PLOS Global Public Health (Jan 2024)

Attrition in serum anti-DENV antibodies correlates with high anti-SARS-CoV-2 IgG levels and low DENV positivity in mosquito vectors-Findings from a state-wide cluster-randomized community-based study in Tamil Nadu, India.

  • Sivaprakasam T Selvavinayagam,
  • Sathish Sankar,
  • Yean K Yong,
  • Abdul R Anshad,
  • Samudi Chandramathi,
  • Anavarathan Somasundaram,
  • Sampath Palani,
  • Parthipan Kumarasamy,
  • Roshini Azhaguvel,
  • Ajith B Kumar,
  • Sudharshini Subramaniam,
  • Manickam Malathi,
  • Venkatachalam Vijayalakshmi,
  • Manivannan Rajeshkumar,
  • Anandhazhvar Kumaresan,
  • Ramendra P Pandey,
  • Nagarajan Muruganandam,
  • Natarajan Gopalan,
  • Meganathan Kannan,
  • Amudhan Murugesan,
  • Pachamuthu Balakrishnan,
  • Siddappa N Byrareddy,
  • Aditya P Dash,
  • Vijayakumar Velu,
  • Marie Larsson,
  • Esaki M Shankar,
  • Sivadoss Raju

DOI
https://doi.org/10.1371/journal.pgph.0003608
Journal volume & issue
Vol. 4, no. 11
p. e0003608

Abstract

Read online

The decline in dengue incidence and/or prevalence during the COVID-19 pandemic (2020-22) appears to be attributed to reduced treatment-seeking rates, under-reporting, misdiagnosis, disrupted health services and reduced exposure to mosquito vectors due to prevailing lockdowns. There is limited scientific data on dengue virus (DENV) disease during the COVID-19 pandemic. Here, we conducted a community-based, cross-sectional, cluster-randomized survey to assess anti-DENV and anti-SARS-CoV-2 seroprevalence, and also estimated the spatial distribution of DENV-positive aedine mosquito vectors during the COVID-19 pandemic across all the 38 districts of Tamil Nadu, India. Using real-time PCR, the prevalence of DENV in mosquito pools during 2021 was analyzed and compared with the previous and following years of vector surveillance, and correlated with anti-DENV IgM and IgG levels in the population. Results implicate that both anti-DENV IgM and IgG seroprevalence and DENV positivity in mosquito pools were reduced across all the districts. A total of 13464 mosquito pools and 5577 human serum samples from 186 clusters were collected. Of these, 3.76% of the mosquito pools were positive for DENV. In the human sera, 4.12% were positive for anti-DENV IgM and 6.4% for anti-DENV IgG. While the anti-SARS-CoV-2 levels significantly correlated with overall DENV seropositivity, COVID-19 vaccination status significantly correlated with anti-DENV IgM levels. The study indicates a profound impact of anti-SARS-CoV-2 levels on DENV-positive mosquito pools and seropositivity. Continuous monitoring of anti-DENV antibody levels, especially with the evolving variants of SARS-CoV-2 and the surge in COVID-19 cases will shed light on the distribution, transmission and therapeutic attributes of DENV infection.