Developmental Cycle



The eggs of mosquitoes are brown or blackish and are laid singly or in rafts (1) on the water surface of diverse types of water collections; (2) on the undersides of floating vegetation, to which they are 'glued'; and (3) on wet mud, leaf litter, other damp substrates near the edge of water. In the latter case they usually hatch when flooded.

In nature, usually 4 to 5 ovipositions occur, each with 30-500 eggs. The site of oviposition is species-specifically chosen according to water chemistry and a circadian rhythm.

In the tropics, eggs hatch within 1-2 days, in cooler climates this process might take 1-2 weeks. Some mosquito eggs (e.g. Aedes and Ochlerotatus species) can withstand desiccation and may remain viable for months or years in a dry state.

Occurrence Maps

Each country has its specific occurrence of CVBDs depending on climate and endemic vectors. See the maps

Clinical Sessions

The following authentic case reports provide insights into selected CVBD cases

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Interesting Links

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CVBD Digest Articles

Findings from the CVBD symposia. More...