Epidemiological evidence of acute transmission of Zika virus infection in dengue suspected patients in Sri-Lanka

Mya Myat Ngwe Tun; Sandra Kendra Raini; Lakkumar Fernando; Yins Gunawardene; Shingo Inoue; Yuki Takamatsu; Takeshi Urano; Rohitha Muthugala; Menaka Hapugoda; Kouichi Morita

doi:10.1016/j.jiph.2023.07.014

Epidemiological evidence of acute transmission of Zika virus infection in dengue suspected patients in Sri-Lanka

J Infect Public Health. 2023 Sep;16(9):1435-1442. doi: 10.1016/j.jiph.2023.07.014. Epub 2023 Jul 23.

Authors

Affiliations

¹ Department of Tropical Viral Vaccine Development, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan; Department of Virology, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan; Center for Vaccines and Therapeutic Antibodies for Emerging Infectious Diseases, Shimane University, Izumo, Japan. Electronic address: myamyat@tm.nagasaki-u.ac.jp.
² Department of Virology, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan.
³ Centre for Clinical Management of Dengue & Dengue Haemorrhagic Fever, District General Hospital, Negombo 11500, Sri Lanka.
⁴ Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, Ragama 11010, Sri Lanka.
⁵ Kenya Research Station, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan.
⁶ Center for Vaccines and Therapeutic Antibodies for Emerging Infectious Diseases, Shimane University, Izumo, Japan.
⁷ Department of Virology, National Hospital Kandy, Kandy 20000, Sri Lanka.
⁸ Department of Tropical Viral Vaccine Development, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan; Department of Virology, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan; DEJIMA Infectious Disease Research Alliance, Nagasaki University, Nagasaki 852-8523, Japan.

PMID: 37517370
DOI: 10.1016/j.jiph.2023.07.014

Abstract

Background: Zika Virus (ZIKV) is a re-emerging, arthropod-borne flavivirus transmitted by Aedes mosquitoes (Ae. aegypti and Ae. albopictus). The coexistence of dengue virus (DENV) and ZIKV concurrently has been associated with a wide array of neurological complications, which may influence the clinical outcomes of infections. Sri Lanka witnessed a severe dengue epidemic in 2017, characterized by extraordinary and severe disease manifestations with considerable morbidity. Therefore, this study assessed the potential occurrence of ZIKV infection during DENV outbreak in Sri Lanka from 2017 to 2019, which could bear substantial implications for public health.

Methods: Five hundred ninety-five serum samples were procured from individuals suspected of dengue and admitted to Kandy National Hospital between 2017 and 2018 and the Negombo District General Hospital between 2018 and 2019. These samples underwent quantitative real-time RT-PCR (qRT-PCR) to identify the presence of the ZIKV gene, while enzyme-linked immunosorbent assay was employed to detect ZIKV-specific IgM and IgG antibodies. Focus reduction neutralization tests were subsequently conducted to confirm ZIKV infection.

Results: Among the 595 serum samples, 6 (1.0%) tested positive for ZIKV using qRT-PCR. Anti-ZIKV IgM and IgG were identified in 18.0% and 38.6% patients. Sixty-six (11.0%) samples demonstrated the presence of anti-ZIKV IgM and IgG. Within ZIKV IgM-positive samples, 2.2% exhibited neutralizing antibodies against ZIKV. Through the implementation of qRT-PCR, ZIKV IgM detection, and neutralization testing, 2% and 3.7% cases of ZIKV infections were confirmed in the Kandy and Negombo regions, respectively.

Conclusion: This study is the inaugural endeavor to substantiate the existence of ZIKV infection in Sri Lanka utilizing molecular and serological analysis. The findings of this investigation imply that ZIKV was circulating throughout the 2017-2019 DENV outbreak. These results underscore the necessity for improved preparedness for future outbreaks, fortifying governmental policies on public health, and establishing effective early warning systems regarding the emergence of these viruses.

Keywords: Acute Zika virus infection; Dengue suspected; Molecular and serological detection; Patients; Sri Lanka.

MeSH terms

Aedes*
Animals
Antibodies, Viral
Dengue Virus*
Dengue* / diagnosis
Humans
Immunoglobulin G
Immunoglobulin M
Serologic Tests / methods
Sri Lanka / epidemiology
Zika Virus Infection* / diagnosis
Zika Virus Infection* / epidemiology
Zika Virus*

Substances

Antibodies, Viral
Immunoglobulin G
Immunoglobulin M