Overview of phlebotomine sand fly vectors of Leishmaniasis

Summary

This presentation provides an in-depth look at Phlebotomine sand flies, focusing on their classification, life cycle, external morphology, and behaviors. Sand flies, significant vectors of diseases like leishmaniasis, are small, hairy insects with distinct feeding and resting behaviors. The presentation covers their medical importance, including transmission of various forms of leishmaniasis, and their role in sandfly fever. Additionally, methods for collecting and monitoring sand flies, such as light traps and sticky papers, are explored. The presentation highlights the distribution, seasonal patterns, and surveillance techniques essential for studying these vectors.

Takeaways

• 😀 Phlebotomine sand flies are vectors of Leishmaniasis, a parasitic disease, and other diseases like sandfly fever.
• 😀 Phlebotomine sand flies belong to the order Diptera and the family Psychodidae. They are classified under the subfamily Phlebotominae.
• 😀 There are three genera of Phlebotomine sand flies: Phlebotomus (Old World), Lutzomyia (New World), and Sergentomyia (Old World, not significant vectors).
• 😀 Sand flies are small, with slender, hairy bodies and long legs. Their small size and hair make them difficult to notice when they bite.
• 😀 Female sand flies require blood to develop their eggs, while males and females feed on sugars from plants and fruits.
• 😀 Sand flies are nocturnal and bite humans and animals at night. Some species may bite during the day if disturbed in dark resting sites.
• 😀 The life cycle of the sand fly includes egg, larval, pupal, and adult stages, with optimal development occurring in humid environments.
• 😀 Sand flies are primarily exophagic (bite outdoors), but some species are endophagic (bite indoors).
• 😀 Phlebotomine sand flies have a weak, hopping flight and typically disperse only a few hundred meters but can travel up to 2 km over several nights.
• 😀 Sand flies rest in dark, humid sites during the day, such as inside houses, animal shelters, or caves.
• 😀 Various collection methods for sand fly surveillance include direct searching, aspirators, light traps, sticky traps, and CDC light traps with rotating platforms.

Q & A

What is the main focus of the presentation on phlebotomine sand flies?

The presentation focuses on the external morphology, life cycle, behavior, distribution, and surveillance methods of phlebotomine sand flies, particularly in relation to their role as vectors for leishmaniasis.

What diseases are transmitted by phlebotomine sand flies?

Phlebotomine sand flies are primarily vectors for leishmaniasis, which includes both cutaneous and visceral forms. They also transmit sand fly fever (Pappataci fever), caused by viral serotypes.

What is the classification of phlebotomine sand flies?

Phlebotomine sand flies belong to the order Diptera (flies), family Psychodidae, and subfamily Phlebotominae. Within this subfamily, there are three genera: Phlebotomus (Old World), Lutzomyia (New World), and Sergentomyia (mostly non-vectors).

What is the primary reason female sand flies bite humans?

Female sand flies bite humans to obtain blood, which is necessary for the development of their eggs, similar to mosquitoes.

What are the main characteristics of the external morphology of phlebotomine sand flies?

Phlebotomine sand flies are small with slender bodies covered in long hairs. They have large black eyes, long, spearlike antennae, and a humped thorax with lance-shaped wings. The legs are long and slender.

How can phlebotomine sand flies be differentiated from other similar insects?

Phlebotomine sand flies have lance-shaped, tapering wings and long legs. In contrast, drain flies have broader wings, and mosquitoes have a longer, piercing mouthpart.

What is the life cycle of phlebotomine sand flies?

The life cycle of phlebotomine sand flies includes the egg, larval stages, pupal stage, and adult. The eggs hatch in 1-2 weeks under optimal conditions, and the life cycle can take between 28 to 100 days depending on environmental factors like temperature and food availability.

What is the feeding behavior of phlebotomine sand flies?

Both male and female sand flies feed on sugar sources like plant juices, but only females bite to obtain blood for egg development. They are primarily nocturnal feeders, with some species also biting during the day if disturbed.

How do phlebotomine sand flies rest and disperse?

Phlebotomine sand flies rest in dark, humid sites during the day, such as inside houses or in animal shelters. They have weak flight and typically disperse only a few hundred meters, though some can travel up to 2 kilometers over several nights.

What methods are used to collect phlebotomine sand flies for surveillance?

Surveillance methods include direct searching using aspirators, light traps (like UV light traps), sticky traps, and collection bottle rotators. These methods help capture sand flies for further study, including morphological identification and blood meal analysis.