Day 12- Vector Control Unit

Today we began our day with briefing by the vector control unit, which is headed by Mr William. The briefing that was given to us was divided into 4 parts.

The 1st part : Case investigation, which was given by Encik Omar, one of the officers in the unit.

The 2nd part : Online registration of a case which was done by Mr. Burke

The 3rd part : Law & Acts of the government regarding the vector control cases (Dengue being the main), which was given by Mr. William

Lastly : Briefing on fogging given by Encik Pewira.

1. Case Investigation :

When a new case of dengue appears in district, the vector control department comes to know about it through phone calls, fax, e-notifications or by post. Informing the vector control unit is done by the general practitioners, hospital doctors, private hospitals and clinics. All of which have to inform the vector control unit within 24hours of the diagnosis.

If failed to do so, the specific clinic or hospital may be fined under the Act of Prevention & Control of Transmissible Disease 1988.

The order for case investigations :
1. New case reported by phone, e- notification, fax, or by post (more often than not by calls) by the hospital, GP or private clinics.

2. Health officer from the vector control unit goes to the specific hospital to investigate the case. Questions are asked regarding the disease.

3. Once information has been obtained in the hospital, the officer goes to the respective residence in search for any dengue mosquito breeding areas.

4. The officer then comes back to the office and the form is now re inspected, corrections are made, the form is completed and then passed over to the health inspector, Mr. William who then takes it up to Dr. Umi to be verified.

Note : In the form, each case of Dengue MUST have fever (the most important symptom) and 2 other associated symptoms.

Also, in the form, there is a section where the whereabouts of the patient 14days before the onset of the fever must be filled up. This is because the dengue incubation period is 14days and by obtaining this information, we would be able to trace back the source of infection.

Reason for investigation :

1. To know the status of the case - To find out if the patient hereby meets the criteria to be classified as a dengue case.

2. To know the cause of the infection - To know where the patient was when he got the infection.

3. To know the status of the spread of the infection - If there are 2 or more causes in the same area, it is known as a outbreak.

4. To take the most appropriate action to control the spread of dengue.

Aim of investigation :

Remove the virus from the area. - This is done by killing the adult and eggs

2. Online registration of a case.

When a new case appears, it has to be registered online. This is done by the District Health Centre to ensure they have all the information regarding the specific case in their system. The system was previously known as Veckpro but now has been changed to e dengue.

How it works?

When there is a new case in the district, it will be present in the e- notification. From here the vector control officer will log into the system, traces down the cases under vector control unit, for example dengue, and transfer it to e dengue. The complete details regarding the specific case is filled and appropriate actions are taken. The form is filled by the U29 officer and then transferred to the U32 officer and finally will be sent to the Health District Officer. Only then the case is considered complete.

3.Law & Acts by the Government.

What happens when a person is caught breeding larvae?
When a person is caught breeding larvae, a fine of Rm300 is charged upon him. Failing to pay the fine, he may be prosecuted.

To charge a person in court, permission to prosecute needs to be obtained, following which a fine, charge sheet and complaint are needed.

The 2 types of index that are used for dengue cases are the Aedes Index and the Breteau Index. The Aedes Index - Out of 100 houses, if one house has breeding, the index will read as 1%.

The Breateau Index - Based on the amount of larvae that is collected in containers. More than 5 containers per house labels it as dangerous.

4. Fogging.

Aim of fogging :

To kill mosquitoes that carry the virus.

There are 2 types of fogging that is usually done :

a) Thermal Fogging - the medication used for the fogging is heated at a high temperature of 1200 degrees Celsius with high pressure. At this temperature the particles are around the size of 5 - 50 microns. This allows it to float easily. Appropriate size is required because if the particle is too small, it may not work effectively and if it is too big, the particles will not be able to travel far enough to kill the mosquitoes.

b) Ultra low volume.

The concept of the fogging is to allow the gas to be in the air for a certain amount of time to ensure that the poison works on the mosquitoes properly.

Priorities for fogging are given to the areas with cases reported. Best time to do fogging is usually early in the morning at 8.30 and in the evenings around 5.30-8 pm (this is usually the peak time where mosquitoes are found to be more active). It also depends on the weather, rainy days fogging cannot be done. Officers who are handling the fogging must be dressed appropriately with the gloves, masks & proper shoes. The fogging medication should be sprayed in the house for 1-3 minutes for it to work adequately. Fogging is done from the back of the house heading towards the front and the fogging equipment is held at 45 degrees. Fogging is done for premises within of 200 meters radius from the reported case. Also during an outbreak, 4 rounds of fogging is done in the area with a minimum of 5 days and a maximum of 7 days between each fogging.

There have been no side effects of fogging upon humans that have been reported up to date.

Thank you.

Prepared by ,

-Nanthini-