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Control of Diphtheria
1. Treatment of
– Cases and
– Carriers
– Management of the ‘Contacts’ and
3. At the community level
– Increasing coverage of immunization with diphtheria toxoid
Treatment of Cases and Carriers
Early detection
• An active search for cases and carriers should start immediately amongst family and school contacts
• Carriers can be detected ONLY by culture
• Swabs should be taken from both the nose and throat
• Examined by culture for diphtheria bacilli

The aim of post–exposure prophylaxis is to neutralize the inoculated virus BEFORE it can enter the nervous system
• Every instance of human exposure should be treated as a medical emergency
• The components of prophylactic treatment are:
1. Local treatment of wound
2. Antibiotics and anti-tetanus measures
3. Active immunization against rabies – if indicated
4. Passive immunization with rabies immunoglobulin – if indicated
5. Observe the animal for 10 days from the day of bite:

In 2000, 189 nations made a promise to free people from extreme poverty and multiple deprivations. This pledge became the eight Millennium Development Goals (MDGs) to be achieved by 2015.

Vaccines under UIP, India, 2016
Brief History of the Immunization Program in India
• May 1974:
– Expanded Programme on Immunization (EPI); Launched by WHO
– Included immunization against 6 Vaccine Preventable Diseases (VPD’s)
• Diphtheria,
• Pertussis,
• Tetanus,
• TB,
• Measles and
• Polio
– Later renamed as ‘Universal Child Immunization, 1990
• Jan 1978: EPI launched in India

• Nov 1985: EPI replaced in India by the ‘Universal Immunization Programme (UIP)

Methods available for purifying water on an individual or domestic scale are:
Boiling
Chemical disinfection
Filtration
Ultraviolet irradiation
Multi – stage reverse osmosis purification
These methods can be used singly or in combination
Boiling
It is an excellent method of purifying water but
For being effective:
The water must be brought to a ‘rolling boil’ for
10 – 20 minutes
Advantages:
It kills
All bacteria
Spores
Cysts and
Ova

OT Test enables Total, free and combined chlorine in water
The reagent is ‘analytical grade Orthotolidine’, dissolved in 10% solution of HCl
When this reagent is added to the water containing chlorine , it turns yellow
The intensity of yellow colour is proportional to the concentration of chlorine
This yellow colour is produced by both free and combined chlorine residuals
However, OT reacts with free chlorine instantaneously but reacts more slowly with combined chlorine
Add 0.1 ml of reagent to I ml of water

Steps in well disinfection:
1. Find out the volume of water present in the well using the given formula
liters
2.Find the amount of bleaching powder required for disinfection, Using ‘Horrock’s Apparatus’
3. Dissolve the required amount of bleaching powder in water
4. Delivery of the chlorine solution into the well
5. Allow a “Contact period” – one hour

Disinfection of Wells during an Emergency – The Double Pot Method
E.g. an outbreak of cholera
• During an emergency, it is desirable to ensure a constant dosage of chlorine to well water
• One method of doing this is the ‘Double pot method’
• The method is an improvement devised by the National Environmental Engineering Research Institute (NEERI), Nagpur, India
• There are two cylindrical pots
• One pot is placed inside the other
• Outer pot:
 Inside height is 30 cm
 Inside diameter is 25 cm

Horrock’s apparatus is used for estimating the dose of bleaching powder needed to disinfect 455 Liters of water
It is used mostly while disinfecting the water in a well

Contents of ‘Horrock’s Apparatus’
• 6 white cups, each of 200 ml capacity
• One black cup with a circular mark on the inside
• 2 metal spoons (each holds 2g of bleaching powder when filled up to the brim)
• 7 glass stirring rods
• One special pipette
• Two droppers
• Starch - iodide indicator solution
• Instruction folder

After calculating the chlorine demand from a sample of water, the calculated amount of chlorine is applied as
• Chlorine gas or
• Chloramine or
• Perchloron