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Volume 32, Number 11—November 2026

Dispatch

Dirofilaria asiatica Infection and Asymptomatic Microfilaremia, Sri Lanka, 2025

Dilini Mataraarachchi, Iroshini Abeysekara, Harsha Narammalage, Thulangi Siriwardana, Nayana Gunathilaka, Murali Vallipuranathan, Prasanga Serasinghe, Lakmini Liyanage, Nilanka Perera, Guwani Liyanage, Shalindra Ranasinghe, and Nilmini ChandrasenaComments to Author 
Author affiliation: Anti Filariasis Campaign, Colombo, Sri Lanka (D. Mataraarachchi, I. Abeysekara, H. Narammalage, M. Vallipuranathan, P. Serasinghe, L. Liyanage); University of Kelaniya, Ragama, Sri Lanka (T. Siriwardana, N. Gunathilaka, N. Chandrasena); Colombo South Teaching Hospital, Colombo, Sri Lanka (N. Perera, G. Liyanage); University of Sri Jayewardenepura, Nugegoda, Sri Lanka (N. Perera, G. Liyanage, S. Ranasinghe)

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Table

Characteristics of Dirofilaria microfilariae detected in study of Dirofilaria asiatica infection and asymptomatic microfilaremia, compared with those of reference strains, Sri Lanka, 2025*

Morphology Microfilaria in this study D. repens microfilaria† D. asiatica microfilaria‡
Sheath Absent Absent Absent
Mean total body length, µm 349 369 +10 300.3
Mean width, µm
 8
 8.87+0.5
 5.7
Cephalic space
Mean length, µm 2.5 2.96 + 1.18 3.27
Location Round anterior end Round anterior end Not specified
No. nuclei
 2–3
 2 nuclei
 2–3 nuclei
Tail Tapering, curved, free of nuclei Tapering, curved, free of nuclei Tapering, curved, free of nuclei

*Specimens in this study were human blood smears stained with 10% Giemsa; we observed a mean of 10 microfilariae per specimen. Characteristics were obtained using Olympus microscope (original magnification ×1,000) and cell analysis software ScopeImage version 9.0 (https://www.bioimager.com). †Magnis et al. (5). ‡Colella et al. (2) Specimens were stained with 0.1% methylene blue.

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References
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Page created: September 08, 2026
Page updated: October 16, 2026
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