Under-five diarrhoea cluster after a soak pit overflow

• Find and sort the cases first. A house-to-house search in both hamlets will almost certainly find more than the 11 reported. Screen every child under five for dehydration and danger signs: lethargy, sunken eyes, inability to drink, persistent vomiting, blood in stool, fast breathing. The two already referred need confirmation that they reached hospital.
• Treat: give low-osmolarity ORS and zinc to every case - zinc 10 mg daily for infants under 6 months and 20 mg daily for older children, for 14 days. Show the mother how to mix and give ORS at home rather than only handing over packets.
• Stop the source: advise immediate boiling or chlorination of drinking water from that handpump; take a sample for H2S vial testing and chlorination; ask the gram panchayat to close or relocate the soak pit and to repair the handpump platform and drainage.
• Break transmission: handwashing with soap at the four critical times, safe disposal of child faeces, covering food and water, and avoiding open defecation near the source.
• Report: inform the medical officer the same day and enter the outbreak in the IDSP reporting format; keep a line list from the first case.
• Plan follow-up: revisit in 48–72 hours to check that cases are resolving and that no new cases are appearing; a rising count means escalation for stool testing and wider water investigation.

Working:

• Water to treat = 5,000 litres.
• Dose required = 2.5 mg of available chlorine per litre.
• Total chlorine needed = 5,000 × 2.5 = 12,500 mg = 12.5 g of available chlorine.
• The powder is only 30% available chlorine, so powder needed = 12.5 ÷ 0.30 = about 41.7 g, i.e. roughly 42 g.

Weighing out 42 g on a laboratory balance is safer than guessing with a spoon; if only a spoon is available, weigh a known volume once and use that as a measure.

Application:

1. Make a smooth paste of the powder with a little water in a plastic bucket, breaking all lumps, then dilute to about 10 litres.
2. Add the slurry to the tanker while it is being filled, so that mixing occurs, or stir thoroughly afterwards with a clean long-handled pole.
3. Allow at least 30 minutes contact time before use.

Verification:

• Test free residual chlorine after 30 minutes; it should be about 0.2–0.5 mg/L.
• If residual is below 0.2 mg/L, add a further calculated dose and retest; if it is very high and the smell is strong, do not distribute the water for drinking until it falls.
• Record the weight used, the tanker number, the time of dosing and the residual reading. Also test the handpump water with the H2S vial to document contamination.

Line list - one row per case: name, age in months/years, sex, hamlet, date of onset, number of stools and vomiting, dehydration category, ORS and zinc given, referral and outcome, and the household water source. This turns a set of complaints into an epidemic curve you can defend to the block.

Other records: the H2S vial result and chlorine residual readings; the bleaching powder issued and balance in stock; the ORS and zinc issued against stock; the referral slips for the two severe cases; the date and time the medical officer was informed and the IDSP report was sent. Keep the ORS/zinc stock ledger current, because a stock-out in the middle of a cluster is a preventable failure.

Teaching messages, short and behavioural:

• Give ORS after every loose stool and continue feeding and breastfeeding; do not stop fluids.
• Zinc daily for 14 days even after the stools stop.
• Wash hands with soap before feeding and after toilet use; use a latrine and dispose of child faeces safely.
• Boil water or chlorinate it; store in a covered container with a ladle, not by dipping hands or cups.
• Cover food; wash vegetables and feeding utensils.
• Return at once if the child cannot drink, vomits everything, is drowsy, passes blood or urinates very little.

Deliver the messages at the household with a demonstration, not as a list, and check the mother can repeat the ORS mixing.