates in RT-PCR in an extension to the classic SEIR model, applying it to Delhi, India. We obtain estimates of the underreporting factor for cases at 34-53 times and for deaths at 8-13 times, largely consistent with the first round of serosurveys for Delhi with an estimated 22.86% seroprevalence, implying approximately 96-98% of cases in Delhi remained unreported.}
}