Page 198 - policy and procedure infection control

Policies and Procedures on Infection Control

13.5 Dengue

13.5.1 Introduction
Dengue (DF) and dengue hemorrhagic fever (DHF) are caused by one of four closely
related virus serotypes of the genus Flavivirus, maintained in a cycle that involves humans
and the Aedes mosquito.

Aedes aegypti, a domestic, day-biting mosquito that prefers to feed on humans, is the
most common Aedes species. It is highly susceptible to dengue virus, is a daytime
feeder, has an almost imperceptible bite, and is capable of biting several people in a short
period for one blood meal.

The mosquito is well adapted to life in urban settings and typically breeds in clean, stagnant
water in containers that collect rainwater, such as tyres, tin cans, pots, and buckets.

13.5.2 Patient’s Isolation

Dengue patient need not be nursed in isolation room. However, an air-conditioned or a
natural-ventilated room is preferred.

If a natural-ventilated room is used, it is suggested to put mosquito nets to all the windows
in the room.

If both facilities are not available, then the patients can be nursed in the general ward.
Specific measures to avoid mosquito bites should be considered.

13.5.3 Prevention of vector transmission
1. Source elimination/reduction for Dengue fever

Source elimination or reduction is the method of choice for mosquito control when
the mosquito species targeted are concentrated in a small number of discrete habitats.
Among the suggested measures to make sure that there will be no breeding grounds
for mosquito in the area are:
• The larval habitats may be destroyed by filling depressions that collect water, by
draining swamps, or by ditching marshy areas to remove standing water.
• Container-breeding mosquitoes need to be identified and removed.
• Water in cans, cups, and rain barrels around hospitals should be covered.

• Chemical insecticides can be applied directly to the larval habitats.
Other methods, which are less disruptive to the environment, are usually preferred:
• Oil may be applied to the water surface, suffocating the larvae and pupae. Most
oil in use today are rapidly biodegraded.

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