Aquatabs in a Cholera Response: Dosing, Logistics and What 52 Million Tablets Taught Us

In the 2024-2025 South Sudan cholera response, Specialized Logistics Solutions deployed 5,207 boxes of Aquatabs, more than 52 million individual tablets, with a combined treatment capacity exceeding one billion litres of water. That scale forces a discipline most dosing guides skip: the tablet only works if the dose, the contact time, and the supply chain all hold together at once. This piece sets out the dosing rules, the field corrections, and the logistics behind them.

How do you dose Aquatabs in a cholera response?

Use one Aquatabs 67mg tablet per 8 to 10 litres of clear water, then wait 30 minutes of contact time before drinking. If the water is cloudy, filter it through a clean cloth first, because suspended particles consume chlorine and shield pathogens. This dosing follows the CDC and Medentech instruction sheet for Aquatabs. The 30-minute wait is not optional padding; it is the time the free chlorine needs to inactivate the organisms in the water, and skipping it is one of the most common field errors during a fast-moving outbreak. SLS supplies the Aquatabs 67mg NaDCC tablets at the volumes a county-wide response demands.

The simple per-jerrycan rule follows directly. A standard 20-litre jerrycan needs two tablets; a 10-litre container needs one. Brief community distributors on the container in front of them, not on an abstract litre figure, because the people doing the dosing are counting jerrycans, not running arithmetic mid-queue.

What is the active ingredient, and why does it suit field use?

Aquatabs' active ingredient is sodium dichloroisocyanurate (NaDCC), a chlorine donor registered with the US Environmental Protection Agency and manufactured by Medentech Ltd of Wexford, Ireland, per Medentech. NaDCC suits emergency use for practical reasons: the tablets are stable in heat, light to ship, precise to dose, and they release chlorine in a controlled way once dissolved. For a response that has to move millions of doses through customs, a warehouse, and a last-mile run to a county like Renk, a stable, count-and-go tablet beats bulk liquid chlorine on almost every logistics axis. The trade-off is that NaDCC, like any chlorine donor, disinfects but does not remove the suspended solids that drive chlorine demand up, which is why turbid source water needs pre-treatment.

Why does the standard dose sometimes fail to hold a residual?

The single Aquatabs tablet per 8-10 litres delivers a correct initial dose, but in hot, overcrowded settings the residual can vanish before the water is drunk. In South Sudan refugee camps, between 40% and 58% of households drawing from chlorinated tapstands had no detectable residual chlorine in stored water, and researchers found standard doses could not ensure 0.2 mg/L of free residual chlorine 24 hours after distribution, recommending the initial target be raised toward 1.0 mg/L, per the Bulletin of the World Health Organization (2015). This is the gap between the manufacturer's instruction and outbreak reality. During an active cholera response in South Sudan, assume decay will be worse than the textbook, dose toward the upper end of the safe range, and verify a residual in stored household water rather than only at the tapstand.

The correction is operational, not theoretical. It means budgeting slightly more tablets per litre than the minimum, pairing tablets with covered storage containers so the treated water is not recontaminated, and testing free residual chlorine in homes during the response, not just signing off at the point of treatment.

How big was the cholera outbreak this dosing answered?

South Sudan's cholera outbreak, declared on 28 October 2024, reached nearly 100,000 suspected cases and more than 1,500 deaths across 55 counties, per WHO AFRO. Within a single window, from 1 January to 17 August 2025, the country reported 71,825 suspected cholera cases and 1,194 deaths, a case fatality ratio of 1.7%, per WHO Disease Outbreak News DON579. That CFR sits above the under-1% benchmark the WHO sets for cholera treatment centres, which is exactly why source-to-cup water treatment matters: every household that holds a residual is one less transmission route feeding the case count. The full SLS Aquatabs cholera response case study sets out the delivery record behind the response.

What did 52 million tablets teach us about the logistics?

The dosing rule is the easy part; keeping 52 million tablets flowing to the right county at the right time is the hard part. Three lessons stand out from the 2024-2025 response.

First, treatment capacity is not consumption, and saying so plainly protects credibility. The combined treatment capacity exceeding one billion litres is tablets multiplied by rated litres per tablet, a design figure, not a measurement of water people actually drank. Procurement officers respect a supplier who draws that line; it signals the same honesty you want applied to every other number in a tender.

Second, the stockout is the real enemy. A correct dose is worthless if the tablets are sitting in a port or a customs queue while a county's cases climb. The value of an in-country distributor with stock in Juba is that the dosing guidance above can actually be executed the week it is needed, not the month after. Prepositioning, customs clearance, and warehousing are part of the chlorination programme, not separate from it.

Third, dosing instructions have to survive translation to the last mile. A community health worker counting jerrycans at a tapstand needs "two tablets per jerrycan, wait while you walk home," not a contact-time table. The 52-million-tablet figure only converted into safe water because the per-container rule was simple enough to brief in a sentence. A broader range of treatment and storage supplies that support that last-mile discipline is available through SLS WASH products.

How do you test that the dose worked?

Test the free residual chlorine in the treated water, ideally in stored household water rather than only at the point of treatment. The target is at least 0.2 mg/L of free chlorine in stored water 24 hours after treatment, the household benchmark from the CDC Safe Water System. A DPD pool-tester reading taken in the home tells you whether the dose held through collection, transport, and storage, which is the only result that matters for breaking transmission. If the residual is consistently absent at 24 hours, raise the dose rather than blaming the tablet; the field evidence above shows the standard dose is often simply too low for the conditions.

Frequently asked questions

How many Aquatabs do I need for a 20-litre jerrycan?

Two 67mg tablets per 20-litre jerrycan of clear water, with a 30-minute contact time, per the CDC and Medentech instruction sheet.

How long should water sit after adding Aquatabs?

At least 30 minutes of contact time before drinking, so the free chlorine can inactivate pathogens, per the CDC and Medentech instruction sheet.

What is the active ingredient in Aquatabs?

Sodium dichloroisocyanurate (NaDCC), a US EPA-registered chlorine donor made by Medentech Ltd of Wexford, Ireland, per Medentech.

Can I rely on the standard Aquatabs dose during a cholera outbreak?

Treat it as a floor, not a guarantee; in South Sudan camps 40-58% of households had no detectable residual in stored water, and researchers recommended raising the initial target toward 1.0 mg/L, per the Bulletin of the WHO (2015).

How serious was the South Sudan cholera outbreak Aquatabs responded to?

It reached nearly 100,000 suspected cases and more than 1,500 deaths across 55 counties after being declared on 28 October 2024, per WHO AFRO.

Specialized Logistics Solutions is an in-country distributor based in Juba, an authorised distributor for Aquatabs (Medentech/Kersia), P&G Purifier of Water, and Oxfam tanks (Butyl Products), and a UNGM-registered vendor (No. 380716). The dosing and logistics here are drawn from a documented response in which SLS deployed more than 52 million Aquatabs tablets across South Sudan in 2024-2025, with treatment capacity exceeding one billion litres. Request a quotation from SLS to preposition Aquatabs before the next outbreak peak.